)he pTcscnt invcntioB I'cl "jtcs to Bove] sc]ective 8AC& l Inhibitor% to
pharnlaccU'ilcRl conlposltions coIBpTlsnlg thc coinpounds, ro Blcrhods of Using 'ihc
conlpounds to treat phvslological dlsordcTs, Rnd to lntcTIncdlRtcs Rnd proccsscs Useful ln
5 thc synthesis of thc cornpoun«ls.
Thc plcscnt Blvcntion is in thc field of treatment of Alzhciiner s «llscRsc Rnd othcl
diseases Rnd disorders B1VolVing Rrnylolcl p (AbCra) pCptldC, R BCurotoxlC Rnd llighlv
aggregatory peptide segment of the amyklid precursor protein (APP). Alzheimer' s
discase is 8 devastating Bcurodcgcncrativc dlsordcr thRt Rffccts IBillioBs of pRtlcnts
l0 worldwide, ln view of thc curTcBI]v 8ppTovcd RgcBts GB thc mar'kct whlcl'1 afford only
transient, symptomatic benefits to the patient rather than halting, slowing, or reversing the
discase, rl'lcTc ls 8 siglliflcan'i UIBBct Bccd ln thc tTcatnlcnr of Alzhcimci s discase.
Alzhcnnci s dlscasc ls charactcilzcd bv thc gcncTatloB, aggregation, Rnd
«lcposltlon ol Abcta ln thc bTaln. Coinplctc 01' partial InhibitloB of p-sccrctasc (p-site
l 5 Rnlyhn«I precursor pi'otcln-cleaving cnzyirlc; DACE) hRs bccn sho'Avl to have 8 slgnlhcant
cAcct on pla«luc-related RB«l pla«luc-dependent pathologlcs in mouse Inodcl s Suggest mg
that even smaW reductions in Abeta peptide levels might result in a long-term siyuticant
TcductloB Bl plaqUc bUI'«lcB RB«l synaptic «lc flcits, thtis plovi«llBg signiflcRnt thcrapcutlc
benefits, .paltlculally in thc tTcatnicnt of Alzhcimcr s discase. ln R«klltion„ two holnologs
20 Of HACE hRvC bCCB IdentlllC«l which 8TC refer! Cd to Rs HACEl RBd BACE2, RBd It IS
believed that BACE1 ls thc Blost c4nically important to dcvclopnlcnt of Alzhciiner s
disease. BACEl is mainly expressed m the neurons while HAC.E2 has been shown to be
expressed pTH'BRTily in thc pcTiphcry (See D. Ochirich, BIoorg. !Ved. Chem. Lekr, , 24,
2033-2045 (20l4)). lB Rddit]GB„HAG,E2 may bc Important to plgrncBtation 8$ lt hRs been
25 1«lcBtificd Rs playlBg 8 Tolc in 'ihc pI'occsslBg of pignlcnr cell-spcciflc IriclaBocytc pl'otclB
30
(See L. Rochin„e/ a/. , Proc. ,'Cad. A«ad. S«i. USA„j3.O(26), l0658-l 0663 (20l 3)). BACE
inhibitors with central BcTvoUs systcIB (CNS) pcnctratlon, pRTtlcul8Tly lnhibl'toTs tl'lat RTc
selective toT H ACEl ovcT HACE2 RTc «IcslTc«!. to provide trcatIIIcnts toT AbctR peptidemediated
disorders, sUch Rs Alzhcinlci s «llscasc.
United States PRtcnt No. 8,158,620 dlscloscs fused Rminodihydrothiazinc
dcTlvativcs which possess BACEl inhibitory activity Rn«!. RTc fUTthcT disck)scd Rs useful
therapeutic agents for 8 neurodegenerative disease caused by Abeia peptide, such as
WO 2016/176118 PC T/US2016/028896
AlzhcHBcT s tvpc dcIBcn'tla. lB addition, United States Patent No. 8,338,407 discloses
certain fused aminodihydrothiazine derivatives having 8ACEl inhibitory effect useful in
treating certain neurodegenerative diseases, such as Alzheimer-type denientia.
Thc prcscBt Hlvcntion pTovldcs certain Bovcl conlpounds that alc HlhlhltoTs of
8ACE. Jn addition. the present invention provides certain novel compounds that are
sclcctivc Enhihltois of BACEI over BACE2. l uithcrmoic, thc prcscnt invcBtloB provides
ccltalB novel conlpolLBds which pcnctlRtc thc CNS. The pTcscnt lnvcBtion also pTovldcs
ccTtalB Bovcl coIBpouBds which hRvc tl'lc potcn'tlal foT Rn Unproved slclc-cAcct protllc, foT
examp]e, through selective inhibition of 8ACEl over 8ACE2.
Accor'dIIBgly, rhc prcscnr Blvcntloll pl'ovldcs 8 conlpouild of Fornlula l:
F
oT 8 phRTTBRccuticRHv acccptaMc salt thcrcol.
~«/H
S
O
N
NC
oi 8. pharlnaccuticaHV acccptablc salt thcrcol.
Thc pTcscnt lnvcn'tloB Rlso provldcs 8 BEcthod ot trcatUlg AlzhcHBcT s discase Ul 8
patlcBt, conlpTlslBg adiliiBistcring to 8 pRtlcnt IB Bccd of such trcRtB lent RB cffccIEvc
anlount of 8 coIBpolLBd ot Forlnulas l oT lR, or 8 phaTniaccutically acccptRMc salt thereof.
Thc pTcscnt lnvcntion fuTthcT provides 8 IBcthod of trcatUlg tl'lc pTogr'cssion of
20 IIEild cognitEvc UBpairrncnt to Alzhclmci s discRsc in 8 pRtlcnt, compTlslBg Rdminlstci Eng
to 8 patient Bl Bccd of such tTcatnlcni RB cffcc'tive alnount of 8 colrlpouBd ot &ornlulas l or
la„oT8 pharEBaccutlcaHy acccptaMc salt. thereof. Tllc pTcscnt lnvcBtlon 8lso pTovldcs R
Ulcthod ol Inhihiting BACE Ul 8 patient, coIBpTlsUlg adIBUHstciing 'to 8 patient In need of
WO 2016/176118 PC T/US2016/028896
sUch trc8tIBcBE Rri cffcctlvc RIBGUBt, ot 8 cornpourid of Forrnui8$ l or ia GT 8
pharEHaceutically acceptable salt thereof. i he present invention also provides a method
for Inhibiting BACJI'-Enedlatcd clcavRgc of Rinyloid prccuisol' pTotcEB, comprising
Rdnllnlstcrlng to R patlcnt En Bccd of sUch trcatIBcnt. Rn cffcctlvc Rmouiit ol 8. compound of
5 Formulas l or la, or a pharmaceuticaHy acceptable salt thereof. I he invention further
provides 8 IYEcthocl for iEEhibiting productloB of AbctR pcptl«lc, comprising R«lIHIBistcriBg
to 8 patient ln Bccd of such tTcatmcnt RB effective 8nlount of 8 colnpound of Formulas l oi'
la, or a pharmaceuticaily acceptable salt thereof.
FurthcTBIGI'c, th]s IBvcBtlon provides 8 conipound of FGTIBul8$ l GT la. GT 8.
l0 pharnlaccU'tlcRllv RcccptRMc salt ther'cof foE' Usc in thcl'Rpy, En particular foI' thc trcatIBcni
of Alzhcimcl s discase GT tor pTcvcntlng thc progrcsslon of mild cognitlvc lnlpaliirlcBt, to
Alzhc]mcr s dlscasc. Even turthcTB lore this IBvcBtlon provides thc Usc of 8 compoUB«l ot
FGI'IBUlRs i or ia, or R pharinaccutically RcccptRMc salt 'ther'cof, for 'thc mRBufacturc of R
irlcdlcairlcBt tor thc trcatIBcnt. of Alzhclincr s «IlscRsc.
Thc 1BvcBtion further pTovldcs 8 pharIBRccutlcal composltEGIE, comprjslng 8
compolmd of Formulas l or la, or a pharmaceuticaiiy acceptaMe salt thereof, with one or
morc pl'lar'B1RcclEtlcally RcccprRblc cRIYicI's, diluents, or cxclplcnts. Thc EnvcntiGB further
provides R process for pTcpRTlng 8 pharmaceutical composition„comprising RdinlxiBg 8
compound of Formui8s i or ia GT 8 pharmac ELtlcRilv Rcccpi8bi $Rlt thcTcot with GB GT
20 more pharlnaceuticaily acceptaMe carriers, diiuents, or excipients. This invention also
cnconlp8$scs Hovel intcTTBcdlRtcs Rnd pi'occsscs for thc synthesis of thc compouIKIs of
Formulas i and la.
Mild cognitive iEHpairment has been defined as a potential prodromal phase of
dementia associated with AlzhclIYEci" s «llscasc based Gn cliBlcal prcscniatlon Rnd GB
25 pTogi'cssloB ot p8ticBts cxhlblting Enlld cogriltivc Empalrincnt to Alzlicnnci s dcnlcntia
ovcT time, p4oriis, er «EL, ArcII. !VOLLEY)L, 58, 397-405 I'200l); Pctcrscn, ek ai, , .4PcP'I.
.VeLEroL, 56, 303-308 (l999)). The term "preventing the progression of mild cogmtive
EIBpRETmcnt to AizhclmcT's discase EEIcludcs restraining„slo'uvlng, stopping, oi Tcvcrsing
tl'lc pr'ogrcsslon of mild cogintivc impairment to Alzl'lclB'icT $ discase lil R pR'tlcnt. ,
As used herein, the terms "'treating'" or "to treat' includes restraining, slowing,
stoppmg, or reversing the progression Gr severity of an existing symptom or disorder.
As used hci'clB, thc tcrEB pRtlcnt. I'cfcTs to R human.
WO 2016/176118 PC T/US2016/028896
Thc tcI"In UEhib]t]GH of pTodUction of Abcta pcptidc' ls taken to mean dccTcas]ng
of ETE vlvo lcvcls of AbctR pcptldc ]H 8 pRticBt.
As Used hci'ciB, thc tcim cffcc'tive Rmonnt I'cfcr's to 'thc RmGEUIt GE' dose of
compoUnd of thc EnvcntloB, GE' R pharlnaccUticaHy Rcccptablc salt thereof which, Upon
smgle or mnltlple dose admmlstratlun to the patient, provides the desn ed effect m the
patlcn't Under diagnosis GE' trcatEBCBt.
An effective 81TloUnt Can bC IC8dlly deteTIBEIEed by the RttCndlng dlagnostEC]an„as
GBc sklHcd ln the Rrt, bv thc Usc ot krlown tcchnlqUcs Rnd by observing TcsUlts obtained
Under RB8iogoUs cncUBIstanccs. iB determining thc cffcctlvc 8]I]GUnt foT 8 pat]cnt, 8
io mnnbcr' of factors RI'c consldcrcd bv thc Rttcndnlg dlagnostlcERB, Enclnding„bnt Bot lnnltcd
to: thc spcclcs of patient; its slzc„Rgc„aBdgcncTal health; . thc specific discase GT disorder
]HVQivcd, thc degree Qf Qr ]Hvolgcmcnt Q] thc scvcritv Qf thc d]scasc Qr d]SQrde]
Tcsponsc of il'Ec individnal pRtlcnt; il'Ec pRTtlcnlRT coIYEpoUBd Rdlninistcrcd; thc mode of
RdIBEIEEstrat]on; thc bloava]labll]ty ch81'Rctcllstlcs of thc plcp81'RtioB Rdlrllmstci'cd; thc
dose Tcgimcrl sclcctcci; tl'lc Usc of CGBcomltan't mcdlcat]GH; RINl otl'lcT TclcvRBE
The componnds of the present inventioll are generally effective over 8 wide
dosage TRBgc. FGT cxalnplc„dosages pcT dRv BGTBMHy fRH w]thiB 'thc TRBgc of RboU't 0,0 l
to 8boUt, 20 Ing/kg Of body WClght. iB SOIBC ]BSERBCCS doSRgC lCvClS bClow thC loWCT lEBilt
20 of il'Ec Rtor'csald range DlRy bc IBGTc thRB Rdcqnatc„while En othci' cases stlH lRI'gcl' doses
may be empleyed with acceptable side CAects, and therefore the above dosage range ls
Hot EIEtcndcd to llnnt thc scope of thc irlvcBt]GH ]H 8Jlv way.
1 hc compoUHdk of thc pi'cscnt ]BvcBtloB Rre prctc] Rblv foTIBUla ted 84
pharnlaccU'tlcRl conlposltlons Rdmimstclcd by Rny I'GUtc which makes thc colnponnd
25 b]oavallablc„]IEclUdlng GTal RBd transdcrmal TGUtcs. Most preferably, sUch colnposltions
8TC toT Oral RdIH1BEStrat]OH. SUch pharnMCCUt]cal COIBpoSltionS RIEd pTOCCSSCS foT
preparing same are weH known m the art. (See, e.g., Lexington: The Science and
PI'Rctlcc ot PharIBRcy„ IL.V. AHcn„Edltoi', 22 EdltEGIE., PharmaccUt]cal Press, 2012).
Thc compoUHds of FormUlRs i RBd iR GT phRIIBRccUUCRHy Rcccptablc salts thereof
30 are parbcniarly Usefni in the treatment methods of the invention, bnt certain gronps,
snbstitnents„and confignrations are preferred. The foHowing paragraphs describe snch
prclclrcd groUps„sUbstltUcnts, RINl conflgUEatlons. it wEH bc UBdcrstood. thRt these
WO 2016/176118 PC T/US2016/028896
pTcfcTcnccs RTc apphcablc both 'to 'thc trcatB'lcBt, Blcthods RBd to tIlc Bcw conlpouBds of
thc invcntloB.
Thus, thc colnpound of Foinlula I wherein rI'lc fused bier'c11c Tiilg ls ni thc cis
configuration, oi pharBlaccuticai]p acccptaMc salt thereof, ls preferred. IFor cxanlplc, onc
of ordrnarv sklH m the art wlH appreciate that the compound of Formula Ia ls m the cis
relative configuration for the centers labeled 4a and 7R as shown in Schenle A below. In
addition„ thc preferred Tc]atlvc conflgui'ation for thc three chlral ccntcTs of Foilnula Ia ls
shown IB ScheInc A whcTcril thc dlfiuoiocthp"i substituent at position 5 Es IB 'thc cis
configuration rejatlve to the hvdrogen at position 4a and the substituted phenvi substituent
I0 at positloB 7R:
SChelTle A
Further conlpounds of thc pTcscnt. lnvcBtloB lnchEdc:
WO 2016/176118 PC T/US2016/028896
F
F
' ". 2
Q
Althongh 'thc pl'cscn't IBvcntlon contcnlplatcs RH individnal cnantioB1crs and
dlasteTOIBCTS, RS WCH RS IBIXtUTCS Of 'thC CBarltlolTICTS Of Said colnpoUBdS, TtlclUdlng
TRCCBIRICS, thC ConlpoUBdS AVith thC abSolntC Conflgnrat! OB RS SCt forth beloW RTC
palticniarly preferred:
N-[3-[(4aS,5S„7aS)-2-amino-5-(l, I-di flnoroethyl)-4, 48,5„7-tetrahydrofUTO[3, 4-
d] [l„3jthlazIB-78-yl ]-4-IIUoro-phenyl]-3-cyRno-pyTI drtlc-2-carbox amide, RBd the
pharmacenticaliy acceptable salts thereof.
hl add ltlon„N- I 3-[(48S,5 S,78S)-2-amino-5-(l „ l -dlflUolocthyi)-4, 48„5, 7-
tctrahydrotnro[3, 4-dj [l,3]thlazin-78-yl]-4-fI UoTo-phcny lj-5-cy ano-py Tldlnc-2-
carbox NBIde;
N-[3-[(4aS,5S,78S)-2-amino-5-(l, l-di flnoroethyl)-4, 48,5,7-tetrahydrofnro [3,4-
d] [ l„3jthlazln-78-ylj-4-flUom-phenyl j-5-cyano-pyrldlne-2-carboxalnlde
] 3 IncthancncsUl fonatc„'
N-[3-[(4aS,5S,:RS)-2-amino-5-(l, l-dÃUoroethyl)-4, 48,5,7-tetrahydrofUTO [3,4-
dj [l,3]thlazln-78-yl ]-4-flnoro-phenyl] -0-cyano-pyrldlnc-2-carboxamldc 4-
methyibenzenesUifonate; and
N-[3-[(48S,5S,78S)-2-amino-5-(l, l-dIII Uorocthyl)-4, 48,5,7-tctTRhydrofUTo [3.4-
20 d] [1„3]thlazIB-78-plj-4-fino ro-phcnylj-5-cyano-pyrldlnc-2-carboxamldc 4-
methylbenzenesUlfonate hemihydrate„are especially preferred.
N-[3-[(48S,5S,78S)-2-amino-5-( l, l -di tkUorocthyl)-4, 48,5,7-tctrahydrofUTo [3,4-
d] [l.3jthIRZIB-78-ylj-4-fIUOTO-phenyl]-&-cyano-pyr&dhne-2-carboxamlde 4-
BlCthyibCBZCBCSUlfonatC; and
WO 2016/176118 PC T/US2016/028896
N-[3-[(48S,5S,78S)-2-8TMB0-5-(],l-dII] uorocthy])-4, 48,5,7-tctTRhydrofuro [3.4-
dj [i 8jthlazin-78-y] j-4-f]uoro-phcnv]j-0-cvano-pvrldinc-2-carboxamldc 4-
mcthy]bcnzcncsu]fonatc hcnuhydratc RTc B1ost cspcclRHy pr'cfcIYc«l.
One of ordinary skiH in the art &viH appreciate that compounds of the invention
can exist IB t8lltonlcl ic foTlns, Rs dcplctcd bc]ow in Scheme H. W]'lcn Rny Tcfcl cncc IB
this appHcation to one of the specific tautolners of the compounds of the invention is
glvcB, lt is uB«icTstood to cncolrlpass both tautolrlcrlc foTrns Rnd 8H BllxtuTcs thci'cof.
Scheme 8
~NQ I - F
A«ldltroBRHv, ccl t81B lntclnlcdlatcs dcsciibc«i IB thc ]oHo"vvlng pTcpaTRtions Blay
coBtain onc oT BloTc nitrogen protect! Bg groups. li ls undci'stood that pTotccting groups
may be varied as appreciated by one of skiH in the art dependmg on the particular reaction
condltIons Rncl. thc particu]ar trans]oIDlatlons to bc performed. Tile pTotcctlon Rnd
cicpr'otcctioB conditions RTc AH knosvn to thc skiHcci artisan 8nci 8Tc dcscr'ibcd Ul the
l5 ]itcratN c (Scc for cxanlp]c GPeeIie 5 PI ofectlve GI:oops iil OI'gQIllc 5$71IAe$1$, Fourth
Edition, by Peter G.M. Wuts and Theodora W. Greene, John Wiley and Sons, Mc. 2007).
]Bdlvldua] isoIBcTs, cnRBtiomcTs, 8nd d18stcrcoincrs ITLRv bc scpRTatcd ol Tcsolvc«l
by oBc of ordULary skiH ln thc Rrt 8t RBy convcTllcBt polBL Ul t]'lc synthesis of colripouB«is
of Ihc invention, by Blcthods such Rs sclcctlvc crystRHIzation tcchm(jucs ol' chlTR]
20 chTonlatoglRphy (Scc ]or cxamp]c, J. Jac«lucs, 8/Q/. „~El'IQIirlomel'5, RQceMQ/es, Quid
Resolutions", John WHey and Sons, inc. , l98 l, and E,L, Elle] and S.H, WI]en, "
5/eI'eocAeIIIIsIIp ofOE gQILic CoIIIpouIlds, %Hey-lBtcrsclcncc, ] 994).
A pharnlaceuticaHy acceptable salt of the conlpounds of the invention, such as a
hydrochloride salt, can be forined, for example, by reaction of an appropriate tree base of
25 8 con%pound of thc invcBtion, Rn RppTopliatc phalmaccuticRHy RcccptRbic 8cid suc]'1 Rs
irydrochioric acid in a suitab]e solvent such as diethyl ether under standard conditions
LvcH kno'Avl in thc RTt. AddltionRHy, thc forlnatlon ot such sR]ts CRB occur slmu]tancous]y
WO 2016/176118 PC T/US2016/028896
UpoB dcprotcctrorr of 8 rutrogcn pr'otcctirig gT0Up. T]'lc formation of such $R]ts is wc]]
kBoxvtl Rnd 8ppTcclRtcd In thc art. Scc, foT cxRIBp]c, Gou]d, P.L., Sa]t sc]cctloB foT bRslc
drugs, IEIteE7'EQtroEEQl JolEE'EEQ] OfPlitvtEEQCE". @tres, 33: 201-217 (]986);Bas'tin, R.3., et Ql.
'Salt Selection and Optimization Procedures for Pharnlaceutlcal Net Chemical Entitles, "
Ot gQE'Elc PE'ocess ReseQE"CA Qtld i)evelo]EErrerrt, 4: 427-435 (2000): Rnd BcTgc, S.M., et Ql. ,
Pharmaccutrca] Salts, JQEEEEEQlof P/IQE'EIIQceEEticQl Scietrces, 66: 1-19,(19/7).
CCltalB abbr CVlatlonS 81C dCfinCd RS fo]]OV;S: 'APP" TCfCTS to RIBC]01d prCCUTSOI.
protcirr; . BSA TcfcTs to Bovine ScTurrl A]bumin; CDi TcfcTs to ],1-
carbony]dEImIda70]c CDNA Tctcl s to corrlp]cnlcnt8ry dcoxvr'lbonUc]clc Rcld DAS 1
10 rcfcTs io diethyl]anrinosu]fur trifiuoridc; "DCC"Icfcrs to ],3-dicyc]ohcxy]carbodiimidc;
'D1C" IcfcTs to ],3-drlsopropy]carbodlrmldc„'DllPEA" TcfcTs to N„Ndnsopropy]
cthy]RBBBc; DMAP Tcfcr's to 4-dIEBc thy]RIIBnopyrEdrnc; DMSO TcfcTs to
dimethyl sulfoxide; "EBSS"'refers to Earle's Balances Salt Solution; "EDCF"refers to 1-
(3-dimcthy]aminopropy])-3-cthy]carbodllrnrdc hydroch]0TIdc; EL1SA I'cfcTs to cnzvBlchnkcd
Immunosorbcrrt assay, " F12 TcfcTS 10 HRrrl s F1 medium' FBS Tcfcr'8 to Fcta]
Bovine Serum; "Fc"refers to fragment cq,"sta]]izab]e; "'FLUOLEAD™refers to 4-tertbuiy]-
2, 6-dinrcthy]phcny]su]fur trif]uoridc; FRET ' I'cfcrs to f]uorcsccncc TcsonaBcc
cncTgy transfcT; ~HATU Tcfcrs to (dirncthy]RIIBrro)-N, N-dirrrcthy](3If-
I ],2,3jtriazo]0 I 4,5-&jpyridin-3-y]oxy)rncthanirrBrriunI hcxaf]uorophosphatc„' HBT1
20 refers to (1H-benzotriazol-l-y]oxy)(dimethy]amino)-N, N-dimethy]methaniminium
hexafiuorophosphate„'HEK" refers to human embryonic ]adney; "F]F-pyrrdrne"' refers to
hVdTogCB f]UOTldC pyrrdrne OT O]a]'1 S TCagCBt, OT po]y(pyridIBC f]uorrde)„' HOBT TCfCTS
to ]-hvdroxy]bcn70trr870]c hvdratc K.50 Tcfcl s to thc conccntrat!on of Rn Rocnt that
produces 50',4 of the maximal inhibitory resporlse possible for that agent; "HRP" refers to
25 horseradish pcroxrdasc; . "IIgGI" TcfcTs to Imrnunog]obu]ln-]Ikc doinarn Fc-gamlna
I'cccptoT; MBP' TcfcTs 'to ma]tosc bindlrlg protcln; MEM ' I'ctcTs to Minimum EsscntiR]
Mediunl; "PBS"'refers to pllosphate buffered sa]ine: "PDAPP'" refers to platelet derived
Rrny]ord plccuTsol pTotclB; PyBOP Tcfcls to (bcnzotll8zol-1-v]-
oxytrlpyrro]rdrrrophosphonrum hcxafiuorophosphatc); PvBTOP TcfcTs to br'omo('trl-
30 pyrro]idiny])phosphoniurrrhexaf]uorophosphate; 'RFU" refers to re]ative f]uorescence
unit, "RT-PCR"' refers to reverse transcription polymerase cham reaction; "SDS-PAGE"'
Tcfcls to sodlunl dodccy] sulfate po]vaclyl8BIK1c gcl clccti'ophol'csls: , THIF ' lcfcls to
WO 2016/176118 PC T/US2016/028896
tctrahydroturan„' TA'li3 Tcfcrs to tctramcthyibcnzidlnc„' TA'lEM TcfcTs to
tran snlcnlbTanc pl otclB; Tl ls 1 cfcl's to tris(hydroxyBIcthyl)RIHIBGBIcthanc; trltyp I'cfcTs
ro 8 group of the formula (Ph);C-: Xi@3 TcfcI's ro X-Ray Powder Diff1'RctloB;
'XtallFiuor-EFr 3GT HAST dIfiuorosulflnluln salt."Tcfcls to
(dlethyiaIHIBO)dltluorosul fonlum tetrafluoroborate or A,N-diethyl-5, 5-
difluorosuifIHminiunl tetrafluoroborate; and "XtalFluor-M or morpho-DAST
dlfluorosUlfinluln sRlt lcfcl's to dlflUGIG(lrloTphollno)suitonluIB tctrafiuoroboratc or
dlfjuoro-4-morphohnvlsulfoIHUIB tctTaflUGToboTatc.
Jt is lmderstood by one of ordinary skiH in the art that the terms '"tosylate",
io "tolUcncsulfoBlc acid'", "p-toiucncsulfonic acid"', Rnd "4-mcihylbcnzcnc sulfGBlc acid'"
refer to the compound of the foHowing structure:
Thc colnpounds of thc pI'cscBt lnvcnilon, or salts thcl'cof, may bc pI'cpRrcd by 8
var'lc'ty of pToccduTcs known to GBc of ordinary skill IH thc RTf., some of wl'Hch RTc
illustrated in the schemes, preparations, and examples below. One of ordinary skill in the
art recognizes that the specific synthetic steps for each Gf the routes described may be
combined In dlffcl'cni. wRys, ol' IB conjunctloB with steps fTGIB dIAcrcnt schclrlcs„ to
pTcpar'c compounds ot thc lnvcntioB, or salts thereof, Thc products of each step ln thc
schemes below can be recovered by conventional methods well known in the art,
20 including extraction, cvapolatlon, precipitation, chrolnatoglaphy, filtration, trltU1RtloB,
Rnd crystaHization, ln tl'lc schemes below, RH substitucnts UBlcss othcrwlsc indicated, RI'c
as previously defined. The reagents Rnd startmg materials are readily available to one of
ordinary skill IB rhc Rrt. Without Hmitnlg rhc scope of rhc invention„ thc following
schemes„preparations„and examples are provided to tuliher IHustrate the Invention.
WO 2016/176118 PC T/US2016/028896
E Step A
PG'
Step B pc-'"~X&
PG- y.
"
PG-0
OH
Pf
0-
PG
0 0~
PG- c
P~~
10
NH2
QH 0
0
N N
X
Step K
N
H0~&
Q
Ho
Q
Step J 0
step L
0
H
0 S
H
N "N
Ql
F
F- ~ H
Rr
F
F
hx Scheme 1, step A, tTimethyISUlfoniUm iodide is heated with RTt QTgmic base
5 sUch as n-be'IIlti'BUm at R 'tcn1pcTatU1'c of aboUt -50 C ln 8 solvent sUcI1 as THF. A
pTotcctcd oxpFmcthp'] oxllallc, pl'otcctcd 'uvlth 8 sUltal3]c pTotcctmg gTQUp, sUch Rs 8 tTltfI
WO 2016/176118 PC T/US2016/028896
group, 1$ t]'lcn added to thc basic sohitioB at -]0 C RJld 8]]owed to stn' for' about houTs to
glvc thc pTotcctc«!. product ot SchcTBc l Step A. PG ls 8 protcctlBg group «!eve]oped
for the amino group or oxygen group such as carbamates, amides, or ethers. Such
pTotccting gToups RE'c wc]] known and appTcclRtcd lB thc RE't. Thc pTotcctc«l pToduct of
Step 4 ls Teactc«l wrth an EL-ha]ocstcr such 8$ teF/-butoxv bT0BIoacctatc Using tetra-8-
butylammonium sulfate or other quaternary ammonium salt phase transfer catalysts in a
so]vent su.ch 8$ tohLcnc and an aqueous Inorganic base such R.s sodlunl ]iy«]ToxKI.c at about,
T00B'1 tcnlpcraturc to glvc t]'lc coIBpoUIld of Scheme ]„Step8, Such 8]kylatioBs RTc wc]l
known in the art. Alternative]y a base such as 60".o sodiunl hydride in oi] with so]vents
]0 sUch 8$ 5„N-diB1cthy]formairBdc or THF RIK] 8 tcnlpcr'atuTc TRBgc of 0 to ]00 'C caB bc
USCd to giVC thC protected pl'Oduet Of StCp H. ThC /eP/-butoxy CalboBV] RCCtatC ES
coBvcrtcd to Rn oximc ovcT 8 2-step pToccdurc. A TcduciBg Rgcnt such 8s
isobutylaluminum hydride in hexanes is added dropwise at a temperature of about -70 'C
fo]]owed bv thc dropwlsc addition of RB aqueous RCK] such as hy«lioc]i]oilc 8cld at 8
tcIBpcraturc of abolLt -60 OC. Thc work-Up 1$ accoIBplis]'lcd with 8B or'gRBlc extraction to
give the intermediate material. This materia] is dissolved in an organic solvent such as
dichloromethane and treated with sodium acetate fo]]owed by hydroxy]REBine
hydroCMOTEde to givC thC OxHBC pTO«]UC't Of StCp C. ThC Oxn'BC pTO«]UCt. Of SChCIBC i, StCp
C Can bC ConvCTtCd to thC bECyC]EC 4,5-dlhydroisoxazo]e pTO«]UCt. Of StCp D 1B8 3+2
20 cyclization by several methods such as using an aqueous solution of sodium hypochlorite
01' Rn altcr118tlvc oxidant such as N-ch]orosucclnimidc and EB 8, solvent sUch Rs k'el /-buty]
Glcthyl ether, tolucnc, dichloTomcthRnc„oT xy]cnc at 8 tcmpcratuTc of about ]0-]5 C 0T
with heating. The 2-f]uoro, 5-bromo pheny] group can be added to the dihydroisoxazole
by generating the organometa]]ic reagent. The organometalhc reagent can be generated
25 fTom 4-bromo-l-f]uoro-2-Eodo-benzene Using halogen-IBctal cxchRngc with TcRgcnts such
8s B-buty]]ithEUIB or Esopropy]magnesium eh]or'idc lithluIB chloTidc comp]cx Rnd dropwisc
addltE0B at 8 tcnlpci'aturc range of about -78 ~C to ]5 C Bl 8 $0]vcBt such as EH''. A
Lewis acid such as boron tTlfiuoTK]c dicthvl cthcTatc ls then added to glvc thc pT0«Iuct of
Scheme l St"p F The Iesu]ung bicyc]lc tetrahydrolsoxazo]e can be tr"ated v;1th zmc lri
30 RCCtlC RCid to form thC Ting OpCBCd product Of SChCIBC i, StCp F. AH 8]ternate IBCtho«] to
open the isoxazole ring uses Raney Nicke] in a polar solvent such as ethanol under
pTcssuTc with hydrogenation conditions. Thc pToduct. of Step F CRB then bc lcactcd with
WO 2016/176118 PC T/US2016/028896
benzoyl lsotl'Hocyanatc ]H 8 solvcBt, such Rs d]chloromcthanc GT THF at R tcInpcTatuTc of
about 5 'C to room temperature to give the thiourea compo]]nd of Step G. The thiaz]ne
TiBg can bc for]ncd Using trlfluoronlcrhancsulfGB]c anhydride and RB or'gaB]c base such as
pyr]d]nc lB 8 solvcBt, such as d]chloromcthanc at 8 tc]npcraturc ol about -20 C to glvc thc
5 product of Step H. I hc hydroxymcthyl protecting gToup such as 8 t] ityl group can bc
removed in Scheme l, S'tcp l. Us]Bg methods well known in thc art such as folmic acid Rt
room temperature to g]ve the compound ol Step II. The hydroxy methyl can be ox]d]zed
to tl'lc cRTboxyl]c acid Us]ng ox]d]z]ng RgcBts such as 2-lodoxybcnzo]c Rc]d (IBXJ R't TGGIB
temperature ]H 8 solvcBt such as DMSO GT portlonwlsc add]t]GH of
l 0 (diacctoxyiodo)benzene 1B 8 solvent sUch Rs acctonitlilc wlil'1 stirring ar 8 tcnlpcratUI'c of
about 5 'C to give the compound of Scheme l, Step J. The %C]nreb am]de ls prepared m
Scheme l, Step K from the acid product of Step J with the addition of N,OdlnlcthvihydI'oxylRBUnc
hydrochlor]dc, an GI'gaB]c base, such as tr]cthylam]nc„and 8
coupl]rig lcagcnt sucll as HATU. Thc InixtuTc ls stirred at, 100]rl tcB]pcTatuTc to glvc thc
pTodUct of Step K, OthcT coUpl]Bg RgcBts 'thRt, coukd bc Used include Col, carbod]]nudcs
sUch Rs DCC, DJC, 0] EDCl GT othe]' Uron]u]II or phosphoBrum sRlts of Bon-Bucicoph]lrc
RBlons, such as lrBTU, PyBOP, and Pp BTOP. Thc Wcinrcb Rmidc ls then converted to
thc kc'tone Us]ng 8H GI'gRBGB'lctall]c TcagcBt, such Rs 8 GT]gn8Tcl I'cagcnt GT 8H
organoi]th]un] reagent Tll Step L ln R solvent. such as THF. Spec]ficanv,
20 ]ncthylnlagncsiu]n bl'onudc as 8 solU'tlon ln solvcB'ts such as cthcr or 2-
methyltetrahydrofuran can be added to the %C]nreb am]de at a temperature ol about -78
C 'to -40 C 'to give thc kctonc ot Step L, in Schcmc l, Step M, tl'lc IBc'thyl kctonc gI'oup
Qf thc CQ]npQI]nd Qf Step L ]s converted tQ 8 d]fluoloethyi grQup Us]ng
difluolo(nlorphoiino)sulfoBlum tcirafluoroboI'aic m R solvent such as dichioro]nethanc Rt
25 about 0 'C followed by the dropwlse addlt]on ot tr]ethylamlne tr]hydrofiuor]de and
stirrirlg at 0 'C to room temperature to give the compound of Scheme l, Step M,
Alternatively, Other fluorinating agents that may be used which are well known in the art
are DCOXO-IFluor„BAST, XtalFluor-Etlf or XtalFluor-lVMi with at& add]tive such as
tr]cthylalnlnc tr](hydrogen fluor]dc) GT FLl1OLFAD™using 8H addi tlvc sUch Rs HF-
30 pyrldme The 5-bromo of the phenvl ls converted to the amme usmg (lR 2R)-N 5'-
dimethyl-l„2-cyclohexanediamine in a solvent such as ethanol a]id adding sodium azide
followed by sodium ascorbate and cupric sulfate. The reaction is heated to about 80 'C
WO 2016/176118 PC T/US2016/028896
for scvcTR] hours and then worked up wl'th RB cxtTactioB using 8 so]vcrlt. such Rs cthy]
Rcctatc. Fhc IBIcTIBcdiatc ls then TcdUccd under hydrogcnat! on condltloBs uslBg
pajjadIUBI on calbon such Rs ]0/0 paljadluIB ln. solvents such as ethanol Rnd jHi' at 8
pTcssuTc of about 50 psl oj hydrogen to glvc thc RBlhnc product ot SchcBlc ], Step N.
Br
G
Step C
PG
Q
Ste E
Br
PG
Q
~8te D
N
H
B. PG-Q
Br
Q
GIH
N
Alternatively in Scheme la, the protected product of Scheme l, Step A, can be
]0 treated with 4-(2-chjoroacctyj)IBorphojlno Rnd 8 base such Rs tctlabutyl RIBBlonrum
hydrogen su] fate In 8 solvcB't such Rs to]Ucnc Rt 8 tcmpcr'8tuTc of about 5 C to glvc thc
product of Schcrnc lR, Step A. Yhc Blorpho]lno gToUp cRB thcB scTvc Rs 8 ]caving group
in Scheme la, Step B. For example, tile product of Schenle la, Step A can be treated
wIth thc RppTopT18tc Grlgnard I'cRgcnt which CRB bc pTcpRTcd in sl'tu &om isopr'opv]
magnesrum ch]orlde ]lthlum ch]orlde comp]ex and 4-bronto- j-fjuoro-2-Iodobenzene or lf
thc RppToprlatc Grlgnald Tcagcnt ls Rvallablc, tj'lc Tcagcnt CRB bc added dlr'ectly to thc
product of Scheme la, Step A at a temperature of about 5 "C to give the product of
Scheme ]8, Step ]3, Thc caTboBvj Rcc'tRtc cRB bc coBvcrtcd to Rn oxH'Bc with
hydroxv]amlnc hydl'ochlol'ldc Rnd sodlurn RcctRtc with hcRtlBg to about 30 C Io glvc thc
20 pl'odUC't of SchcIBc la, Step C. Tile oxnrlc product of Scjlcmc lR, Step C caB tllcn bc
WO 2016/176118 PC T/US2016/028896
converted to 'thc product of SchclBc iR, Step 0 Cthe same pr'odUcf. Rs SchclTlc ie Step E)
Using hydroquinonc 1B 8. soivcBt sUch as to]Ucnc RBd hcRtlng to Tcf]ux. (he amlBc pTodUct
of Scheme ]ac Step 0 can be acyiated v;ith acetyi chiolide using an organic base such as
DMAP and pyrldme m a so]vent such as dlchioromethane at a temperature of about 0-5
'C to give the product of Scheme ]a, Step E. The product of Scheme ia, Step E can then
bc convcrtcci to thc product of Sci'lcnlc 2, Step A as discussed bc]0&v.
HG
H
0
Ho~~
H
p~p
Step 8
0
Step C
~F
p~p
~h Btep B
0
p~p
~0
0
H
Btep D
Step F
F
I-f
Step 6
OH
NH,,
Btep H s 0
iB RB aitclnatc loiiltce Rs dcscllbcd 1B Scheme 2e thc lsoxRzoic nltlogcrl of thc
compound of Scheme i Step i' fs protected wfth an acetvi group and the protectln~
groUp of rhc hydroxy nlcrhy] ls 1'cnlovcd 1B 8 hvo-step procedure. )For' cxanlpic, thc
WO 2016/176118 PC T/US2016/028896
tctrahydrolsoxazoic is treated vv'ith Rn GI'g8Blc base such Rs DMAP Rnd pyrldlnc ln 8
solvent such as dichkwomethane and acetyl chloride is added. The temperature is
malntalncd bciovi about l0 'C and then allowed to stlI' Rt about Toonl tcB1pcraturc l hc
Tcactlon ls dliutcd xvlth xvatcr Rnd extracted with 8, solvent sUch Rs dlchiol'Onlcthanc. Thc
5 organic extracts are vvashed vvith an aqueous acid such as i N hydrochloric acid and the
aqueous cxtl'acted again lvlth 8 solvent sUch Rs dlchioroB1cthanc fGHMvcd by Rn aqueous
xvash. Thc organic solvent ls partially lclnovcd RINl Rn RCKl such 8$ lorlnlc RCKl ls added
to clcprotcct thc hvdroxy Blcthyi. Thc Inlxturc CRB bc stirTcd Rt, TGGBI temperature GT
heated to a temperature of about 40 '"C Until deprotection of the hydroxy is complete to
l0 glvc thc COIBpoUIKl of Scheme 2, Step A. Thc hycIToxv Irlcthyi product Of Schcnlc 2„Step
A cRB bc oxKllzcd to thc caTboxvilc RCKl pToduct of Scheme 2, Step 8 ln 8 BIRBBcr
analogous to the procedure described in Scheme i, Step 3, and the Weinreb amide can be
further prepared in a manner analogous to the procedure described in Scheme l, Step K
usIng R coupilBg agent such as Col in 8 portlonv;Isc Rddltlon Kvlth 8 solvent such Rs
dlchiororncthanc& cooling to ' 0 C Rnd surrlng for Rbou't i hour 8nd adding N 0
dlmethyihvdroxyiamme hydrochloride portlonwlse Further addltKms ofCm Rnd N 0-
dimcthyihydroxyiaminc cRB bc added until complete Tcactlon ls Obscrvcd io glvc thc
'lVcinrcb amide pTodUct of Scheme 2, Step C. Thc kctonc of SchcIBc 2, Step D cRB bc
formed from 'thc %c]nrcb amide rtl 8 IBRTlncT Rnaiogous to thc procedure described In
20 Scheme i, Step L. The ketone of Step D can be converted to a difiuoroethyi group in 8
BIRBBcr RB8iogous to thc ploccdulc described ln SchcIBc l, Step M to glvc thc product of
Schclnc 2, Step E. Thc 8cctvi tctrahydrolsoxazoic caB dcpTG'tcctcd Under Rcldlc
conditions weil knovm in the art such as using hydrocMoric acid and heating to about l00
'C to glVC thC prodUct Of SchelrlC 2„StCpF. The bicycilc tCtrRhydTOISoxazoiC can be
25 treated xvlth zlBc ln Rcctlc acid io forIB ihc I'lng opcncd product ol Schclnc 2„StepG ln R
InanncT 8BRiogous lo thc procedure described ln Scheme i, Step F, Thc thlazInc pToduct
of Scheme 2, Step H can be prepared in a one pot 2 step reaction using benzoyl
Isothlocyanatc lB 8 IBRIUlcr 8BRiogoUs to thc procedure dcscllbcd ln Scheme l, Step (E Rnd
Ff, Thc IBixtuTc ls evaporated to 8 TcsKlUc Rnd cyciohcxRBc ls added. Thc Inlxturc Is
~0 heated to about 60 "C Rnd methvi tert-butyl ether ls added to dissolve the residue I he
solution ls filtered Rnd COBccniratcd 'to dryncss. Thc thiazine TiBg can thcB bc forIBcd in 8
WO 2016/176118 PC T/US2016/028896
manner Rnaiogous to thc pToccduTc described Til SchcIBc i, Step H to give thc pTodUct of
Scheme 2, Step H.
Step B
In Scheme 3, Step A, the Rniiine product of Scheme 1, Step N can be coupied with
8 hctcroaromatlc carboxpdlc acid Utihzlng coupilBg coBdltlons weri kBoivn IB thc Rrt. OBc
skIHcd ln thc Rrt vvi]l Tccognlzc that 'thcTc Rrc 8 BUIBhcT ot IBc'thods Rnd Tc8gcnts for amide
format]on 1 csu]t]ng &oIII thc react]on of carboxphc Rclds RBd Rmincs. PoT cxNIIpic, thc
I0 r'cac'tlon of Rn RppI'opTIRtc RBlIinc Avith Rn Rppropl'late Rcid IB rhc prcscncc of 8 couphng
Tcagcnt Rnd Rn RlrllBc base sUch Rs DIPEA oT trlcthvlaminc, xvIH glvc R compotuid of
Schcnlc 3, Step A. CoupilBg Tcagcnts ]nchKkc CRTbodlilnldcs such RS DCC, DIC, EDCI,
Rnd Rrontatic oxm les sUch Rs HOBt Rnd HOAt. Addltlona]1$", Uronlum oT phosphonlUIB
sRIts of non-nuclcophihc RBlorls such 8$ HDTV, HATU„PQBOP, Rnd P'v'HTOP oi' R cache
phosphoTic Rnhvdridc such Rs prop/'lphosphonlc Rnhpdr]dc (T3P'8)) cRB bc Used In place
of thc n lore traditional coupIing TcRgcBIs. Additives such Rs DMAP map bc Used to
cBI'lance 'thc I'cactlon. AltcITIRtivclv„ thc Rnihnc RIIIinc can hc Rcvlatcd Usnlg subStltuicd
bcnzopl cMQTldcs ln thc pl'cscrlcc ot 8 hase such Rs trlcthplaininc ol pp'Tldinc. In Schcmc
3, Step 8„thc pTotcctcd thiaz]nc Rmlnc can then bc dcpTotcctcd wv]th Rn oTgainc hase such
WO 2016/176118 PC T/US2016/028896
Rs pvrldinc RB«l 0-Incthplhvdrox j]RIBInc hvdTGOMGTidc IH solvcBls such 8s TtHF 8H«l
ethanol RBd RH organic hRsc such Rs p iridine to provide tl'lc coIBpouBd of Forliiula JR.
AlicIBRtivclp Rn inorganic hase such Rs lithium hpdroxidc in Blcthanol HIRE' hc used 'to
deproteet the thiazine to provide the conlpound of Formula 18.
Step A
Step 8
Altcrnativclye Bl Schclnc 4, Step A, thc aniline pl'oduc't of Schclnc l, Step 8 can
4c dcprotcetcd un«IcT st8ndRT«I. OondItions "vvcll kno'Atn in thc Rrt, lor example v'1th 8B
l 0 GTgRBlc hase such Rs p iridine Rn«l 0-n'lctl'1 jihvdroxflRBUHc hv«hocMGTIdc In solvents such
Rs 1I HF RBd ethanol to provide thc dcproteetcd dlRGUHG coBLpouBd. Altcrnativclv RB
IBGTgaruc 4Rsc such Rs lithluln hvdroxidc IB DlcthRnol Inap' hc used foT thc dcprotcctloB to
pTovldc thc dcplotcctc«l «48tnino colnpouBd.
ln Scheme 4, S'tcp He thc dcprotcctc«l diRBUHG conlpouBd ORB then hc sclcc'tlvclv
l5 couple«l Rt thc aniline Rnnno group &vith R hctcTGRTGDlatlc calhoxvllc Rcl«l utilizing
coupling conclltions lvcll knovLtn ln thc art to pTovldc thc eonlpound of IFGTmula 18. 0nc
skIHcd ln thc Rrt vvill Tccognlzc that 'thcTc RT'c 8 nuinhcr ot IBc'tho«ls Rnd Tc8gcnts ior RIBIdc
foiIBRt]GH 1 csUlting &GIII thc react]GH of carhoxphc Rclds RBd RIBIncs. FGT cxNBplc, the
r'cac'tlon of Rn RppI'opT1Rtc RIB1Bc&vith Rn RppI'opT1Rtc Roid ln thc prcscncc of 8 coupling
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Tc8gcnt and RB arninc b8sc sUch as DIPEA oT tTicthy]aininc, wi]] pTovidc 8 coInpound of
FOTIBU]a ]a. Coup]ing reagents include carbodiinlides such as DCC, D]C. EDCI, and
aroinatiC OXiIBCS Such aS HOBt and HQAt. Addit]OBR]]ye UTOniuin Or phOSphoniurn Sa]tS
Of Bon-BUC]Cophi]IC Rnlons SUCh RS HBTU„HATL', PyHOP„and Py]3rOP OT 8 eye]le
phosphoric anhydride such as propy]phosphonic anhvdride C'T3PS3) can be used in p]ace
of i]'lc Blor'c tl'Rdl'tiona] coup]ing I'cagcnts. Additives such as DMAP ITIRy bc Used ro
CnhaBCC ihC TCRCtion.
Step A
~.Q~.
Step B
'~MA.
„ F
e
A]ternative]y, in SChCIBC 5, thC brolnide pToduet Of SChenle ]., StCp M 1S Converted
to 8 pr'otcctcd Mu]iBc Using trif]uoroacctMnidc, coppcT Iodide, 8 dlMninc such as trans,
Taccinic-N, N -dinlcthy]-] „2-cyc]ohcxane clianunc, RB inorganic base sUch Rs potassiuin
C81boBatC, and Sodiunl lodldC With heating to about ]00-]30"C io giVC thC plotCCiCd
RIB]iBC product Of SchCIBC 5„StCpA. ThC pTotCctCd MnhnC RBd thiRZIBC MnlnC CRB 'thCB
be deprotected stepwise. The trif]uoroacetarnide can be hydro]yzed using a base such as
7 N arnnloB18 In Blcthano] to give an anl]inc RBd protcctcd thiazinc, t]'lc sanlc prodUct of
Schcinc ]„StepN. Thc thiazlnc cRB then bc dcpTotcctccl. UIKIci' conditions wc]] known in
WO 2016/176118 PC T/US2016/028896
tj'le art RBd described iB Scherrle 4, Step A using 0-Tnethyjhydroxyjarnlne hydrochlorKle
in a solvent such as ethanol and l HF with an organic base such as pyridine foHovred by
heating 'to Rbout 55 C or stlrrlng at rooIB temperature foHGwed by coBcentratlon and
purijication to give the product of Scheme 5„StepB. Alternatively, the order of
deprorectloB could be reversed with the IhlazlBe depl'otected fll'st RBd the 8Blilne
deprotected last.
The joHowlng prepar8tlons alld examples further lHELstlate tile lnveBtlon.
l0
PT'ep81'Rtlon l
(2S)-l-Trityloxybut-3-en-2-ol
OH o~y
ScheIne l, step A: Stir trlmetjlyjsujjonluln Iodide (j93.$ p„948. 2 Bllrloi) ln Tjjp
(l 264 Bll,) Rt. RTBbient teTBperature for 75 lrllnu'tes, Cool Tnixture to -50 C RBd Rdd BbutyHithiunl
(2.5 moj/L in hexanes, 379 mL, 948.2 mmol) via cannula, over a period of
l5 30 Tmnutes. AHow the reaction to graduaHy warnl to -30 "C and stir tor 60 rmnutes. Add
(2S)-2-trit/ joxymethyj oxiTRBe ( l00 g„3l6.l Blmol) poruoB wise„keeping the
temperature below -l0 'C. After the complete addition, RHow the reaction mixture to
warm to room temperature and stir for 2 hours. Pour the reaction into saturated
anllrloBlulrl chloride, separRte the phRses, ancl. extlRct the Rqueous ph8se with etjlyj
20 8cetate, Combine the orgaBlc lavers 8Jld dry over magnesium sujtR'te Filter 8Jld
concentrate tinder reduced pressure to give a residue. Purify the residue by sihca gel
chromatography, eluting with metjlyj T-butyl ether: hexanes (l0-l5', ~o gradient), to give
the title colnpound (56 22 g 54 /o) IES/MS In/z 353 (M 'Na).
Alternate Preparation l
(2S)-l-Trltyloxybut-3-en-2-ol
Scheme la, step A starting Tnaterial: Add tripherlyjmethyj cjHoride (287 g, 947.l
mmoj). DMAP (7.;l g. 63.l mmol) and triethylamine (l40 g, l 383.5 mmol) to a solution
WO 2016/176118 PC T/US2016/028896
of (2S)-hut-2-cnc-1, 2-dlo] (pTcpRTcd as ln SACS, 1999, ] 1, 8649) (64.5 g. 631 Inmo]) ln
dichk)roBIcthanc (850 In'). StlT foT 24 hoUTs at 24 C. Add 1 N 8qucous cltTlc Rcld (425
mL). Separate the layers and concentrate tile orgamc extract under reduced pressure to
dryncss. Add BlcthRB01 (900 mL) and cool to 5 'C foT ] houl. C0Hcct. thc solids hy
fk]trat]on and wRs]'1 with 5 ~C mcthano] (50 IBL). Dlscal d t]'lc sohds RBd coBccBtrRtc thc
mother liquor under reduced pressure to dryness. Add toluene (800 mL) and concentrate
to 8 B18$s Ot 268 g to ol3taln thc tltlc compouINl ( 129 g„67r~o) lB 8 48 wt 10 $0]utIOB of
to] ucnc,
10 PI'Cp81'RtNHI 2
] -Morpho]IBO-2-f(] S)-]-(trlty]oxymethy])RH v]oxyjethanone
Sci'lcnlc IR, step A: Add tctrahurV] RBBBonrunl hydrogen sulfate (83.2 g, 45.0
mmo]) 8nd 4-(2-ch]0Toacctv])morpho]lnc (638.50 g„3902. 7 BUB01) to R $0]ution of 1-
] 5 trity]oxybut-3-en-2-0] ( 832,4„25]9mnlo]) in toluene (5800 InL) that is between 0 and 5
'C. Add sodiuIII hydroxide (1008.0 g, 25202 mmo]) in water (]041 mi. ). Stn for 19
1'lours hctwccn 0 and 5 'C. Add watcI' (2500 BIL) Rnd to]uenc (2500 IBL). ScpRI'aic thc
lavcTs 8ncl was]'1 t]'lc or'g8nlc ex(ract with water (2 & 3300 mL), Concentrate thc organic
extract uBdcT reduced prcssure to dryncss. Add tolucnc (2500 BIL) to thc residue and then
20 add B-hcptaBc (7500 BIL) siov'ly. S'tn for 16 holus. C0Hcci il'lc Tcsulrlng $0Hds l3y
flltratNIB RBd wash with B-hcptarlc (1200 mL). Dry thc so]Nl under vacuunl to Ohtaln thc
tit/e compound (1075,7 g, 98"!4).
Preparation 3
1-(0-Hrolno-2-Auoro-phcny])-2-I (]5)- ]-(trlty]oxymcthy]) RHy]oxy ]cthanonc
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c '~
/
Scheme 18 step 8 Add a 1 3 M solution of Esopropvt magneslurn chloride
11'thiunl chloride coIIEplcx (3079 IBL, 2000 rrunol) 1BTHF to 8 solutEGB of 4-broEBG-1-
fluoro-2-Eodobcnzc (673.2 g„2237. 5 mrnoi) En tolllcBc (2500 B)E) Rt 8 Tate to DlalntREB thc
Tcac'tloB tcIBpcTatuTc below 5 C. StiT foT 1 l'louT. Add thc Tcsultlng GrlgBRTd solution
(5150 mL) to a solution of 1-morpholino-2-[(1 S)-1-(trityloxymethyl)allyloxy]ethanone
(500 g, 1093 Blmol) ln tohlcnc (5000 EI1L) at R Tate to IrlalntREB thc Tcactlon tclrlpclRturc
below 5 'G. Stir for 3 hours mamtamlng the temperature below 5 '"G, Add addi tlnal
prepared Grignard solution (429 IBL) and stlT foT 1 houT. Add 8 1 8 aqueous citric acid
10 solutloB (5000 B1L) Rt 8 Tate to mailltaiEE 'thc tcIBpcl'Rtur'c below 5 C. ScpRraic thc laycTs
ancl. Kvash thc olganlc cxtTact with watcT (5000 mL). ConccntTatc thc sohltlon ulldcr
reduced pressure to dryness. Add methanol (2000 mL) to the residue and concentrate to
giqrc thc title colnpound Rs 8 rcsiduc (793 g 73.4~/o potency~ 83 /0)
Preparation 4
1-(5-Bromo-2-f!uoro-phenyl)-2-[(l S)-1-(trltyioxymethy])aliyloxy]ethanone oxlme
Schcnlc 18 step (. Add hydE oxylaEBEnc hvdE ochk)E ldc (98 3 g) to 1-(0-broEHG-2-
fluoro-phenyl)-2-I( 1 S)-1-(trltyioxyIBcth tt'l)RHyloxy]cthanone (450 g, 707 BUBG1) Rnd
20 sodium Rcctatc (174 g) ln IBctharlol (3800 Bll,), HcR't 'thc sohltiorl to 50 G foT 2 houTs,
Cool to 24 'C and concentrate. Add water (1000 mL) and toluene (1500 mL) to the
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residue. ScpRTatc thc 1Rycr's Rnd cx'trRct. thc aqueous phase wl'th toluene (500 mL).
Combine the organic extract and wash with water (2 x 400 mL). Concentrate the solution
under reduced pressure to give the title colrlpound as a residue (567 g, 61A',4 potency,
88 /0).
PI'cparailon 5
tert-P uty 1 2-I (1S)-1-(trltyloxymethyi)aiiyioxy jacetate
iiW
Scheme 1, step 8: Add (2S)-1-trltyioxvbut-3-en-2-ol (74.67 g„226. 0 mmol) to a
10 solution of tetra-N-butylanImonium sulfate (13.26 g, 22.6 mmoi) in toluene (376 mL).
Add sodluln hydroxide (50,/o mass) BI watcI' ( 1 19 mL) followed bv ]el'f-butvl-2-
bTomoacctRtc (1 10.20 g, 565.0 Inmol). Stir reaction nllxtulc lor 18 houTs Rt. Rrnblcnt
tclTlpcTatuTc. PouT Into water, scparatc thc phRscs, and cxtrRct thc Rqucous phase v lth
ethyl acetate. Combine the organic layers and dry over magnesium sulfate. Filter the
15 mixture and concentrate under reduced pressure to give the title compound (77.86 g,
770/o). ES/MS m/z 467 (M+Na).
Preparation 6
(1E)-2-[(1S)-1-(Trityioxymethyi)aiiyioxy jacetaidehyde oxime
ii '
20
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Scheme ], Step C: Cool 8 So]UtloB Of tet t-buty] ' -[(1S)-1-
(tr]tv]oxymethy])RHy]oxyjacetate (7 ' 66 g 1 4 ' mmo]) m dich]oromethane (582 2 ml )
to -78 'C. Add a solution of diisobutylaluminum hydride in hexanes (1 mo]/L, 174.7 mL)
ClropvvlsC OVCE 8, pCllod 0] 35 InlnutCS Rnd Inalntaln thC tCIrlpCTatuE'C bC]OVV -70 C. StiT Rt
5 -/8 'C for 5 hours. Add hydrocMoric acid in water (2 mo] ]L, 192.] mL) to the reaction
mixture dropwise„keeping the temperature below -60 'C. AHov the reaction to graduaHy
warln to ambient tcIBpcr8tuTc Rnd stiT for 60 mlnutcs. ScpRE'Rtc thc 0Tg8nlc cxtlact Rnd
wash with saturated sodlurn bicarbonate. Dry the so]utlon over Inagrleslum su]fate, fi]ter,
and coBccntrRIc UBdcT I'cduccd pl'cssul'c to g!vc 8 residue. Dlssoivc thc residue EB
10 dECMoromcthanc. Add sodEUEB RcctRtc (28.66 g, 349.3 Bnnol), followed by
hydroxy]amlnc hydrocMorldc (18.21 g., 262.0 mnlo]). Stll' 8t Rlnblcnt tcIBpcTatuE'c ]or 18
houTs. PQUT!Bto w8tcT, scpRratc thc ph8scs, RBd cxtrRct thc aqueous phase with
dlcMOTonlcthRnc. COIYEblnc thc or'gaBlc 1Rycr's Rnd dry over Blagncslulrl sU]fate. Fi]tcr 'thc
lrllxtuTc Rnd conccntlatc Euldcr reduced plcssUI'c to glvc thc tlt]c colrlpouBd (68.38 g,
10].o/o). ES/MS m, 'z 386 (M-li).
PrcparatEOEI 7
(3RR,4S)-4-(TI'1tyloxvIBcth y])-3,38,4,6-terra]'lydro fill'0 [3,4-cj1 sox azoic
20 Scheme 1, step D: Cool a solution of (]E)-2-[(1S)-1-
(trlty]oxvmethy])a]]y]oxyjaceta]dehyde oxEBIC (55 57 g 143 4 mmol) ln tet t-buty] methy]
cthcT (717 mL) to 0 C. Add sodEUIB hypochloTltc (5/o En water, 591 mL„430.2 Bllrlo])
dropwise, keeping the temperature be]ow ]0 'C, Stir at 10 'C for 30 minutes. A]lov; the
TcactloB to warm to 15 C. StlT 8t 15 C foT 18 hours. Di]utc thc react]on fnixturc with
25 ethyl acetate and wash with saturated sodiunl bicarbollate. Separated the phases, v.ash
hc ol Panic phase with 8 5 /o sodEUBE hvdlogcn sujphltc solution RBd brlnc Dly thc
so]Ution ovcT BIRgBcsnlm sulfR'tc, h]tcr, RBd conccBtr8tc Under reduced pTcssuTc lo give 8
residue. Purify the residue by si]ica gel chromatography, eiuting with 50 so methyl tertWO
2016/176118 PC T/US2016/028896
buty] ether/dIch]ororncthanc: hcxancs (20-27,~0 gradIcnt), to g1vc 'thc tIt]c coIBpouBd
(35.84 g, 65'.io). ES/MS m/z 408 (M+Na).
Prcparatton 8
(3RR..4S,6RR)-6R-(5-Bromo-2-f]uoro-pheny])-4-(trIty]oxymethy])-3, 3R,4.6-
tcirahyclro fuI'o [3,4-cj1soxazoic
0
/~ 0 ''0
SchcIBc 1 step F Cool a so]utIon of 4-bromo-]-Auoro-2-Iodo-benzene (86,94 g,
288.9 mmo]) in YHF (144.5 mL) and to]uene (1445 m]L) to -78 'C. Add n-buty]lithium
10 (2.5 M in hexanes, 120 mL, 288.9 BIIBO]) dropwise, keeping the temperature below -70
'C, Stir for 30 mnrutes at -78 'C. Add boron triAuoride diethyl etherate (36,5 m]., 288.9
mmoi) dropwise, keeping tentperature below -70 'C. Stir the solution for 30 minutes at-
, 8 'C. Add a solution of (3',4S)-4-(trity]oxymethy])-3„3R„4,6-tetrahydro furo[3, 4-
cIIsoxazole (55.69 g„144.5 mmol) In THF (482 mL) dropwIse to the react1on„over a
] 5 period of 30 minutes„keeping temperature be]ow -65 'C. Stir at -78 'C for 90 minutes,
Rapid]y add saturated ammoniuIII chloride, keeping tentperature below -60 'C. Pour into
brine, and extract the aqueous phase v;ith ethyl acetate. Combine the organic extract and
dIV ovcT BIagncsmITI sulfate. FI]tc1 RIN1 conccntTRtc under reduced pTcssurc to gIvc R
TcsNhLc. PuTIfv thc TcsN]uc by sthca gc] chTonlatographv, ch1ting wtth a gradIcnt of ].00,~0
20 hexanes to 30'.io hexanes/70 so diethyl ether, to give the title coInpound (36.52 g, 45'lo).
ES/MS rn/'e ( Br,' Br) 560/562 [M+H].
A]tcTBatc PTcpaTatton 8
Scheme la„step 0: Heat a solution of 1-(5-bromo-2-fluoro-phenyl)-2-[(1S)-1-
25 (trtty]oxymethy])a]]y]oxv Iethanone oxtme (458 g, 502 mmol) and hydroqumone (56.3g
511 IBTno]) In toiucnc (4000 BI];) to Tcf]ux uBdcT mtrogcB foI' 27 hotITs. Coo] thc so]11tIon
WO 2016/176118 PC T/US2016/028896
to 24 C Rnd Rdd Rqucous sodlurn CRTbonatc (800 IBL), Scp8TR'tc thc iaycTs and extract tl'lc
aqueous phase with toluene (300 ml. ). Combine the organic extract and wash with water
(2 i 500 mL). Concentrate the solutiollunderreducedpressure to give aresidue. Add
lsoplopyl Rlcohol (l 500 mL) and hcRt to lcflUx. Cool to 24 'C RBd coHcct thc solKIs by
filtration. Dry thc solid under vacuunl to obtRIB Ihc title coIBpouBd ( l2 g 75/0).
Preparation 9
l -[(3RR,4S,68S)-68-(5-Bromo-2-fluoro-phenyl)-4-( trj tyloxvIBcthvl)-3, 38,4,6-
tetrahydro fu To [3,4-c]isoxazol- l -yl]ethanone
Scheme l 8„stepE: Add acctvl chlor1dc (35.56 g., 503.9 mnlol) to 8 solution oi
(3RR,4S,68R )-68-(5-bronlo-2- fI uoTo-phcnvl)-4-(trltyl oxymcthyl)-3, 38,4,6-
tetrahydrofuro[3, 4-cjisoxazole (235.3 g, 420 mmol), DMAP (5.l3 g, 42.0 mmol), and
pyrldlnc (66A5 g, 840.l Blmol) ln dlchioroIBcthanc (720 B)E) uIKIcl' BItrogcn„malntalnlng
l 5 internal temperature below 5 'C. Stir for l hour and then add water (300 mi.) and l M
sulfuric acid (300 mL). Stir the mixture for l0 minutes and allow the layers to separate.
CoHcct il'lc organic extract and wash with satuTatcd sodium cRI'bonatc (500 IBL) and watcI'
(500 B)E,). Drv thc solutloB ovcl' magnesium suliatc. FlltcT and conccntTatc under
reduced pTcssuTc to glvc l -[(38R.,4S,68S)-68-(5-HroIBo-2-fjuoro-phenyl)-4-
20 (tr~tvloxymethyl)-3 3a 4 6-tetrahydrofuro[3 4-c]lsoxa7ol-l-yl]ethanone (235 g 93'io) as a
PI'CpRI'Rtlon l 0
1-[(38R.,4S,68S)-68-(5-Bromo-2-fluorophenyl)-4-(hydroxynlethyl)tetrahydro- l H, 3Hfuro[
3„4-cj [ l,2]oxazol-l-yl]ethanone
WO 2016/176118 PC T/US2016/028896
Ho=
Scileme 2, step A: in a 20 Ljacketed reactor add acetyl chloride (290 mL, 4075
BHBG]) to 8 solution o1 (38R,4S.,68R)-68-(5-broino-2-fluoro-phcEI vj)-4-(trltyjoxymcthyj)-
3,38,4,6-tetra]zydrofuroj 3,4-cjisoxazoje (]996 g, 3384 HHHO]), DMAP (56.0 g, 458
EHmoj), pyridine (500 mL, 6180 mmol) in dichloromethane (10 L) Under nitrogen
BlalntalnlBg lBtcTBR] tcBlpcTatuTc bcjovv' 10 'C. Aftci' coDlp]ctc Rddltlon (1 hour) vv'arm to
20 C RIEd stlT ovcrrught, . 1]TcactioB is lncoIBpictc„Rdd Rcctyl ch]oridc, DMAP, pyrldlnc,
and dich ]GTGIHethane until comp]ete reaction is observed. Coo] the reaction mixture to 0
'C and sjolvjy add water (5 L), stir the reaction mixture at 10 'C for 30 minutes and ajjmv
]0 thc iayci's to scpalRtc. Coj]cct thc GI'gRnic cxtTact ancl. Rvash thc aqueous Rvith
dkcMoromethane (1 ]L). YVash the combined orgmic extracts lvith ] N aqueous
jlydrochjorlc acK] (2 x 4 L), extract thc aqueous with dlchjoromctjlanc (2 x 1 L). %'ash
thc coBlbincd GI'gRnlc extracts "vvith "vvatci' (4 L) ancl. I'cmovc thc soivcBt, Under reduced
pTcssuTc give tota] vo]unlc of approximate]y 5 L. Add 90/o fortnlc acid (1800 Bli) RIEd
and at anlbient temperature fol 3 davs ggtarEB to 40 C for 2 hours t]lcn rcmove th
solvcllt Ulldcl' reduced pI'cssul'c. Dilute thc residue with Blc'thanoj (4 L) RM] slowly add
saturated aqueous sodiUIB cRE'bonatc (3 L). Add so]ld sodBBB cRE'bon8tc (375 g) to 8d]ust
the pH to 8-9. Stir at 45 'C for 1 hour then cool to ambient temperature. Remove the
solids bv flitrRtloB lvashing with Encthanoj (4 x 500 EBL) tjlcn trcRt with N aqueous
20 sodluln hydroxide (100 mL) and staM] at anlblcnt. tcBlpclRtllTc foT 1 hour. RcDlovc thc
so]ids lly fHtratlon, washing wvlth BlcfhaBG] (2 x 100 B'EL), Evaporate thc so]vent UIEdcr
Tcduccd pTcssUTc and pRTtltloB thc Tcslduc bchvccn ethyl acct8tc (5 L) REId &vatcr (2 L).
ExtTact thc aqueous wl'th ethyl acciatc (2 L) and wash thc conibincd orgREUc extracts &vith
bTIBc (2 x 1 L). Rclrlovc thc so]vent Unclcl Tcduccd pTcssUTc, add Blct]ly] tcE"t-buty j ctllcT
25 (2.5 L) and evaporate to dryness. Add methy] tet t-butyl ether (4 L) and stir at 65 'C for ]
1'loUT cool to ambient 'tcnlpcTatUI'c and collect thc solids by filtration, washing v'ith Blcthvj
tePt-butyl ct]lcr (3 x 500 mL). Dly UM]ci' vRCIBB to 8 bclgc solid. . Heat t]us so]ld ln
to]ucnc (7.5 L) to ] 10 C Utltli fui]y disso]vcd, cool to 18 C ovcT 1 ]'loUT, RBd stir at this
WO 2016/176118 PC T/US2016/028896
temperature for' ]. houT, iVRTIB to 40 C and when pTcclpitatc fornls, coo] to 18 ~C once
more. Stir for 45 minutes then co]lect so]ids by fi]tration, washing with to]uene (2 && 500
mL). DQ thC Sohd UBdCT vacuuln to obtain thC tlt]C compound (443.] g, 36'ro„93'rro pirrlty
by LCMS). Evaporate the hitrate under vacuum to give a residue. PUTI]y the residue by
si]lcR gcl f]ash chromatography clutlng with 20ro to 100ro cthv] acetate !H 1&ohcxanc
S]urry thc product contaimng fr'actions IB Blcthyl tePt-butv] cthci' (2 L) at 60 C for 30
irllButcs, .cool to RDibicnt tcinpcratILrc. , 8nd. co]lect thc so]lds by ]1]tratlon„washing with
methyl /eI T-bu'ty] ether (2 & 200 BI1 ), DTv thc solids UBcicr' vacuum to give thc tlt]c
coBlpound RS 8 bCigC crysta]]IBC Sobd (304 g, 24 ro, 88~ro purity by LCMS). Evaporate thC
10 fi]tratc under vacuum ro 8 residue. Purify thc icsiduc by silica gcl f]ash chIGITIRtogIRphy,
ciutlng vvlth 20 ro to 100ro cthvi acctatc ln EsolicxRnc to give thc tltic coBlpouncl. ]37.8 g.,
5or'o, 88 ro purity by LCMS). ES/1' S: m'z (' Br/ 'BT) 360.0/362. 0 I M-'Hj.
AltcTBRtc Pi'cpaiatlon 10
Scheme 2, step A; Add ].-I(38R„4S, 68S)-68-(5-bromo-2-f]uoro-pheny])-4-
(trih]oxymethy])-3, 38,4,6-tetrahydrofuroj 3,4-cjisoxazo]-]-y]jethanone (69 g, 114.5
mirlol) to 8 15 C so]Ution of/i-to]ucncsu]foBlc acid DlGBGhydTaic (2.2 g, 11 45 mino]),
dich]oronlcthanc (280 Bll,) RBd mcthano] (700 B'IL). Stir for ] 8 houTs 8nd then rcmove
thc so]vent. UIKlcT reduced pr'cssur'c, Di]utc thc residue with dich]or'omcthRnc (350 mL)
20 and add 1 M aqueous sodium carbonate (140 mL) and water (140 mL). Separate the
layers and evaporate the orgamc layer Under reduced pressure. Add toluene (350 mL) to
t]'lc Tcsiduc Rnd heat to redux foT 1 ]'louT. Coo] to ]0-15 C at 8 I'Rtc of 10 C/hour.
Col]ect the so]ids by fi]tration and wash with to]uene (70 m]L). Dry the so]id under
vacmim to obtain the title compound (30 g., 65oro) as a grey so]id.
Prcparat]GH 11
(3aR,4S„6aS)-]-Acety]-68-(5-bromo-2-f]uoro-pheny])-3, 38,4„6-tetrahydro]uro I 3,4-
Cj Isoxazo]e-4-Carboxy]IC RCK1
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/0 HO~&
Scheme 2, step 8: Add water (2 L) to a suspension of 1-[(3RR,4S,6RS)-6R-(5-
bromo-2-fluoropheny])-4-(hydroxymethyi)tetrahydro-] H, 3H-fun[3„4-cj[1,2joxazol-lyi
jethanone (804.9 g, 2177 mmoi). (2,2,6,6-tetramethyi-piperidin- 1-yl)oxyi (40.0 g. 251
Inmoi) in Rcetonitrile (4.5 L) in a 20 L Jacketed I'eRcior Rnd cool to an internal
temperature of 5 C. Add (dtacetoxytodo)benzene (1693 g, 4993.43 mIBoi) poI'tionvvlse
over' 30 mtnutes, Control 'the exothernl ustng TeactoT coohng Rnd theB hold at 20 C UBtll
LCMS shows complete reaction. Slowly add a suspension of sodium bisuittte (70 g,
672.68 mmol) m water (300 mL) at ambient temperature, maintaining the internal
10 temperature belOw 25 C. Stir' foT 30 Ininutes and then cool 'to 5 C. Add wateT (2 L),
then ~iowiv add 47 wtlo aqueous sodrum hydroxtde (780 mL) over a pertod of 1 hour
maintaining the internal temperature below 10 '"'C. Add ethyl acetate (2 L) and isohexane
(5 L), stir vigorousiv RBd sepRTate the layers. ExtTact the btphas1c organic 1RyeTs wtth
wRteT (1 L) RBd wash the cornbtned aqUeous wtth Methvi tet/-butyl etheT (2.~L), Cool the
15 Rqueous extTacts to 5 C and slowly add 37,~o hydTochioTIC acid (1.4 L) oveT 30 TMnutes
maintaining the internal temperature around 5 "'C. Add ethyl acetate (5 L), separate the
layers RIK1 wRsh the oTgaruc w]th brme (3 & 1 1,), Ex'trRct. the coB'Ibtned aqueous extracts
with ethyl acetate (2.5 L), wash the combined organics with brine (1 L). then dry with
sodium sulfa'te, RBd triter. Dilute ilte organics w1'th heptaBe (2.5 L) and evaporare to
20 dryness under reduced pressure. Add methyl /err-butyl ether (1.5 L) and heptane (1.5 L)
RIK1 evapoTate to drvness. Add heptane (2.5 L) and evRpoTate to dryness twtce, Add
heptane (500 mL) and methyl tert-butyl ether (500 mL) and stn at 40 'C for 30 minutes
then coHect the preclpltate by flltTRtloB, wRshrng wtth heptane/methyl k'eP/-butvi ethe1
(1."1, 1 1,) then O'Iethyl /Crt-butyl eti'IeT (3 ~ 300 TBL) and RIT dTy to g]ve the tt tie compound
2& as a be&ge crvstailme soitd (779 g 9N'0) FS MS m'7 ( "Hr'""Hr) «74 0'376 0 [M-', Hj
[ojI«"' = -19.0 ' (C=1.004, chloroform).
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A]tcrBRlc PTcpRTatlon I I
Scheme 2, step 8: Add water (150 mL) and
acetonitril
(150 mL) to 1-[(4S,68S)-
68-(5-bromo-2-f]uoro-phelly])-4-(hydroxylnethy])-3, 38,4,6-tetrahydrofuro[3, 4-cjisoxazo]-
1-y]]ethanone (30 g, 73.3 mmo])„T]EMPO (].14 g„"3;.0 mmol) and (diacetoxyiodo)
5 benzene (51.9 g, 16] mmo]). Cool to 15 'C and stir for 2 hours. S]ow]y add sodium
thlosulfatc (21 g) Rnd potassluIB carbonRtc (22 g) In water (150 IBL) at REBblcnt
tcBlpcIRtuTc. Stir fol 1 hour RBd then Rdd Incthyi k'el. /-buty] ether (150 lrlL). ScpREatc thc
lavcTs 8ncl adjust t]'lc pH of thc Rqucolls iaycT to 2-3 with concentrated sll]fuTIC acid, Add
cthvi Rcctatc (150 EBS) RBd separate thc ]RycTs. I'vaporatc thc org8Blc ]8ycr Io dryBcss
10 under reduced pressure. Add B-heptane (90 mL) and heat to reflux for 1 hour. Cool to 1&
C REId then co]lect. thc pTcclpltate by flltlatlon, v'Rshlng v'1th B-hcptanc (90 IBIL). l3ry
uBdcT vacuum to glvc thc tlt]c compound Rs R white solid (27 g, 98,~0).
PI'cpal'RtloB 12
(38R,4S„68S)-1-Accty]-68-(5-broIBo-2-f]uorophcny])-N-methoxy-N-mcthy]tetra]'lydro-
1H.3H-furo[3, 4-c][1,2]oxazole-4-carboxamide
Scheme ,. step C: IB 8, 10 L jacketed lcactol'„cool 8 so]utloEI of (38R.,4S,68S)-Iacety]-
68-(5-bromo-2-f]uoro-pheny])-3, 38,4.6-tetrahydrofuro [3,4-c]1soxazo]e-4-
20 carboxylic acid (7/1 g„2019rrnno]) in dichloromethane (, .0 L) to 0 'C lmder nitrogen
Rnd Rdd CDI (400 g„2421mmo]) portlonwlsc ovcl' 40 minutes. Cool thc TcRctol ]acket to
-20 C 8nd s'tlT foT ] houT 8Bcl then Rdd N„O-dlrncthy]hydroxy]RIBlnc hydroch]orKlc (260,0
g, 2612 mmo]) poIComvise over about 30 minutes. Stir at -20 '"'C for 1 hour, at 0 'C for 2
hours, and at 10 "C for 7 hours. Add CDI (175 g, 1058 rrnno]) and stir at 10 "C
25 overmght. Add further CDI (]80 g, ]088 mmol) at ]0 'C and stirred for ] hour then add
N O-dBIIethy]hvdroxy]alIBBC hvdroch]orlde 1140 ~ 1407 mmo]) and contmue stlmn~ at
10 'C. Ifthc IcRctlon ls lnconlplctc, fuIthcI charges of CDI fo]]owed by N, OWO
2016/176118 PC T/US2016/028896
dirncthy]hydroxy]RTMBc hvdToch]0Tidc can bc BMdc Unti] conlp]ctc I'cRctlon ls obscTvcd.
Cool the reaction mixture to 5 'C and wash with 1 N aqueous hydroch]oric acid (5 L)
then 2 N aqueous lrydrochloric acid (5 L). Extract the combined aqueous solution with
dich]oromcthanc (1 L)„coDlblBcthc organic cxtlact Rnd vvash with watcT (2.5 L)„1 '8
5 aqueous sodiunl hydroxide (2.5 L), Rnd wRtcT (2." L), dry ovcT Blagncsium su]fRtc, fl]tcr,
and evaporate under reduced pressure to give a residue. Add methyl /crt-buty] ether (3 L)
Rncl. cvapolatc UndcT reduced plcssUI'c. Add further methyl /er/-buty] cthcT (2 L) RBd stll'
Rt 50 C foT 1 hoGT„cool to 25 C RIK1 stir' foT 30 Inlnutcs, Co]lect thc Tcsu]ting sohds by
tl]tTatlon wRsh wrth Btcthv] /crt-buty] cthcr (~ x 300 mJ ) Rnd dry GBdcI' YRcuuTB Io glvc
10 rhc tlilc conlpound (760 g„88', ~o) Rs 8 white so]id. ES/MS: Bl.'z (' Bl/"Hr) 417.0,'4]9.0
[M-l-]-1j.
AltcrBRtc Preparation 12
Scheme 2, step C: Cool 8 so]utlon of (38R.„4S, 68S)-i-accty]-68-(5-bromo-2-
Auo To-phcny])-3 „38„64-t,ctrahydro furo [3,4-cjisoxazo]c-4-carboxylic acid (27g, 70.7
mmol) in N, N-dimethy] formamide (135 mL) to 0 'C under nitrogen and add CD] (14.9 g,
91.9 mlnol). Stir for 1 hour and then add Yl,O-dimethy]hydroxy]amine hydrochloride (9.0
g, 92 BIIBol) and trlcthy]RIBInc (]4.3 g, 141 Inmo]), SGT Rt 15 C for ]6 houTs, Coo] thc
I'caction B'BxtuTc to 0 C RBd Rlid 0,5 M Rqucous sU]fuTIC 8cld (675 mL), S'tlT foT ] houT.
20 Collect the resulting solids by filtration. Slurry the solids in methyl /ert-buty] ether (90
lrlL) foT 1 houl. Co]lect thc so]lds ily ]lltlatlon, wash vvlth Blcthvl /ePI-buty] ether (30
B'lL). Dly GBcicr' vacuum to glvc thc tlt]c coIBpouBd (23 g, 78/Q) Rs 8 so]KL
PI'Cparailon 13
]-[(38R.,4S,68S)-]-Accty]-68-(l-brolno-2-f]uoro-phcny])-3„38„4, 6-tctrahydro furo[3, 4-
C]isoxazo]-4-y] ]Cth Rnone
o~o
SchcIBc 2, step D: in 8 20 Ljacketed TcRctol, cool 8 solution of (38K,4S,68S)-]-
WO 2016/176118 PC T/US2016/028896
acety]-68-(5-bromo-2-f] uoropheny])-N-methoxy-N-methy]tetrahydro-1 H, 3H-tuTo [3,4-
cj[1,2joxazole-4-carboxamide (654.0 g, 1536 mmo]) in THF' (10 L) to -60 'C and add a
".2 M solutioEI of methylmagnesium bromide in 2-methyltetrahydrofuran (660 BIL, 2110
Inmol) dropwIse, whI]e mamtaInmg the mterna] temperature be]ow -40 'C. Sttr the
5 reaction mixture at -40 'C for 30 mimEtes then coo] to -50 'C and add a sohEtion of 1 5
aqueous hydroch]oric acid (2 L) In 1HF (2 L) BlanltREB]Bg the interEIR] teEBperaruEe be]ow
-38 ' C. ]BCTease the temperature to 10 C RBd add ethy] 8cetate (5 L) and water (1 L), stET
RIK1 RHow InternR] temperature to I'each 5 C and separREe the ]ayeTs, Extract the aqueous
layer' with ethy] 8cetRte (1 L) and contbine the or'ganIc extracts. Vv ash the organic
10 extracts with v.ater (2 L) and extract the aqueous layer v.ith ethyl acetate (1 L). Combine
the oEgarElc exiTact and wash vvlth bIIne (3 x 2 L) then dry over B18gnesIUITE su]fate„ ttlteT,
and evRporate UndeT Teduced pTessUI'e to 8 residue. Md cyclohexane (2.5 L), stn at 60 C
for 1 hour then at 20 'C for 30 minutes, and co]lect the so]id by filtration, washing v.ith
cyciohexRne (500 mL). Dry the soiK1 UIEder vacuuITE to obtREB the ttt]e coIBpound as 8
]5 white so]id (565 g, 99'!~). ES/MS: m/'z (' Br,' Br) 372.0/374. 0 [M+I-ij„[EI]D' .-—-58.0 '
(C=].000, chio''Of o'LIB.
A]ternate Preparation 13
Scheme 2, step 0: Cool a solution of (38R,4S,68S)-]-acety]-68-(5-bromo-2-
20 f]uoropheny])-b-methoxy-N-IBethy]tetrahydro-]H„3HI-]UEO[3, 4-cj ~ ]„2Ioxazo]e-4-
carboxamrde (4,0g, 9.59 mBEo]) In THE (60 mi) to -5 'C and add 8 3.0 M so]utIon of
methy]magnesium bromide in 2-methyltetrahydrofuran (5.0 mL, 15 mmol) dropwise,
whI]e DERintaiBBIg the EnieTB81 'teDEperatuTe between -5 Rnd 0 C. StII' the I'eactron mixrure
between -0 8Bci 0 OC for' 60 IBIMEtes therE add 8 so]utton of saturated amrnonIum ch]oTide
25 (20 m]L). Add methyl tert-butyl ether (40 ml. ), 8]]ow the internal temperature to reach 5
'C and separate the layers. Evaporate the organic layer under reduced pressure to a
residue. Add n-heptane (50 mL)„stir, and co]lect the solid by fE]tration. Dry the so]id
UBdeT vacuum to obtaIB the tIt]e cotnpouBd Rs 8 so]Id (3.0 g. 77 zo).
Preparation 14
] -[(38R.,4S,68S)-68-(5-Hromo-2-f] uo Topheny])-4-(], ]-dIf]uoroethy])tetrahy dro-] H, 3Hfuro[
3.4-cj [1.2joxazo]- 1-yljethanone
WO 2016/176118 PC T/US2016/028896
Q l Q
Scheme 2, step E: Add ]-[(38R,4S,68S)-]-acety]-68-(5-bromo-2-f]uoro-pheny])-
3,38,4,6-tcrrahydrofuro[, 4-c]isoxazo]-4-y]jcthanoTIc (5.08 g, 13,6 mTBG]) In R sHll, ]c
portion to a stir ed suspension of dif]uoro(moqpho]ino)su] fonium tetrafluorobo rate (]0.02
g, 39.18 HHB01) ln anhydrous dlcMoronlcrhanc (100 HlL) Rt 0-5 OC. Stir 'thc HuxtuTc for
10 minutes Rnd Rdd tllcthy]RITHBc trlhydroAuorIdc (4.5 B1L, 27 BHI101) dTopwlsc ovcl 10
minutes. StiT t]'lc TcRctioTl BuxtuTc IB thc Ice-bath (or 8 hours thcB WRTTB to RIBbicB(,
temperature Rnd stiT ovcTBighr. Add s8turatcd aqueous sodium CRrboBatc (100 IBL) and
stir for 1 hour. Separate the layers and extract the aqueous with dichloromethane (2 x 50
]0 mL). Conlbme the orgamc extracts and wash WI(h saturated aqueous sodium bicarbonate
(100 mL), 2 N aqueous hydroch]or]c acid (2 & ]00 mL), and brine (100 mL). Evaporate
to dryncss ro 8 Hght bI'own soHd Rnd disso]vc ln Hlcthyl /eet-buty] cthcl' (300 HlL) at 60
'C. FlltcT thc llot so]utlon and cvapol ate thc 11]tratc to give 8 brown so]KI. (5.3 g, 8]'/o.,
82o/o purity by LCMS) that is used. without further purification, ES/MS: m!'z (' Br/ "Br)
15 393.8/395. 8 [M+Hj.
A]teIIIate Preparatln 14
SchcTBc 2, step E: Aild Xta]F]uor-M'8) (].21 kg, 4,73 mo]) ln portions to 8 surrcd
sohltlon of 1-[(38R4S 68S)-]-Rcetv]-68-p-bromo-2-f]uoro-pheny])-3 3a 4 6-
tctrahydrofuro[3, 4-cjlsoxazo]-4-$ ljcihanonc (563 g, 1.51 Biol) ln anhydrous
20 dlcMGTGIBcthanc (3 L) at, -14 C. Stir thc InlxtllTc foi' 10 Bnnutcs Rnd Rdd trlcthy]RITHBc
trjhy&]ro(]uoridc (550 g, 3,34 mo]) dropwisc ovcT 0 minutes. StiT 'thc TcactioB mixture Rt
-10 'C for approxlmateiy 10 hours then warm to ambient temperature and stir overnight.
Add 50,~o aqueous sodium hydroxide (!50 BIL) slowly, B1RHI'taiBHlg thc HltcTB81
tcIrlpcTatulc bciovv 10 C„thenRdd WRtcl (L5 IL) Rnd saturated aqueous sodlunl hydrogen
25 CRT'boBatc (] L) RBd stU' foT 30 TMBIHcs. Separate thc laycTs RBd cxtTact thc aqueous with
dlcMGTGB1cthRnc (1 L). Combine 'thc orgarnc cxtl'Rcis Rnd wash wl'th bl'Hlc (3 L), 2 5
aqueous hydrochloric acid ( 5 L), and brine (3 L). Evaporate to give a residue and purify
WO 2016/176118 PC T/US2016/028896
by sl]icR gci chTomatogTaphy c]utlng with 50-] 00/o d]ch]oromcthanc ln 1$0-hcxanc then
10".0 methyi /e]"t-buty] ether in dich]oro]nethane to give the tit]e compound as a white
powder (467 g, 73'4, 94'/o purity by LCMS). ES/MS: m z (' Br/" Br) 393.8/395. 8
[M-l-Pi j.
Preparation 15
(38R.„4S, 68S)-68-(5-Bromo-2-f]uoro-phcny])-4-(], i-dlf]uorocthy])-3, 38,4,6-tetrad «Iro-
]H-fuTQ[3, 4-cj]soxRzo]c
Schclnc 2, step 1: Add 37vi't/o aqueous hydroch]orle ac]d (1.3 L, 16 IBQ]) to 8
so]u'tloB of ] -[(38R.,4S,68S)-68-(5-bromo- -f]uorophcny])-4-(], ]-
dif]uoroethy])tetrahydro-] H, 3H-furo[3. 4-cj [1.2joxazo]-1-yijethanone (570 g, ].45 mo]) in
1,4-dloxRnc (5 L) ln 8 10 L jacketed lcactor RB«i stn at 100 'C fol approxln1Rtciy 3 hours
or until LCMS shows comp]etc react]on. Coo] the react]on rmxture to 10 'C„d]lute with
] & water (1 L) and add a mixture 50 wtzo aqueous sodnlm hydroxide sohltlon (800 mi.) and
wRtcT (1 L) s]ow]y, ntaintain]ng thc ]Btcrna] tcTBpcTRtuTc bc]ow 20 ~C. Add cthy] acctatc
(2.5 L) and stir vigorously, before separating the layers and washing the organic phase
wi th bTiBc (2 L), further bTlnc (1 L')„Rndwater (] L). Drv ovcT IBRgl]csium su] fate, fl]tcr
and CQnccntratc tQ dryncss 1]ndcr reduced prcssure IQ give 8, ] cs]duc. Add cyc]Qhcxanc
20 (2.5 L) Rnd cvapol'Rtc ro dryncss thcB Tcpcai ro obtain thc iltic conlpound Rs 8 bTown oi]
(527 g, 89"i&„86&'opurity by LCMS). ES/MS: m/z (' Br/ Br) 35].8/353. 8 [M-l-H j.
Preparation 16
[(2S,3R.„4S)-4-Am]no-4-(5-brolno-2-f]uorophcny] )-2-( 1,1 -d] fiu QTocthy 1)tet]'aily«iTQ turRB-
3-y] jlrlcth8no]
WO 2016/176118 PC T/US2016/028896
F
OH
Sci'lcnlc 2, step 4: Add zinc powder (6.0 g, 92 BBBG])to 8 so]utEOEI ot
(38R,4S,68S)-68-(5-bromo- -fluoTG-p]'lcnvl)-4-(l, ]-dlf]uolocthy])-3, 38,4,6-tctrahydro-
1H-furo[3. 4-cjisoxazo]e (5.06 g, 13.4 mmo]) in acetic acid (100 m]L) at ambient
tcIBpcl'Rtur'c and stir ovcllligh. Dlhltc Ehc mixrure with ethyl acetate (200 mL) and v'atcl'
(300 B)E) and stll' vlgol'ous]y whl]c adding sodBHII caTboBRic (97 g, 9]5 mlno]). ScpaTatc
t]'lc 1RvcTs Rnd wash thc orgRnlc layer with bnBc (2 && 200 EBL), dry ovcT magnesium
4EE]fate f!]ter and concclltratc to Evc 8 residue Purify Ihc Tc4Edue bv &E]ICR gc]
chrGEBatography c]Utlng with Ã~o Eo 100 so IYEcthyl EeE'f-buty] ether IB lsohcxanc Eo glvc thc
]0 tlt]C COITEpouBC] RS 8 Waxy So]K1 (4,67 g, 89 Xo, 90zo purity by LCA']S). ES/MS; EIE'Z
(' Br/ Br) 354.0/356. 0 [M+Hj.
AltcTElRtc PE'cpalatlon 16
Scheme 2, step G; Add zinc powder (200 g, 3.06 BIO]) poltlonwlsc to 8 so]utEGB
]5 of (3aR 4S 68S)-68-(5-bromo- E-Auoro-pheny])-4-(] ]-dEAuoroethv])-3 3a 4 6-tetrahydro-
]1]f-furoI 3„4-cjlsoxRzo]c (304 g, 75',~o pUrliy„647 Inmo]) EB acctlc acid (2 L) 8nd watcT (2
L) 8t 20 C AcTY waITB 'to 40 C RTK1 stn" overnight. DE]utc t]'lc IHlx'tlETc with watcT (2 1,)
and stir vigorously whi]e adding sodium carbonate (4 kg, 43 4 mo]) then adjust to pH 8-9
with further sodium carbonate. Add ethyl acetate (5 L) alld water (2.5 L)„stirfor 30
20 lrllButcs Rrld ]lltcT thTollgh dlRtonlaccous cRrth washing v'1th 2: 1 acctonltrE]c/water.
Separate the ]RycTs, extract thc aqueous with cthy] acetate (2 x 2,5 L) and wash the
combined organic extracts with brine (2 & 2.5 L), dry over magnesium su]fate, fi]ter. and
coBccBtratc to glvc 8 residue. Purify 'thc residue by SFC„co]UBIEI:Chualpak AD-H (5).,
50 x 250 Blnl' chlcDt' ]2 /o ctharloi (0 2 /o dicthv]IBcthy]RIBEIEc EB CO~] flow TRtc 340
25 +~'minute at UV 220 nm to give the title compound as a white sohd (19"..7 g, 84o~o).
[EIjo"' = -6.93 ' (C=0.678, ch]oroform). ES/MS: m/'z ( BT."Br) 354.0/356. 0 [M-', Hj.
WO 2016/176118 PC T/US2016/028896
Preparation 17
I'(2S.3R,4S)-4-Amino-4-(5-bromo-2-Auoro-phenyl)-2-(trityklxymethyi)tetrahydro furan-3-
yl]methanol
O~ OH
2
(trityioxymethyl)-3, 38,4,6-tetrahydrofuro[3, 4-cjisoxazole (31.30 g, 55.9 mlnoi) to acetic
acid (186 lrlL) to glvc 8 suspcnsNln. Add zinc (25.6 g, 391 mlnoi) RBd stll' thc lcactlon
mixture vigorously for 18 hours. Dilute the nlixture v;ith toluene and filter through
diatomaceous earth. Concentrate the tlitrate under reduced pressure. Solubilize the
10 rcslduc with ethyl 8cciatc, vi;ash with brine, Rnd s8tu18icd sodluln bicarbonate. Scparatc
ti'lc ph8scs, dry ovcT lnagllcslum sulfate, flitcT, Rnd concentrate urKicT reduced pTcssur'c to
give the title compound (31.35 g, 99'/o). ES,'MS m/e ( Br/ 'Hr) 562,'564 IM+Hj.
Preparation 18
8-
I I (3S,4R,5S)-3-(5-Hromo-2- fi uoro-phenyl)-4-(hydroxyB'methyl)-5-
(trltyioxymethvi)tetrahydrofuran-3-yi ]carbamothloyi jben7amlde
GH
/ g . s 0
SchclBc 1, step G: Dlssoivc [(2S,3R„4S)-4-amino-4-(5-bromo-2-fluoro-phenyl)-2-
(trityioxymethyi) tetrahydrofuran-3-yl]methanol (31.35 g, 55.73 mmoi) in
20 dlcMOTonlcthRnc (557 mL) Rnd cool io 5 oC. Add benzoyl lsothlocyanatc (9.74 BlL,
WO 2016/176118 PC T/US2016/028896
72A5 BIIBO]). AftCT addi'tloB IS comp]CtC, 8]]OW 'thC TCRctioTi B'BXtUTC to WRTIB to T'OOM
temperature Rnd stlT fol' 2 hoUTs. PouT IBIo saturated sodium hicarhonatc, scparatc thc
phases, Rnd cxtlRci rhc RqUcous phase v'1th dich]oromcihanc. Comhinc thc ol'gaIllc
cxtTact Rncl. div ovcT Blagncsiuln sulf8tc. Pl]tel thc sohltlon Rnd conccntTatc Under
reduced pressure to give the title compound (42.95 g, ]06io). ES/MS ITI/e ('Br/"'Hr)
74//749 I M+Naj.
10
Preparat&OH 19
N-I (48S,5S,78S)-78-(5-HTomo-2-fiuoro-pheny])-5-(1, l-difiuoroethyl)-4, 4a, 5, .'-
tetrahydrofuroI 3,4-dj I 1,3jthiazin-2-yij benzamide
Scheme 2,. step H: Add hcnzov] Isothlocyanatc (].80 B)E,„133 .mino], ) to 8
so]U'tmoB of I (2S,3R„4S)-4-amino-4-(5-hTonio-2-f]uorophcnv])-2-(1, ].-
15 dif]uoroethy])tetrahydrofuran-3-y]jmethano] (4.67 g, 11.9 mmo]) in dich]oromethane (20
mL) Rt Rmhicnt tcnlpcTRturc for 1 hour unti] LCMS shows TcRctlon ls coBlplctc.
EVRpoT'8tC 'thC TCRctioB TMXture to 8 TCslduC UBC1CT VRCUUBI. Add CVciohCXRIIC (50 B'IL),
warm to 60 'C and add methvl tert-butv] ether untl] prec&pltate ls tul]v disso]ved 1 ]00
mL). Filter the hot solution„cool to room temperature and slov ly evaporate under
20 reduced picssuic Untl] folB18tion of 8 white pTcclpltatc. Rclnovc thc solvent Under
reduced pTcssuTc Rnd disso]vc 'thc TcsIduc iTi anhydrous dich]ororncthanc (30 IBL), Rdd
pyTldlBc (2A IBL, 30 mTno]), RBd coo] thc so]ut]on to -25 C. Add
trlf]uoroB1cthancsu]fonic Rnhvdrldc (2.2 B)E 13 Bllno]) di'opwlsc ovcT 30 minutes 8nd
8]]ow to wRTIB 0 C ovcT' 1 hoUT, Crash thc reaction Inlxturc with water (25 rni ), 2 N
23 aqueous hydroch]orle acid (25 mL), water (23 IB]L), aqueous saturated sodIUBI
hicarhonatc (25 mL)„and water ( 5 IBL), di v ovci' Blagncsluin sUlfaic, filter, Rnd
concentrated to dryness. Purify the residue 4y silica gel chromatography e]uting with 5"!4
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Blcthyi /eI E-bu'ty] ether ln dich]GTomcthRnc 'to give thc tlt]c CGIBpound Rs R light. yc]]ow
toam (5 0 g 76 zo 90 '80 pur]tv bv LCMS) & S/MS' BI/z ( Br/ 'Br) 499 0,'&01 0 [M-'Hj
A]teIIIate Preparatln ]9
Scheme 2. step H: Add benzoy] isothiocyanate (98 mL, /24. 9 mmol, ) to a
solutioll of [(2S,3R„4S)-4-8nlino-4-(5-brolno-2-Auoropheny])-2-(1, ]-
dlfluoroethyl)tetrahydrofuran-3-yljmethanoi (197.6 g„546. 7 mmo]) m dlcMoromethane
(].,2 1 ) Rt 30 C for' 1 hour, Add CDl (]0] g, 6].0.4 BBBO1)Rn«1 Stir Rt RnlblCnt
temperature foI' 3 hoUTs. )Further chal gcs of CDl caB bc BIRdc to ensure colnp]ctc
10 consumption of the thiourea intermediate. Heat to 90 "C for 42 hours and cool the
so]Utlon to RIBblcnt tcIBpcT8tul'c. DI]utc thc TcRctlon BllxtUTc Rvlth cthvi Rcctatc (2 L) RIKI.
8«!d 2 N aqueous hy«1TGCMGTlc acid (2 L), stn, 8d«l bTIBc (1 L) RBd scparatc Ihc ]RycI's.
O'ash thc orgalnc layer vi'Ith 2 N aqueous hy«]TGCMorlc acid (0.5 L), bT1Bc (2 & 1 L) Rnd
aqueous saturated sodnUI1 bicarbonate (1 L). Dry over BlagBcslunl sulfate„ 1liter., RB«1
conccntra'tc to glvc 8 Tcslduc, PUTify thc I'cs1«iuc bv sl]icR gci chromatography c]utlng
vvith 0-]00'lo ethyl acetate in iso-hexane to give the title compound as a light ye]klw so]id
(234 g, 83"/o). ES/MS: IB/z ( Br.' Br) 499.0/'501. 0 [M'-Hj.
PTCpRTatlon 20
5-[(4RS,D S,78S)-78-(D-BTOIBO-2-f]uoro-pheny])-5-(trlry]oxyB1ethy])-4, 48,3,7-
tctl ahydroturo[3, 4-d j [1,3jth18zln-2-v] ]bcnzalnldc
Scheme 1. step H: Dissolve N-[[(3S.4R,5S)-3-(5-bromo-2-f]uoro-pheny])-4-
(hydroxyB1cthy])-5-(trlty]oxvBlcthy])tcirahydroturRB-3-yljcarbaBlorilloyljbcnzRBBdc
25 (42.95 g,. 59.18 Bllrlo]) IB dlcMoroiTlethane (591 IBIL) Rn«I. cool to -20 C. Add pylldlne
(12.0 BIL, ]48.0 mmo]). fo]]ov~ed by trif]uoromethanesu] fonic anhydride (]0.97 ml. ,
WO 2016/176118 PC T/US2016/028896
65, 10 BIIBG]). Monitor thc Rddition keeping t]'lc temperature bc]ow -20 C. Stir' thc
TcactloB mixtUTc Rt -20 C foT 30 fninutcs. A]]ovv thc TcRctloB mixture to AvaIIII to Toom
tcmpcraiuic. PGU1 Blto saturated Rmiilon]UIB ch]GI'idc, scpRraic thc phases, Rlld cxtTact thc
aqueous phase Lvlth dich]GTGIBcthanc. Coinbnlc thc GTgaBlc cxti'Rct Rnd dry ovci
magnesiunI su]fate. Fi]ter the so]ution Rnd concentrate under reduced pressure to give the
title comPound (45.24 g, ]08o~o). ES/MS ITIC ("Br,' 'Br), 0,/709 [M-'H].
10
PrcparRUGB 1
N-[(48S.5S,78S)-,8-(5-Bromo-2-f]uoro-pheny])-5-(hydroxymethy])-4, 48,5,7-
tetrahydrofuro[3, 4-dj [1,3]thiazin-2-yi] benzamide
„Q
Scheme 1, step 1: Dissolve N-[(48S„5S„78S)-78-(5-broino-2-Auoro-pheny])-5-
(trity]oxyIBcihy])-4, 48,5,7-tcirahydrof UTG [3,4-dj [],3jthiazin-2-y]]bcnzamidc (45,24 g,
63.93 IBIBG]) ln foTBUC acid (160 IHL) Rnd st]r at RBIb]cnt tcBipcTRtuTc foT 1 houT. Md
15 wvatcr (29 BIL) ovci' R pciiod ol 5 Innlutcs. Stn foT 50 mimltcs. Conccnti'Rtc thc Inixturc
UBdcT reduced pTcssuTc to 8 TcsNluc. Dissolve thc TcsNluc In Incihano] (639 mi), Rdd
triethy]amine (26.7 mi, ]91.8 mmo]). and stn overnight at ambient temperature. Pour
Into brine scpRTatc thc phases Rnd cxtI'Rcr thc RqUcoUs phase Lvith ch]oroforB1. Combine
thc oiganlc cxtTact 8nd dry ovcT BlagBcsiunl suifRtc. Fi]tci' Rnd conccntiatc UndcT reduced
20 pTcssurc to give 8 Tcslduc, PUTify thc I'cslcluc by si]icR gci chTGIBatography, ciutlng wvith
RcctoBc: hcxancs (25-38,~o gradient), to give thc tlt]c conlpouBd (16.04 g, 54 ro). ES/MS
rnle ('Br/ Br) 465/467 [M-'-H].
Preparat! OH 22
(4aS,5S,78S)-2-Benzaniido-78-(5-bromo-2-f]uoro-pheny])-4„48„5, 7-tetrahydio furo [3,4-
d] [],3 ]thiazine-5-carboxy]ic acid
WO 2016/176118 PC T/US2016/028896
Q
HQ~+
Scheme l, step J: Add N-[(4RS, 5S,7RS)-7R-(5-bromo-2-fluoro-phenyl)-5-
(hydroxynlcthyl)-4„4R„3, 7-tctrahydroturo[3, 4-dj [i,3jthlazin-2-yljbcnzarnldc (l 6.04 g,
34.47 mmol) to DMSO (l72 mL). Add 2-iodoxybenzoic acid (35.56 g. l20. 10 mmol)
and stir at ambient tenlperature for 3 hours. Dilute the reaction mixture v ith chloroform
(300 B)E) and pour lrlto satulRtcd alrlmoBIBIB chloTKlc (400 IBL). ScpaTatc thc oTgaBlc
phase and dry ovcT BMgncsluIB sulfRtc, FlltcT thc sohltlon RIKi coBccntra'tc under Tcclucccl
pressure to give a residue. Dissolve the residue in ethyl acetate (400 mL) and v~ash Ivith
saturated Rlrnnolulun chloride (2X250 ITIL). ScpaTatc thc or'gaBlc phase, dry ovcI'
l 0 Inagncslunl sulfate, filter, and conccntrR'tc under reduced pTcssur'c to glvc R Tcslduc,
Dissolve the residue in a dichloromethane: methanol mixture and add diethvl ether until a
solid precipitates. Collect the solid by filtration and dry under reduced pressure to give
thc title colnpound (5 78 g 35 0) ES'WIN mle ( BT' Hr) 479/48l pl+HI
Prcparat! on 23
(4aS„5S, 7RS)-2-8enzalnldo-7R-(5-bromo-2-fIuoro-phenyl)-5-1nethoxy-N-methyl-
4,4a, 5,7-tetrahydrofuro[3„4-dj [i,3jthlazlne-5-carboxamlde
~Q
Q
H
Qi
SchcIBc l, step K: Dlssolvc (4RS,5S,7RS)-2-bcnzamido-7R-(5-bromo-2-fhLoro-
20 phenyl)-4, 4R,5„7-tctrahydrofuro[3, 4-dj [1,3jthiazinc-5-carboxylic acid (5.78 g, l2.l mlrlol)
in dichloromethane (20l mL) and 'A, O-dimethylhydroxylamine hydrochloride ( l.76 g,
l 8, l mmol). Add triethylarrrine (5,29 rBL, 36,2 n'lmol) foHowed by NATU (7.02 g, l 8.l
mmol). Stn at ambient temperature for 3 days. Pour into saturated ammonium chloride,
WO 2016/176118 PC T/US2016/028896
scpaTRtc 'thc phRscs, aild extract thc Rqucous pl'lasc with ethyl acetate. Combine thc
oTgRBic cxtt'Res RBd dry ovcT magnesium sulf8tc. 1'liter RBd coBccntratc under reduced
prcssur'c ro give R I'cslduc. Purify thc residue by silica gcl chromatography, ciuting with
ethyl acctRtc:dlchloToBlctharlc (0-50/o gT8dlcnt) to give thc title compoiuld (4.l 5 g„66io).
ES/MS IEE/e ( Br/ 'Hr) 522/524 [M+Hj.
PI'Cpai'RtniB 24
N-[(48S,5S,78S)-D-Acetyl-78-(5-brolno-2-fluoro-phenyl)-4. 48.5,7-tctrahydrofuTo[3, 4-
dj [l 3]thl R71B-2-vi ]bcn78rm dc
Scheme l, step L: Add dropwise to a -78 'C soiut&on of (48S,5S,78S)-2-
benzamido-78-(5-broEBO-2-fluoro-phenyl)-N-EBethoxy-N-methyl-4, 48,5„7-
tctrahydrofuio[3, 4-dI[l, 3]thiazinc-5-carboxamidc (l.5 l g„2. 89 BUBol) In THP (57.8 mL)
mcthyimagncslum bTomldc (3,0 ETiol/L in diethyl ctl'lcT, 4.8 mL, l4, 5 n'lmol). StiT 'thc
l5 TcactioB 8t -78 ~C foT 5 TMnutcs and Rilow to gradllRlly warIB to ambient tcTBpcTatUTc.
Stir foT 30 nllnutcs. Quciich thc TcRctlon with Encthanol (4 IBL). , dllutc with saturated
ammonium chloride, and extract with ethyl acetate Combme the organic extract and dry
over so(Bum sultRtc. I' !ltcT RBd coBccnti'atc UBdci' reduced prcssure to glvc 8 residue.
Purify thc residue by silica gcl chromatography, clUtiBg wl'th ethyl acciatc: hcxaBcs (0-
20 l00,4 glRdlcnt) to give thc title compound ( L28 g, 93 /0). ES/MS EEI/e ( Bi/ Br) 4! !/479
P,!l-, H],
Preparation 25
N-[(48S,&S,78S)-78-(&-Bromo-2-Auoro-phenyl)-5-( l, l -dIAuoroethyi)-4, 48,5,7-
tetrahydrofuro[3 4-dj[l 3]th]87in-2-vljben7amide
WO 2016/176118 PC T/US2016/028896
Q 0
N N
Scheme 1, step M; Add together dlchloTGIBcthanc (34 mL), bls(2-
Btethoxyethyi)aminosuifur trHluoride (1.52 mL. 6.88 mmoi), and boron trifluoride diethyl
etherate (0.89 BIL, 6.88 mmol). Stir at ambient temperature for 2 hours. Add N-
[(48S„DS,78S)-5-8ccty]-78-(5-broIBG-2-fI uoro-phenyl)-4, 48,5„7-tctrahydrofuro[3, 4-
dj[1.3jthiazin-2-yijbenzamide (0.821 g, 1.72 mmol) in one portion, followed by
triethylamine trilrydrofiuoride (1.13 mL, 6.88 Irunol). Stir at ambient temperature for 18
houl's. Pour lrlto satulatcd RBImoBTUB1 cMorldc, scp81Rtc rhc phases, Rnd cxtl'Rot, thc
aqueous pi'lasc with cti'lyl Rcctatc. Combine thc GTgalnc cx'tTRct Rnd dry over' B18gncsiurn
10 sUifRtc. Filter RBd conccBtratc UndcT reduced pTcssUI'c to glvc 8. Tcslduc. Purify thc
residue by silica gcl chromatography, cluting with dlchlo''GBCcthaB: hcxRncs (80-100 .~o
gradient), to glvc thc tltlc compound (0.552 g„64/i). ES/MS iN/8 (' BT/ BI') 499/501
[M-'l-ij,
Preparation 26
5-[(5S,78S )-5-( 1,1-DIfiuorocthvl)-78-12-fluoro-3-[(trlfiuoroacctyl)RIBIBG Iphcnyi 1-
4R,5„77,8-tctrahydro-411-f UTG [3,4-cij [1,3jthiRzln-2-ylj ben zarnldc
F
s o
Q~FF
Scheme 5, step A: Dissolve N-[(48S,5S,78S)-78-(5-broIIIO-2-fiuorophenyi)-5-
20 (l, l-difiuorocthyi)-48, 5,7,78-tctrahydro-4H-furo[3, 4-dj[1,3jthiazin-2-yljbcnzanlidc (2 4
g, 454,6 BU'Boi) In 1,4-dloxanc (2 L) Rnd Rdd 4 A. BIoiccular slcvcs (37 g), 2, ,2-
WO 2016/176118 PC T/US2016/028896
tH fluoroacctarnldc (9] g, 780,9 Blmoi), flBc]v ground potRsslunl carbonate (114 g, 8 4.9
mmol), sodium iodide (11/ g, 780.6 mmo]), copper (1) iodide (17.5 g, 91.9 mmo]) and
racemic trans-N, N'-dinlethyl-], 2-cyclohexane diamine (20 g, 140.6 mmol) under a
stTcaIB of Bltlogcn. Purge thc vcsscl with 3 vacUUB1 Bltl'ogcn swltcllcs and heat, to 123 C
5 fol' l 8 houTs. Cool to RmbicBI temperature and f!]ter thc so]ut!GH thTough diatolnaccous
caIth, Rnd wash with cthvl Rcctaic. Add satU1Rtcd aqueous RBBBoniunl ch]oridc (2 L) RBd
vigorous]y stll foT 45 Bllmltcs. ScpRT8tc thc 1RvcTs RIKI. vvash thc GI'gRnic ]Rycl' v'1th
saturated aqueous RBBBGBluIB ch]GTidc (3 & 1 L), brlBc ( 300 IBL), dl'v ovcT Inagncsl Urn
su]fate, fi]ter, and evaporate to give a residue. Purify the residue by si]ica ge]
10 chrolnatography c]Utlng with 0-100lo ethyl Rcc'tate ln lso-hcxaBc 'to glvc thc tltlc
compound as 8 light yc]]ow so]Kl (297 9 g 9~ /i 81 ~o pUrlty) ES/MS' IB/z 5~2 0 [M+ 1]I)
PTCparRBOH 7
N-I (48S,5S,78S)-78-(5-ABIino-2-f]uoro-pheny])-5-(], ]-dif]uoroethyl)-4, 4a,5, .'-
tetrahydrofuroI 3,4-dj I 1,3]thiazin-2-y]j benzamide
F
o
Schclnc 1, step N: Combine N-I(4RS„5S,78S)-78-(5-bromo-~-f]Bolo-phcny])-0-
(1,]-dlf]uoroethy])-4, 48,5„. -tetrahydlo]urol 3„4-dlI ].,3 I thlazln-2-v])benzanude (0.372 g,
0, /4 Blmoi) and (]R,2R)-N„N-dirncthy]-], 2-cyc]ohcxancdiaminc (0,037 IHL, 0.22 IIBBG])
20 in ethanol (30 m]). Add sodilml azide (0.194 g, 2.98 mmo]), fol]owed by sodium
ascot'bate (0.66 M so]utlon„0.50 BI]„03.3 Bnrlol). Purge thc top ol thc fl8sk with Bltlogcn
8ncl Rdd cupTic suifRtc (0.33 M so]utlon, 0.68 B'1], 0,22 BIIBG]). Pleat thc Tcac'tloB mlxtuTc
to 80 'C and stir for 5 hours. Coo] the reaction and add co]d water. Extract the mixture
with crhvl Rcctatc. Colrlblnc thc or'galuc extract RIKl dry ovcl' sodium sulfate. Fi]tcr RBd
25 conccntl'Rtc Under reduced pTcssUTc to glvc R residue. Conlblnc thc Tcsiduc with
pa]]adl um (10 IBass",o on cRTbon, 0.35 g, 0, ]6 mlBG]) In cthano] ( 50 ml) RIK1 THF (10 Bll).
Purge the mixture with nitrogen and with hydrogen. Stir at ambient temperature under 50
psi of hydrogen for 1 hour. Filter off the cata]yst and wash with ethyl acetate.
WO 2016/176118 PC T/US2016/028896
CGBccBtratc thc solution UBdcT reduced pTcssuTc to glvc 8 Tcslduc. Purify thc TcsNIUc bv
silica gel chrontatoy aphy, eluting lvith ethyl acetate: dicMoromethane (0-20 so gradient),
ro glvc thc title conlpound (0.2184 g„67, ~o). ES!ASIB/z 436 (M-'-H).
Alternate Preparation 27
Schclnc 5, step 8: Add 7 8 alrmlonia IB BlcthaBG1 (600 mL, 4.2 IBG1) to 8 stirred
sUspcBslon ot 5-[(5S,78S)-5-( I,1-dlfiuorocthyl)-78-12-Auoro-5-
[(trI tiuoroacctyl)anuno j phenyl &I -48,5,7,7a-tcrrahydT0-4H- furo [3„4-dj[1,3j'thl az in-2-
yljbcnzamidc (250 g, 80~/o purity, 3 /6. 3 ]BIBoj)in methanol (200 IBI ) at I OOIII
10 temperature and stir at anlbient tenlperature For 18 hours. Evaporate to dl&ness to give
the title compound as a brown gUln (190 g, 375.2 mmo1„861o purity). ES/MS: nl, 'z 436.0
[M-'Hj.
Preparation 28
(48S DS 78S)-7R-(0-ATAlno-2-Auorophcnyi)-~-(I l-dIAuorocthy])-48, 5,7,7a-tctrahvdro-
4H-furo [3.4-dj [1,3jthiazin-2-arnine
Schcnlc 4. step A: Dissolve N-[(48S,5S,78S)-78-(5-amIBG-2-fluoro-phenyl)-5-
( 1,1-difiuorocthyl)-4, 48,5„7-tctTahvdl'o fuI'o [3,4-dj [1. ,3jthiazin-2-ylj bcnzamidc (216A g,
20 88 lo purity„435.9 lrlnml) In pyrldlne (400 IBL)„ethanol (100 IBL) RIN1 THF (300 lrlL).
Add 0-B'lctl'ly]hydroxyiamlnc hyiirochiorldc (190 g, 2275.0 Inmo]) 8nci s'tlT 8t ambIcnt
temperature fol' l 8 hoUTN J)I]utc with 2-IBcthyltctrahydrofuran (1 I ) 8Bd wash wrth watcT
(2 & 300 mL). Isolate the organic layer and add "50~o aqueous ammonium hydroxide (100
IBL) to thc aqUcous. ExtTact. with 2-Incthyitctrahydroturan (300 mL) then satiillatc vvlth
25 sodulIB chlorulc RIK1 cxtl act with 2-IBcthyltctrahydrofuran ( ~ 300 mL) Cornblnc thc
Gr&anic cxtl'Rcis wash with bTnlc (300 B1L).Rnd cvRpoTatc to 8 Tcslduc. Dlssolvc IB
lrlcthanol (200 IBL),. 8dd 7 N arnIBGBIR ln methanol (100 IBIL, 700 Bllrlol) Rnd stir Rt loolrl
WO 2016/176118 PC T/US2016/028896
temperature foT ].8 houTs, Further 81IB'Bonla cRB bc 8ddc«1 If any trlf]UGTacctaTM«lc
IBlpUTIty I'cIBMBS. Rcmove thc so]vent UndcT reduced pl'cssuTc RBd dlssolvc thc residue ln
8«]ucous 2 N aqueous hydroch]oric acid (1.5 L). Extract with dlcMGTonlcthRnc (6 x 500
mL)„combine thc ol'game 18vcl's RBd Tcnlovc thc solvent Unclcl Tc«iuccd pTcssurc to 8 total
5 vo]lmle of about 1 L. Wash with 2 N aqueous hydrochloric acid (300 mL) and combine
8]]Rqucous wRshnlgs. Add 2-Inethy]tctrahydroiuran (1 L) RB«1 stn vigorously whllc
ad] Ustlng thc pH to basic with so«11UIB blcRrbonRtc Until Bo gRs cvolutlon ls obscl'vc«I. .
ScpaTRtc thc ]aycTs and extract thc aqueous with 2-Incthy]tctrahydrofuran (2 & 500 mi).
DTv thc CGTBblBcd GTgRnic extracts with BIRgncslUIB su] fRtc, fl]tcT, RBd evaporate to g!vc 8
10 brown so]id. Purify the residue by silica gel chromatography eluting with 0-]00"/&
dich]oromcthanc lB THF. Evapolatc thc pl'o«I. uct contMning fTactroBs v'1th cthy]
acetate/heptane to glvc Ihc tlt]c coIBpouBd 8s 8 flBc bclgc powder (]06 g, 70.~0, 95./o
purity). ES/MS: m/z 332.0 [M-.'Hj. [«Ijo
"= +42.11 '"' (C= 0.532, chloroform).
Preparation 29
N-[3-[(4aS,5S,78S)-2-8enzanlido-5-(], 1-dif]uoroethy])-4, 48,5,7-tetrahydrofuro[3, 4-
dj [],3]thIRZIB-78-y]j-4-Auo To-pheny]]-5-cyano-py rid&ne-2-carboxamlde,
SchcIBc 3, Step A: A«1«1 N,N-«lllsopTopylcthvlannnc (0.032 mL„0.1837 Bllrlol) to
20 8 InlxtUrc of 5-[(48s,5s,78s)-78-(D-MBIBG- -f]uoro-pheny])-3-(1, ]-dlf]uorocthy])-4, 48,5, /-
tetrahvdrofuro[3 4-dj [1 3]th&87IB-2-v]jben78BI&de (0 040 g 0 09185 mmo]) 5-
cyaBopyl Idlne-2-carboxy]lc acid (0.0203 g, 0.1378 Bllrlol) Rnd 1-hy dlox v-7-
azabcnzotrlazo]c (0,0191 g, 0.1378 mIBG]) In dIch]oromcthanc (2 m]) RBd
dlmethy]fomIRBI&de (0 5 mL) Add 1-(3-dlmethv]amlnopropv])-3-ethv]carbodnmsde
25 hydroch]oride (0.026 g, 0.1378 mmo]) m one portion. Stir the reaction Inixture at
anlblcnt. tcBlpcl'RttlTc fol' ] 8 houl's. Di]utc 'with cthvl acctatc„RB«I.vvash v'1th watcT and
br]Bc Extract with cthy] 8cctatc, (. Gnlbinc thc GTgMBC cxtrRcts MKj dry ovcT sodium
SU]fMC. Fi]ter RBd COBCCBtTRtC Under TCduCCd pTCSSUTC to glVC 8 residue. Pur! fv thC
WO 2016/176118 PC T/US2016/028896
residue by sihca gel chromatography, elutmg with methyl-/err-butyl ether:
dichkwomethane (0-10'lo gradient), to give the title compound (0.0465 g, 90',~o). ES/MS
m/z 566 (M+1).
~Exam ie 1
N-[3-[(4aS,5S,7aS)-2-Amino-5-( 1,l-difluoroethyl)-4, 4R,5, /-tetrahydro furo [3,4-
dj ~ 1„3jthrazm-7a-yl j-4-fluoro-phenyl j-5-cyano-pvridme-2-carboxarmde
Scheme 3, Step 8; Heat at 50 'C for 18 hours a mixture of N-[3-[(4aS,5S,7RS)-2-
10 benzamido-5-(l, l-difluoroethyl)-4, 4R,5,7-tetrahydrofuro[3, 4-dj[1„3jthiazin-7a-ylj-4-
Auoro-phenyl j-5-cyano-pyrldlnc- -cRrboxRBiKlc (0.0465 g, 0.0822 mmol), 0-
mcthyihydroxylaBUnc hydrochloride (0,0687 g, 0,8220 mrnol) Rnd pyridinc (0.066 B'il,
0.8220 iBiriol) in THF (1.5 iriL) Rnd cthaBol (1.5 IriL). CoBccBti'aic thc Buxturc under
reduced prcssure to give R i'csKI.uc. Pui'ify thc rcsiduc by sillcR gcl cliromatogiaphy„
1 5 cluting w]th 7 N NHS in IBctharlol: dichloromcthanc (0-2~lo gradient), to give thc t]tic
compound (0.026 g, 68'80). ES/MS m/z 462 (M-'1).
20
N-[3-[(4aS,5S,7aS)-2-Amino-5-( 1,1 -di Auoroethyl)-4, 4R,5,7-tetrahydro furo [3,4-
dj [1.3jthiazin-7R-ylj-4-fIuoro-phenyl j-&-cyano-pyr&dine-2-carboxamide 4-
Incthy lbcnzcnc sulk)nate hcirllhydi atc (1:1:0.5)
F
F
QH
Q =- S.=- Q
WO 2016/176118 PC T/US2016/028896
]0
Add N-[3-[(48S,5S,78S)-2-8IBIIE0-5-(]„]-dit]UGTocthy])-4„48„73-,
tetrahydrofuro[3, 4-dj [],3jthlazln-78-y]j-4-f]uom-pheny]j-5-cyano-pyrldlne-2-
carboxaIH1dc ( ]50 Blg, 0.33 Bnnol) and THF (2 IYEL) rogcrhcT Rn«l silT at I'Oonl tcnlpcratUlc
to disso]vc. Add p-to]ucncsu]follic acid hydrate (0.095 g„0. 5 BUBO]) RIKI. heat thc so]ution
to 50 'C. Add voter in 200 microhter ahquots and observe precipitation after about 2 mL
totR] addition. Stll at 50 OC fol' scvclR] hours to give 8 thick suspcnsloB. Add Rd«ll'tional
THF (l irlL) to lBlprovc Inixlng. Cool to TGGB1 tclnpcraturc ovcT 8 fcvv hoELrs and fi]tcl' by
vacUUBI filtration. LtI 8sh Yvlth B'BBIIBR]THF. AHGYv to RIT «lrv ovcTnlg]'lt to give thc title
ConlPOTIB«].
AltcTBatc Tc Riatlon Exanl lc la.
N-[3-[(4aS,5S,7aS)-2-Amino-5-( l, l -di fluoroethy])-4, 48,5,7-tetrahydro furo[3, 4-
dj[],3jthiazin-7a-y]j-4-f]uolo-phcily]]-5-cyano-pyridinc-2-carboxamidc 4-
Incthy]bcnzcllcsu]fonatc hcirnhydi ate (l:]:0.5)
Add N-[3-[(48S,5S„78S)-2-arrrin0-5-(],]-dif]uoroethy])-4, 48,5,7-
tetrahvdmfuro[3 4-dj[l 3jth]87IB-78-y]j-4-f]uoro-pheny]j-~-cyano-pvrldlne- Ecarboxamide
(].5 g, ".3 minol) aild THF (]2 mL) together and stir at room tenlperature to
«lissolvc. Heat to 60 '"C RBd add Ji-to]uciicsu]fomc acKI. hydiatc (0.75 g, 3.96 IBBlol) and
water (5 B'EL). A wvhIEc pr'cclpltatc forms RftcT 5 TMBUEcs of Stirring, SUT at 60 C for
20 scvci'al holus to glvc 8 thick sUspcntloB. Cool ro Toom tcIYEpcrarurc over' 8 fcvv hoUls and
filter by vacumn fi]tration. A]]ovv to air dry overmght to give the tit]e compound.
x-Rav Pmvder DlffractKIB (xM3)
The XM3 patterils of crysta]]iEIC so]ids are obtained on a Bruker D4 Endeavor X-
25 ray powder dlffractometer, equipped &vlth a CUKR source i. .-- ].54060 A) and a Vantec
detector, opcTatitlg at 35 kV RB«l 50 mA, Thc samp]c ls scRBBcd between 4 RBd 40' itl 20,
Avith 8 s'tcp slzc of 0.009 in 20 Rnd R scRB IRtc of 0.5 sccoBds/s'tcp, RIKl &vith 0.6 IBB1
«livclgcncc, 5.28 flxcd anti-scattcl', alld 9.5 irln1 detector slits. Thc dry povvdcT Es pRckcd
GB 8 quartz sarnplc ho]dcl Rnd R sinoot]'1 sUI fRcc ls obtalllcd usiBg 8 g]Rss s]ldc, Thc
30 clysta] form dlf&actlon patterns are co]]ected at ambient temperature and relatrve
huniidity. lt ls vvc]] kBovA1 Bl thc crys'tallograpl'lv art that, foI' Rny glvcB crvsrR] form„thc
Tcl8tivc lntcnsltics of thc diffTactlon peaks TE18v vary duc to pTcfcrrcd GTlcntRtloB Tcsu]ting
from fRctoTs suc]'1 as CTysta] IBGTphologv and habit. XVhcrc the cffccts of prcfcrTcd
WO 2016/176118 PC T/US2016/028896
OTICntation RI'C pr'CSCBI, pCRk UltCBS1'tlCS RTC 8]tered, bent t]'lC ChRTRCtCTIStiC pCRk posl'tloBS Of
the po]ymoq&h are unchanged. See, e.g. , The United States Pharmacopeia 423, Nationa]
Formulary +r'-]8 pages l 843-]844 ]995 Furthermore it is also weH known in the
clystaHQQT8phy 81t that foT Rny given cl vsta] foITB thc arlgular pc8k positlorls may vary
5 shght]y. For example. peak positions can shift due to a variation in the temperature or
hulrudity at which R sarnplc ls analyzed, sairlplc disp]accmcnt, or 'thc pI'cscBcc or absence
of RB intclnR] standard. En thc plcscBt case„Rpeak position vRriablhty of '+ 0.2 ln 20 wiH
take Into Recount these potcnti8] vRTIRtions wl'thout hiBdcriBg thc Encqulvoca]
identification of the indicated crystal form. Confirmation of a crysta] form may be made
]0 based oB RBv umquc coB1binaiion of dis'tlnguishlng peaks (Ul Blurs of ' 20), typicaHy thc
BWI'C pl'ODUBCrlt pCRkS. ThC CryStal folnl diffraction pattCIBS, COHCCtCd at anlblCnt
temperature and re]atlve hlmlidity, are adjusted based on NfST 675 standard peaks at
8.853 and 26.774 '"'2-theta.
A pl'cpRTcd samp]c of crystR]hnc A-[3-[(48S,DS„78S)-2-81Tllno-D-(],]-
dl f]uoTocth vl)-4, 48,5,7-tcrrahydTo fuTo [3,4-dj [l.3jthl Rzln-78-y]]-4-]] uoro-phcny]]-5-
cyano-pyrldlnc-2-calboxamidc 4-mcthy]bcnzcncsu]fonatc hcmlhydratc (l:l:0.5) ]s
chRTRctcrlzcd by RB X&3pattcrB usn1g CUKR radiation Rs havnlg diffraction peaks (2-
thctR vR]ucs) Rs dcscribcd ln Tab]c l, Rnd in partlcu]RI' having peaks Rt 6.8 in
COB1binatlon With OBC OT IBOTC Ot thC pCRks SC]CC'tCC] fTOM thC group Consisting Of ] 9,7
20 ]4.9'"', and ]0.3"'; with a tolerance for the diffraction angles of 0.2 degrees.
WO 2016/176118 PC T/US2016/028896
Table 1:X-ray powvder diffraction peaks of the crysta]line Example la
Exam lc 18 Peak Poslrlons
Ang]C ( -Theta) + /-
0.2"
Re]ative lntCBSltv
(A~ of most IBtcBsc cRk
12.5"ro
100.0"~o
17,2"io
] 8.7".o
21.0
4.8'
8, ]'./o
5.1"/o
I~ixam 1e 1b
N-i 3-[(4as,5S,78S)-2-Amino-5-( 1,1-diiiuo Toethy])-4, 48,5„7-tetrahydro furo [3,4-
dj [1,3jthlazin-7a-y]j-4-f]uoTo-phcnylj-5-cyano-pyrldinc-2-carboxalnldc Inc'thancsulfonRtc
0.= S.=.0
0H
Add N-[3-[(4RS,5S,788)-2-amino-5-(] „l-dif]uorocthy])-4„48„57,-
tctl Rhvdl o]ul 0[3,4-d j [1,3]th18zln-7R-vi )-4-f]uo To-phcBylj-5-cyarlo-pvl ldlnc-2-
10 carboxalnldc (]50 BIg, 0.33 mmo]) RBci TFf]F (2 IB1 ) together Rnd stir 8t Toonl temperature
to dissolve. Add methanesu]fonic acid (0.095 g, 0.5 mmo]) and heat the so]ution to 50
'C. Add v;atcr ln 200 IBEcro]Etcr 8]IEjuots up to 2 mL total Rddltlon. Stir Rt, 25 'C RIld
pTcclpl'tRtlon 1$ Hot observed, Conccntra'tc under Introgcn to ~/~ vo]umc Rnd 8 prccipltatc is
observed. Heat the suspension to 60 'C and a c]ear solution is observed after about 10
15 BBButcs. Hear Rt 60 oC fol' 1 hour. Cool 'to I'ooln tcnlpcraturc to gEvc 8 %kite suspcBslon
and stir the Inixture for several hours. Ilso]ate the so]id by vacuum filtration and wash
'tvlth 8 GUHBBR] RITEount, ot vvatcr. A]]ow to RIT dry ovcrtnght, to glvc thc tl'tlc colTEpounci 8s
WO 2016/176118 PC T/US2016/028896
a crystaHine solid.
Ii 1 vliro AssR Procedures:
To Rsscss sclcctlvltv of BACEl ovcT BACE'~ thc t~st compouIKI. Is cvRhlRtcd lB
FRE 1 8TKl Imlnunoassay detection bRsc cnzylBatlc RssRys UslBg spcclflc substratcs foT
BACE1 RIK1 BACE2 Rs described below. For' iEE vi iE'0 cBzylrlRtlc Rnd cellular Rssays„ thc
test coBlpouncl. ls pl'cpaTcd IB DMSO to Inakc lip 8. 10 nlM stock solutloB. Thc stock
solu'tloB is scTlRHv dliU'tcd iB DMSO lo ob'tarn 8 tcB-poln't dilution clirvc with hnai
coEIIpound conccBtratlons Tang]ng fl'GIB 10 IIM to 0.05 BM IB 8 96-wcH Tound-bottom
10 plate bcfoI'c conductlBg tl'lc EEI vEEE'0 cnzyrnRtlc RIK1 whole cell RssRys.
Explcsslon of /EEEBACE1:Fc Rnd AEEBACE:Pc.
Hulnan BACE1 (RccCSSNIB number: AF1 90723) RIN1 hllBIRB BACE2 (8ccCSSIOB
nunlber: AF 204944) are cloned fmm total brain eDNA by RT-PCR. The nucleotide
sequences corresponding to 8B'uno acid sequences Ni to 460 Rrc Inserted into thc cDNA
encoding hunlan ig61 (Fc) polypeptide (Vassar et Rl., SeieEEee„286,735-742 (1999)).
This fusNln pmtem of BACH 1 (l -460) or BACE2(l -460) and human Fc named
AEEBACE1;Pc Rnd IEEEBACE2:Fc Tcspcctlvclv, RTc constructed rtl tl'lc pJB02 vcctoT,
20 Human BACE1(1-460):Fc(AEEHACE1:Fc) arid hunlan HACE2(1-460):Fc (AEEHACE2:Fc)
are transiently expressed in HEK293 cells. cDNA (250 pg) of each construct are Inixed
with FUgcnc 6 and added to 1 lltcT HEK293 ccHs. Four days RftcT thc traBsfcctloB,
conditioned IBcdla RTc harvcstcd foT purification. /IEEBACE1:Fc RBd IEEEBACE2:Fc arc
puTiflcd by PTotciB A chTGB18tographv Rs described bc]ow. Thc cBzylncs RTc stored Rt.—
25 80 ~C ln smRll Rhquots. (Scc Yang, e/. EEI..J. &VeEEEoe/EeEIEEst@'. 9I(6) 1249-59 ( 004).
PUTItlcatlon of IEEEBACEl:Pc Rnd /IEEBACE2:Fc.
Condltloncd media of HEK293 cells transiently 'trRBsfcctcd with IEEEBACEl 'Fc GT
AEEBACE2:Fc cDNA are coHected. Cell debris is removed by tlltering the conditioned
30 media 'thl'GUgh 0.22 pm stcI'llc fllrcT. 5 nil PI'otclB A-RgRI'osc (bcd vohlmc) ls added to 4
]Itcr condltloncd EIIcdla. . This rmxtUTc ls gently st]rrcd ovcrmght at 4 C. 1hc PI'otclB Aagarose
resm is collected and packed into a lov -pressure chromatography column. The
WO 2016/176118 PC T/US2016/028896
co]ulnn ls washed with '.. 0x bcd vojulncs 0fPBS Rt 8 fjow Tate 20 Ini pcl hour Bol«nd
/luBACE j:Fcor IluBACE2:Fc protein is e]uted with 50 mM acetic acid, pH 3.6, at flow
rate 20 ml per hour. 1 nlj fractions of eluent Rre BeutraHzed immediately with alnmonium
acetate (0.5 ml 200 mM), pH 6.5. The purity ot final product ls assessed by
electrophoresis in 4-200/0 Tris-G]ycine SOS-PAGE. The enzyme is stored at —80 'C in
smaH ajiquots.
BACF] FRF'T Assa
ScBR] dl]tltlons of thc Test coBLpouBd RI'c prepared Rs described Rbovc. Thc
10 compound is further diluted 20x in KH2PO4 buffer. 10 )LL of eacjl dilution ls added to
CRCh vvCH On TOW A to H Of R ColTespondlng ]OW protCln blndlng MRCk p]atC Contalnnlg
the reaction mixture (25 UL of 50 mM KH;PO4, pH 4.6, ] mM YRTTON X-100, 1
Blg,'IBL BSA, Rn«l 15 )AT of FRET sUbstTatc based Upon thc scqucncc of APP) (Scc Yang,
e/. Ql. , J. LeuI ocAeIIIisk'I;v„9I(6) 1249-59 (2004)). Thc content. ls Bllxc«1 wc]1 on 8, p]atc
ShRkCT foT 10 IBUlutes. 15 )LL OT 200 pM huIBRB BACE1(1-460):FC(SCC Vasser, e/ aI, ,
Science, 286, 735-/41 (1999))in the KH2PO4 buffer is added to the p]ate containing
substrate Rncl thc test colnpouBd ro 1Bltiatc thc lcactlon. Thc KFU of thc Buxturc Rt tBBc 0
ls recorded Rt excltatlon wavelength 3y3 BIB Rn«1 cmlssloB wavelength 460 Bm~ 8ftcT bTlct
IIBxlng on 8 plate shRkcT, Thc TcactioB plate 1$ covcTcd wit]'1 R]UIBirnlm foI] RIK1 kept ln 8
20 dark hulnidified oven at room temperature for 16 to 24 hours. The RFU at the end of
lnCubatlon IS TCCOT«ICd VVlth thC SRBIC CXCltRtloB RBd CB11SSlon Settings USCd Rt tBBC 0. ThC
difference of the RFU at time 0 and the end of Incubation ls representative of the actrvlty
of BACE1 under the compo«md treatment. RFU differences are plotted versus inhibitor
concentration and a curve is fitted v ith a four-parameter logistic equation to obtain the
25 TCso va]ue. (May,. e/ aL„J.ouI IM/ ofNeurosoienoe, 3I, 16507-16516(2011)).
Thc compound oj Exarnplc ] ls tcstc«1 csscntla]jy Rs dcscTibcd Rbovc and exhlblts
an TCsa for BACE1 of 0.509 nM + 0.104, n= 4 (Mean + standard deviation of the mean).
This data dcIBoBstlatcs that thc conlpouncl. Qf Example 1 lnjllblts pullflc«I. I'ccomblnaBt,
BACE] cnzvIBc actlvlty M vltFo.
WO 2016/176118 PC T/US2016/028896
BACE2gv18P-C125Sv~e Assay
10 point serial dilutions of test compounds are prepared in the appropriate range.
CompouIKls aic fEuthcr di]utcd 6~ ln RIBBIGBIUBI acctatc Rssay bUffcT (50 mlnol
5 ammonium acetate, pH 4.6, 1 mM Triton X-100, ] mg/mL BSA). ]0 pL of each dilution
ls a«ldcd to each wcH on low A to H of 8 corrcspollding ]ow protcnl bnl«lnlg plRtc to
which 10 UL of an affinity purlhed I'sdlerlcIEIa co/I derived substrate (MBPC125swe„ 1
ug/rBL) for BACE2 activity are pre-added, The content ls mixed weH on a p]ate shaker
for 10 minutes. 10 pL of 200 picomolar human BACE2 (1-460):Fcin the same reaction
10 buAcr described Rbovc Es Rddcd to thc plate colltalnlBg substTatc and test coIBpounds 'to
lBltlatc thc Tcactloll. AftcT 4 houTs, thc I'cactloB 1$ stoppc«l by R«kllng stop buffcl' (40 UL).
The amount of product is measured by ELlSA using MBP-C26swe standard. Anti-MBP
antibody is immobilized on the surface Gf a, high binding polystyrene plate and blocked
usllig 8 casclB/PBS blocking buffci. SRBlplc GT standRE'd (40 ]EL) ls added to thc EL1SA
p]8tc RBd EBcubatcd R't 4 C ovcrrnght. T]'lc p]R'tcs RTc then WRshcd Rnd 40 IiEL of thc
c]eavage specific detection antibody (GN405) is added and aHowed to sit for one hour at
roonl icnlpcI'atui'c. UBboulid CYN405 ls il'icn removed by washiBg RBd 40 1EL of goat Rntirabbit-
llRP conjugate (Southern Biotech„4010-05)ls added to the plate and aHowed to sit
foT ] houT 8t Toom temperature. Thc plate ls Rgaln washed RBd TMB sUbstratc (40 ]EL) ls
20 added. Tl'ic CGIYcspoB«lnlg RITEGUBt of product Tclcascd Es R IBcasllrc of BACE2 activity En
thc solution Rt. Rny tcstcd conccntl'RtnlB of inhlbltol. Thc 10-point EBhlbltion cUI'vc ls
plottc«1 RB«1 fitted with thc tour-parameter logistic c«juR'tloB to obtain thc ECg«& Rnd lCqo
va]ues. (See: Sinha, et al. , iV«EtuE e, 402, 53:-540 (2000)).
Thc conlpouIKl of ExaIBplc 1 1$ tcstc«l csscnilaHy as dcscI'Ebcd above and exhibits
25 8 BACE2 1C5o of 17.6 BM -l- 7.4, n'==-6 (McRn + standard «lcviation of thc Incan)„ ihc Tatlo
of BACE1 (FRET 1C5O enzyme assay) to BACE2 (MBP-C125Swe ceH assay) is
approxinlatclv 35-fo]d, indicating functEGBR1 sc]ectivity for' inhibitilig 'thc BACE1
cnzyBlc. Thc «1Rta sct forth above «lcmoBstE'ates that thc colnpotuid of ExaBlplc 1 is
SC]CCtlvC foT HACE1 OvCT HACE2.
WO 2016/176118 PC T/US2016/028896
SH-SY5YAPP695% t 'A'ho]e CCH Assa ~
fhc TGUtlnc who]c cc]l ass8y foT thc mcasul'cB lent of ]nhlbltlon of 8ACE1 activity
Uii]izcs thc hun18Il nculob]astoma cell 1Enc SH-SY5Y (ATCC AcccssEOB NG. CRL2266)
stably cxpTcsslng 8 huIBRB APP693%t cDNA. Ccl]s RTc TGEEtlnciy Used Up to passage
5 number 6 and then discarded.
SH-SY5YAPP695%t cells are plated m 96 we]] tissue culture plates at &.0x]0
ce]ls/we]1 in 200 pL cu]ture media (50',~o MEM/E8SS and Ham's F12, ]x each sodlurn
pvTuvatc, BGB-csscntlR] Rlnlno Rclcls Rnd NRHCO3 CGB181nlng ] 0/o F8S) Thc fo]lowing
day, media is removed from the ce]ls, fresh media added then incubated at 37 'C for 24
10 hours in the presence/absence Gf test compound at the desired concentration range.
At thc cnd 0( thc EIEcubatlon, condltloncd nlcdla RTc 8BR]yzccl. (Gr cvldcBcc of bctRsecretase
activity by analysis of Abeta peptides 1-40 and 1-42 by specific sandwich
EL1SAs. To nlcaslrrc il'lcsc spcclflc isoforms of Abcta, lnonocional 263 Es Used as 8
capture antibody for Abeta 1-40 and nmnoclonal 21F12 as a capture antibody for Abeta
1-42, 80(]'1 Abcta ]-40 RBd Abcta 1-42 EL](SAs Usc bio'tlBy]8tcd 3D6 Rs 'thc reporting
REItibody (foT dcscl'lptloB of antibodies, scc 30]IBson-Vvood, e/ QI., Proc. .vQfL ACQd. SQE.
USA 94, ]550-]555 (1997)). The conccntrRtloB of Abcta r'clcRscd ln 'ihc conditioned
Incdra fo]lowing thc compound trcatnlcnt corrcspoIKls to thc Rctlvlty of 8ACE1 Under
sUch condltlons, Thc 10-poltlt. EnhlbltEGIE curve ls p]ottcd Rnd fitted with thc touT-
20 parameter loglsilc cqURtloB Eo obtain thc 1C5avalUcs fol thc Abcia-lowering cffcct.
Thc colnpound of Exalrlplc 1 ls tested csscntlR]]y Rs described above RBd cxhlblts
an 1C&E, of 0.157BM + 0.048, n=-4 for SH-SY5YAPP695Wt A-beta (]-40) EL1SA and arl
(C58 of 0.1;7BM+ 0.050, n=4 for SH-SY5YAPP695%t A-beta (1-42) EL(SA (IMean +
stalldard deviation of the meall). The data set forth above demonstrates that ihe
25 compound of Examp]c 1 lnlllblts 8ACE] En thc whole cell 8ssay.
1EE vlvo ]EEhibition of 8cER-Scclctasc
Scvclai RBEEBR] nlodc]s, Enc]udlng ITEGUsc, giillncR pig, dog„and monkey„nlay bc
Used to scTccB foT EIEhlbEIEGB of beta-sccTctRsc Rctlvltv Pl vlvQ fo]]owEIEg colnpouBd
80 t!catmcBt Anima]s Used ln this lnvcntloB can bc wlM tvpc transgcmc 01 gcnc knockout
RBlITER]s. For cxanlplc, thc PDAPP lnousc EIlodcl, prepared Rs described in GREncs E'.E QL,
AQEED'e 373, 523-527 ( 1995), Rnd other BOB-tTRBsgcBEc GT gcnc knockout anima]s arc
WO 2016/176118 PC T/US2016/028896
useful to analyze in vi vo inhibition of Abeta and sAPPbeta production in the presence of
inhibitory compounds. GCBCTRHy, 2 month old PDAPP mice, gene lmockout mice or nontransgemc
aninlals are administered compound formulated in vehicles, such as corn oil,
beta-cyclodextran. phosphate buffers PHARMASOLVE' or other suitable vehicles via
5 0I'8l, subcutaBcotls, intra-venous, feeding, 0T othcT Tonic of adEIEiBistration. l to 24 hotlTs
followiilg the administratioil of conlpoun«L animals are sacrificed, and brams are removed
loE Rnalysls of Abcta l-x. "Abcta l-x" 8$ usc«I. hcrcln Tclcrs to thc sunl ol Abcta spcclcs
that begm with residue l and end with a C-terinlnus greater than residue 28, This detects
the majority of Abeta species and is OACB called "total Abeta". Total Abeta peptides
l0 (Abeta l-x) levels are measured by a sandwich ELlSA, usmg Enonoclonal 266 as a
capture alltlbody Rnd biotlnylatcd 3D6 as Tcpolting antlbocly. (Scc May„e/ a/. , Joili'1%Ii oi
Veilroseienee, 34. l 6507-l65 l 6 (20l l)).
For Rcurc srudlcs, compolul«l 0T appropriate vchEclc Es RdnBBistcrc«l and animals
arc sacrificed at 8bout 3 houTs Rftci' dosing. BTREB tlssuc„ ls ObtRlncd fT0BI sclcctc«l
RIHIBals RB«l RBRlyzcd toT Ehc pTcscncc of Abcta l-x, AftcT chT0IHC doslBg bTREB tissues of
older APP transgcnlc RBUBals IBRy also bc RB8lyzcd foT thc amount of beta-amylold
plaques following compound treatment.
Animals (PDAPP 0T othcT APP traIEsgcrnc 0T Bon-tTRBsgcnlc n'Hcc) 8«lIBEIHstcTcd
8B inhibitory compound Inay dcIBonstratc thc Tc«luctlon of Abc'tR ln braEIE tissues, 8$
20 compared with vehicle-treated controls or time zero controls. For example, a 0.l, 0.3, and
l mg/kg oral dose of Example l „ to young female Pl3APP mice reduced Abeta l-x
pcptldc lcvcls Ul bTREB hippocampus by 32 I o, 40/o„and 55~lo (RH values p & 0,0l),
Tcspcctivcly. In brain cortlcRl tissue, «Ioscs of O. l, 0.3, an«!. l nig/kg of ExaB Epic l reduced
Abeta l-x levels by 38".~o, 50"/o, and 6"/o (ail values p - 0.0l) compared to vehicle-treated
25 mice thi'cc hours Rftci dosing.
Glvcil thc ac'tlvltv of thc coIBpoulld of Exarnplc l RgaiBst thc BACEl cnzvIBc iII
vitro, these Abeta- lowering effects are consistent v.ith BACEl inhibition ill vivo, and
further demonstrate CNS pcBcti'RtnlB of thc compound of Example l.
These studies show that compounds of the present invention inhibit BACEl and
30 are, therefore, useful in reducing Abeta levels.

WE CLAIM:
1. A compound of the formula:
,
or a pharmaceutically acceptable salt thereof.
2. The compound or salt thereof according to claim 1 wherein the compound is:
.
3. The compound or salt thereof according to either one of claims 1 or 2 wherein
the compound is:
.
- 55 -
4. The salt according to claim 3 which is:
.
5. The salt according to claim 3 which is:
0.5 H2O
.
6. The salt according to claim 3 which is:
.
7. The compound or salt thereof according to any one of claims 1 to 3 wherein
the compound is N-[3-[(4aS,5S,7aS)-2-amino-5-(1,1-difluoroethyl)-4,4a,5,7-
tetrahydrofuro[3,4-d][1,3]thiazin-7a-yl]-4-fluoro-phenyl]-5-cyano-pyridine-2-
carboxamide.
8. The compound according to claim 3 which is N-[3-[(4aS,5S,7aS)-2-amino-5-
(1,1-difluoroethyl)-4,4a,5,7-tetrahydrofuro[3,4-d][1,3]thiazin-7a-yl]-4-fluorophenyl]-
5-cyano-pyridine-2-