FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION (See section 10, rule 13)
“DISUBSTITUTED PHTHALAZINE HEDGEHOG PATHWAY
ANTAGONISTS”
ELI LILLY AND COMPANY, a corporation of the
State of Indiana, United States of America of Lilly
Corporate Center, Indianapolis, Indiana 46285, United
States of America
The following specification particularly describes the invention and the manner in which it is to be performed.

DISUBST1TUTBD PHTHALAZINE HEDGEHOG PATHWAY ANTAGONISTS
The present invention relates to Hedgehog pathway antagonists and, more specifically, to Hovel disuhstituted phthalazines and therapeutic use thereof. The Hedgehog (Hh) signaling pathway plays art important role in embryonic pattern formation and adult tissue maintenance by directing cell differentiation and proliferation. The Hedgehog (Hh) protein family, which includes Sonic Hedgehog (Shh), Indian Hedgehog (Ihh), and Desert Hedgehog (Dhh) are secreted glycoproteins that undergo post-tra.oslatio.nal modifications, including autocatalytic cleavage and coupling of cholesterol to the ammo-terminal peptide to form the fragment, that possesses signaling activity. Hh binds to the twelve-pass transmembrane protein Ptch (Ptclil and Pteh2), thereby alleviating Ptch-mediated suppression of Sraoothened (Smo). Smo activation triggers a series of intracellular events culminating in the stabilization of the Gli transcription factors (GliL Gli2,, and GIB) and the expression of Gil-dependent genes that are responsible for cell proliferation, cell survival, angiogenesis and invasion.
Hh signaling has recently attracted considerable interest based on the discovery that aberrant, activation of Shh signaling leads to the formation of various tumors, e.g., pancreatic cancer, meduMoblastoma, basal cell carcinoma, small ceil lung cancer, and prostate cancer. Several Hh antagonists have been reported in the art, such as the steroidal alkaloid compound IP-609; the aiainoproline compound CUR61.414; and the 2,4-disubstitoted thiazole compound JK 1.8. WO2005033288 discloses certain 1,4-disubstituted phthalazine compounds asserted to be hedgehog antagonists.
There still exists a need for potent "hedgehog pathway inhibitors, particularly those having desirable pharmacodynamic, pharmacokinetic and. toxicology profiles. The present invention provides novel .1,4-di substituted phtbalazines that are potent antagonists of this pathway.
The present invention provides a compound of Formula 1:


Formula I wherein:
Rl is hydrogen, fluoro, cyano, trifluoromethyl, methoxy or trifluoromethoxy;
R' is hydrogen or methyl; and
R\ R4, R", R6 and R are independently hydrogen, chloro, fluoro, cyano, trifluoromethyl or triOuaromethoxy, provided that at least two of R\ R4, R\ R.h and R' are hydrogen; or a pharmaeeuticaJly acceptable salt thereof.
It will be understood by the skilled artisan that the compounds of the present invention comprise a tertiary amine moiety and are capable of reaction with a number of inorganic and organic acids to form pharmaceuticaliy acceptable acid addition salts. Such pharmaceuticaliy acceptable acid addition salts and common methodology for preparing them are well known in the art. See, e.g., P, Stahl, el«/., HANDBOOK OF PHARMACEUTICAL SALTS: PROPERTIES, SELECTION AND USE, (VCHA/Witey-VCH, 2002); S.M. Berge, el al.y "Pharmaceutical Salts, "'Journal ofPharmaceutical Sciences^ Vol 66, No. 1, January 1977.
Specific embodiments of the invention include a compound of Formula I, or a pharmaceuticaliy acceptable salt thereof wherein:
(a) R! is hydrogen;
(b) Rf is fluoro;
(c) R2 is hydrogen;
(d) R^ is methyl;
(e) R* is chloro, fluoro, trifluoromethyl, or trifluoromethoxy;
(f) R' is fluoro, trifluoromethoxy, or trifluoromethyl;
(g) R! is hydrogen, and R': is hydrogen; (h) Rf is fluoro, and R2 is hydrogen; (i) R* is hydrogen, and R* is methyl; (j) Rs is fluoro and R? is methyl;
(k) R! is hydrogen and R'' is chloro, fluoro, trifluoromethyl, or
trifluoromethoxy;
(!) R! is fluoro and R:' is chloro, fluoro, trifluoromethyl, or trifluoromethoxy;

(m) R" is hydrogen and R* is chloro, fluoro, trifliroromethyl, or
trifluoromethoxy;
(n) R" is methyl and R' is chloro, fluoro, frifluoromethyl or trifluoromethoxy;
(o) R1 is hydrogen and Rs is fluoro, trifluoromethoxy, or trifluoromethyl;
(p) R is fluoro and R" is fluoro, trifluoromethoxy, or trifluoromethyl;
(q) R": is hydrogen and R" is fluoro, trifluorornethoxy, or trifHiorornefhyl;
(r) R~ is methyl and R" is fluoro, trifluoromethoxy, or trifluoromethyl;
(s) RJ is chloro, fluoro, trifluoromethyl or trifluoromethoxy and R' is fluoro,
trifluoromethoxy, or trifluot'omethyl;
ft) R! is hydrogen, R": is hydrogen, and R;1 is chloro, fluoro, trifluoromethyl, or
trifluoromethoxy;
(u) R! is hydrogen, R~ is methyl, and R'"' is chloro, fluoro, trifluoromethyl, or
trifluoromethoxy;
(v) R! is fluoro, R2 is hydrogen, and R' is chloro, fluoro, trifluoromethyl, or
trifl uoromethoxy;
(w) R1 is fluoro, R" is methyl, and R'! is chloro, fluoro, trifluoromethyl, or
trifluoromethoxy;
(x) R.! is hydrogen., R" is hydrogen, and RJ is fluoro, trifluoromethyl, or
trifluoromethoxy;
(y) Rf is hydrogen, R" is methyl, and R" is fluoro, trifluoromethyl, or
trifluoromethoxy;
(z) R.! is fluoro, R*1 is hydrogen, and .R" is fluoro, trifluoromethyl. or
trifluoromethoxy;
(aa) R* is fluoro, R": is methyl, and R" is fluoro, trifluoromethyl, or
trifluoromethoxy;
(bb) R is hydrogen, K" is hydrogen, R' is chloro, fluoro, trifluoromethyl, or
trifluoromethoxy and R" is fluoro, trifluoromethyl, or trifluoromethoxy;
(ee) R: is hydrogen, R3 is methyl, R' is chloro, fluoro, trifluoromethyi, or
trifluoromethoxy, and R5 is fluoro, trifluoromethyl, or trifluoromethoxy;
(dd) Rl is fluoro, R2 is hydrogen, R' is chloro, fluoro, trifluoromethyl, or
trifluoromethoxy, and R" is fluoro, trifluoromethyl, or trifluoromethoxy;

(ee) R! is fluoro, R" is methyl, RJ is chloro, fluoro, trifluoromethyl, or
ftifluoromethoxy, andR' is fluoro, tnfluororaethyl, or tritluoromethoxy;
(ff) R! is hydrogen, R; is hydrogen, R' is triffuoromerhyl, and. R" is fluoro;
(gg) R! is fluoro, R" is hydrogen, RJ is trifluoromethyl, and R3 is fluoro;
(hh) R is hydrogen, R" is methyl, R'! is trifluorornethyi, and R" is fluoro;
(ii) R! is fluoro, R" is methyl, R'* is trifluoromethyl., and R' is fluoro;
(jj) three of R*', R4, Rv, R" and R are hydrogen; and
(kk) four of R'\ R\ Rs, R" and R' are hydrogen. The present invention also provides a pharmaceutical composition comprising a compound of Formula 1, or a pharmaceutical!)' acceptable salt, thereof in combination with a pharmaceutically acceptable excipient, carrier or diluent.
The compounds of the present invention are preferably formulated as pharmaceutical compositions administered by a 'variety of routes. Preferably, such compositions are for oral or intravenous administration. Such pharmaceutical compositions and processes for preparing them are well known in the art. See, e.g., REMINGTON: THE SCIENCE AND PRACTICE OF PHARMACY (A. Gennaro, et al, eds,, 19ih ed„ Mack Publishing Co., 1995).
The present invention also provides a method of treating medulioblastoma, basal ceil carcinoma, esophagus cancer, gastric cancer, pancreatic cancer, biliary tract cancer, prostate cancer, breast cancer, small ceil lung cancer, non-small cell lung cancer, B-eell lymphoma, multiple myeloma, ovarian cancer, colorectal cancer, liver cancer, kidney cancer or melanoma in a mammal comprising administering to a mammal in need of such treatment an effective amount of a compound of Formula I, or a pharmaceutical!)' acceptable salt thereof
It will be understood that the amount of the compound actually administered will be determined by a physician under the relevant circumstances, including the condition to be treated, the chosen route of administration, the actual compound or compounds administered, the age, weight, and. response of the individual patient, and the severity of the patient's symptoms. Dosages per day normally fall within the range of about 0.1 to about 10 mg/kg of body weight. In some instances dosage levels below the lower limit of the aforesaid range may be more than adequate, while in other cases still larger doses may

be employed. Therefore, the above dosage range is not intended to limit the scope of the invention m any way. This invention also provides a compound of Formula I, or a phannaeeutieaSly acceptable salt thereof, for use as a medicament.
Additionally;, this invention provides use of a compound of Formula I, or a pharmaceutical!}' acceptable salt thereof in the manufacture of a medicament for treating cancer. In particular, these cancers are selected from the group consisting of niedulloblastonia, basal cell carcinoma, esophagus cancer, gastric cancer, pancreatic cancer, biliary tract cancer, prostate cancer, breast cancer, small cell lung cancer, non-small cell lung cancer, B-celi lymphoma, multiple myeloma, ovarian cancer, colorectal cancer, liver cancer, kidney cancer and melanoma.
Furthermore, this invention provides a pharmaceutical composition comprising a compound of Formula I, or a pharmaeeuricaUy acceptable salt thereof, as an active ingredient for treating medulfoblastoma, basal cell carcinoma, esophagus cancer, gastric cancer, pancreatic cancer, biliary tract cancer, prostate cancer, breast cancer, small ceil lung cancer, non-small cell lung cancer, B-cell lymphoma, multiple myeloma, ovarian cancer, colorectal cancer, liver cancer, kidney cancer or melanoma.
As used herein, the following terms have the meanings indicated: "EtjO" refers to diethyl ether; "DMF" refers to dimethylformamide; "DMSO" refers to dimethyisul.fbxi.de; "TFA" refers to trifluoroaeetic acid; "boc" or "t-boe" refers to ft'rf-butoxycarbonyl; "SCX" refers to strong cation exchange; "FyBOP" refers to benzotriazoi-1 -yioxytripyrrolidino-pliosphonium hexafluorophosphate: "prep" refers to preparation; "ex" refers to example; and "IC50" refers to the concentration of an agent that produces 50% of the maximal inhibitory response possible for that agent.


A compound of Formula I can be prepared in accordance with reactions as depicted in Scheme I.
A I -ehtoro substituted phthaiazinc (2) is reacted with a 4-amino boc protected piperidine (3a) in a micleophilic aromatic substitution (SNAr) to provide a piperidine substituted phthaiazine of formula (4), For example, the chloride (2) can be reacted with the piperidine of formula (3a) in a dipolar aprotic solvent such as DMF or DMSO, in the presence of an organic base such as txiethy famine or inorganic base such as potassium carbonate and heated to 100-140 °C.
Amine functionality, such as that present in the piperidinyi phthalaziue of formula
(4), can be deprotected and further reacted to give additional compounds of the invention.
Methods for introducing arid removing nitrogen and oxygen protecting groups are well
known in the art (see, e.g., Greene and Wuts, Prpieciiw.GToupsin.Or^ 3K
Ed., John Wiley and Sons, New York, (1999)). For example, hoc deproteetiort of the amino piperidiny! phthaiazinc of formula (4) can be accomplished under acidic

conditions, such as hydrogen chloride or trifluoroacetic acid. Alternatively, HO can be generated in situ by dropwise addition of acetyl chloride to a solution of an alcohol solvent such as methanol iii toluene at 0-20 "C followed by the addition of a compound of formula (4) and heating the solution to 30-60 °C to give a compound of formula (5). It will be obvious to one skilled in the art that a compound of formula (5) can be isolated as a salt such as the 'hydrochloride amine salt and carried on to Step 3 or transformed to the free amine using an inorganic base such as potassium carbonate. The 4-amino piperkline can be acylated using a substituted benzoyl chloride in an inert solvent such as dkhloromelhane or dioxane and a base such as oiethylamine or pyridine to give an amide compound of Formula 1. Alternatively, a compound of formula (5) can be acylated using a substituted benzoic acid with an appropriate coupling reagent such as PyBOP and an appropriate base such as triethylamine in an inert solvent such as dichloromethane or using l-(3-dimethyiammopropyl)-3^tlvylcarbodiimide hydrochloride and 1-hydroxybenzotriazole in a dipolar aprotie solvent such as DMF.
Alternatively, a l~ch.Soro substituted phthalazine (2) is reacted with an N-ptperidine-4-yl-benzanikle of formula. (3b) in a nucleophiiic aromatic substitution (SNAr) as previously described for Step la to directly give a compound, of Formula I. For example, the chloride (2) can be reacted in a dipolar aprotie solvent such as DMF or DMSO, with a A''-p.tpe.ridine-4-yi-benzaiaide of formula (3b), in the presence of a base such as triethylamine and heated to 80-140 °C to give an amide of Formula I.
It will be appreciated by the skilled artisan, that compounds of formula (2) in Scheme 1 are commercially available or can be readily prepared by methods similar to those described herein or by using procedures that are established in the art. For example, a 2-phenylcarbonyl benzoic acid, generated from a Grignard reaction of a phenyl bromide with phthaiic anhydride, can be cyclized with hydrazine to give a 4-plieny!-2fl-phthalazin-1 -one. Subsequent treatment with phosphorous oxyehloride provides the l-ehloro-4-phenyi-phthalazine of formula (2). Alternatively, 1,4-dichiorophthaIazine can be reacted with a phenyl boronic acid in a Suzuki cross-coupling reaction to give the corresponding l-chloro-4~phenyl-phthalazine of formula (2).


A compound of Formula I cart be prepared in accordance with reactions as depicted in Scheme 2. In Step i „ a 1,4-dichlorophthalazme (6) can be reacted with a 4-amino hoc protected piperidine (3a) in a dipolar aprotic solvent such as iV-methylpyt'foHdone or DMSO with an appropriate base such as potassium carbonate or triethyiamine. The mixture is heated at 70-95 °C to give a compound of formula (7). In one method, shown in Step 5, a compound of formula (7) can be deprotected and subsequently acyiated at the amine in Step 6 using a substituted benzoyl chloride in an inert solvent such as dichiorc-mechatie, with a base such as triethyiamine to give an amide

of formula (9). Alternatively, a compound of formula (7) can be acylated using a substituted phenyl earboxylic acid and an appropriate coupling reagent such as PyBOP and a suitable base such as triethylarnine in an inert solvent such as diehloromethane at room temperature or using 1 -hydroxybenzotriazoSe and 1 -(3~diraethylarnmopropyl)-3-ethylcarbodiimide hydrochloride with an appropriate solvent such as DMF. In Step 7, the phthaiazinyi chloride of formula (9) is reacted with a phenyihoronic acid under Suzuki-Miyaura cross coupling conditions. The skilled artisan will recognize that there are a variety of conditions useful for facilitating such cross-coupling reactions. The reaction conditions make use of a suitable solvent such as dioxane/water. The reaction is accomplished in the presence of a base such as potassium phosphate trihasic monohydrate, sodium carbonate, potassium carbonate, or cesium: carbonate. The reaction takes place in the presence of a palladium: catalyst such as
tfis(dibenzylideneaceto«e)dipalladiu:iii (0) with trkyelohexylphosphine or (SP-4- i )-bisj b.ts(l ,1 -dimeihylethyl)(4-mcihoxyphcnyl)phosphme-KPjdtchloro-pailadium {prepared according to the synthesis of catalyst D in J. Org. Chem. 2007, 72, 5104-5112) under an inert atmosphere at a temperature of about SO-160 °C to give a compound of Formula I.
Alternatively, the pbthalarinyl chloride of formula (7) can be initially coupled with a phenyl boronic acid as shown in Step 2 under Suzuki-Miyaura conditions as described previously to give a phenylphthalazme of formula (4). In Step 3, a compound of formula (4) can be deproteeted and then acylaied as shown in Step 4 at the amine using a substituted benzoyl chloride or phenyl earboxylic acid as described previously to give a compound of Formula 1.
The following Preparations and Examples are provided to illustrate the invention in further detail and represent typical syntheses of the compounds of Formula I. The names of the compounds of the present invention are generally provided by ChemDraw Ultra® 10.0.
Preparation 1
{l-[4^4-Fluoro-phenyi)phthalazin-l-ylj-piperidm-4-yl}-iTiethyi-carbamic acid tert-butyl
ester


Add 1 -chtoro-4-(4-fiuorophcnyl)-phthalazine (3.00 g, 1 ] .6 ramol) to a solution of methyhpiperidi»-4-yl~carbar»ic acid few-butyl ester (2.98 g, 13.9 mmol) and triethylamine (3,52 g, 34.8 mmol) in DMF (30 mL). Heat at 130 °C for 3 days. Dissolve the reaction mixture in dichloromethane and wash with brine. Dry the organic phase with sodium sulfate, fitter, and concentrate under reduced pressure. Purify the resulting residue by flash chromatography (20:5:1, hexarte:ethyi acefate:2 M ammonia in methanol) to yield the title compound as a solid (4.45 g, 88%). ES/MS m/z 437.2 (M-H). Alternate procedure;
Combine mefhyi-piperidin-4-yl~carbarmc acid tert-huty] ester (75 gT 349 mmoi'X ]-chloro-4-(4-fluoro-phenyl)~phthalazine (75 g, 289 mmol), and potassium carbonate (80 g5 579 mmol) in dimethyl sulfoxide (500 mL) and heat the mixture to 110 °C for 3 h. Cool the reaction to ambient temperature and pour the slurry into water (1.0 L). Collect the solids by filtration and dry in a vacuum oven for 3 days to provide the title compound as a white solid (120 g, 95%). ES/MS m/z 437.3 (M+l).
Prepare the piperidinylphtlmlazioes in the table below by essentially following the procedure described in Preparation i, using the appropriate eMoropfothalazine and tBOC protected aminopiperidine:


Add trifluoroacetic acid (100 ml.) to a solution of 1 l-[4~(4-fluoro-phenyl)pfethalaziiJ-.l-yl]-piperidm-4-yl}-methyl~carbaraic acid tert-butyl ester (11.2 g„ 10.2 mmol) in dichloromeihane (100 mL), Stir tbe reaction at room temperature overnight; and concentrate under reduced pressure. Dissolve the ■resulting residue m dichloromethane and wash with 1 N NaOH and brine. Dry the organic phase with sodium sulfate, filter, and concentrate under reduced pressure. Crystallize the title compound from iiexane/dic'lilorottiethane to obtain the title compound (8.46 g, 98%). ES/MS m/z 337.2 10Q%) as is. ES/MS m/z 387.0 (M+I).
Preparation 12
tert-Boty! l-(4^4-c^'anophcnyl)phthalazin-l-yl)piperidm-4-y!(meth.yJ)carbamate Charge a pressure tube with tert~b\xty\ l~(4~chlor0phtha.lazin~l~yi)piperidin~4~ yi(i»ethyl)earbamate (400 rag, 1.06 mraoi), 1,4-dioxane (.12 mL), water (4 mL), 4-cyatiophenylboronic acid (467 trig, 3.18 mmol), and cesium carbonate (1.40 g, 4.24 mmol). Bubble nitrogen through the reaction mixture for 5 min. Add (SP-4-1 )-bis[bis(lJ-dimetI\yletliyi)(4-methoxypheny!)phospliine-KP]dicli!oro-pal!adiurii(J. Org. Chem. 2007, 72, 5104-5112) (36.0 mg, 0.053 mmol). Bubble nitrogen through the reaction mixture for a few minutes and seal the reaction vessel. Heat the reaction at 90 °C overnight. Filter the reaction mixture through a silica gel pad eluting with ethyl acetate. Remove the solvents under reduced pressure and purify the resulting residue using silica gel chromatography (30:70, ethyl acetate:hexane) to obtain the title compound (0.392 g, 83%). ES/MS m/z 444.2 (Mtl).

Preparation .13
4^4-(4-(Methytammo)piperidm-i-yt)phthalazin-]-yl)benzo«itrUedihydroch]oride Prepare the title compound, by essentially following the procedure as described in Preparation i 1 using fc.r/-butyl i-(4-(4-cyanopfeenyI)phthalazin-i~yl)piperidin~4-yi{-methyl)carbamate (0.385 g, 0.868 irtmoi). Use the crude material (0378 g, >10O%) as is in subsequent reactions. ES/MS m/z 344.2 (M+i).
Preparation 14
i. -(4-Chtorophrhalazin-1 -yi)-A-methylpjperidin-4-amine dthydrochloride Add hydrogen chloride (4.0 N in dioxane, 100 mL; 400 mmol) to a solution of /er/-hutyl 1 -(4~chIorophthaiazin-i-yl)piperidin~4-yUmeihyl)carbamate (7.60 g; 1,00 equiv; 20,2 mmol) i» methanol (100 mL), Stir at room temperature one hour. Remove the solvent under reduced pressure to obtain fee title compound (7.05 g, 100%). ES/MS m/z 277.2 (M+l).
Preparation 15
iV~( I -(4-Chlo.rophthalazin-1 -yl)piperi.din-4-yJ}-.Ar-methyl~2-(trifl uoromethyl)benzamide

t Combine 1 -(4-ehiorophthalazin-! -yl)-A'-methylpiperidin~4-arnine dihydrochloride
(1.01 g, 2.89 mmol) and triethyiamiiie (1,2 mL, 8.61 mmol) in dichJoromethane (30 mL). Flush the reaction vial with nitrogen and add 3-trirluoromethyibenzoyl chloride (0.46 mL, 3.1.2 mmol). Place the reaction under a nitrogen blanket md stir at room temperature overnight. Concentrate to a residue and purify using silica gel chromatography (0-10% methanol in dichSoromethane) to obtain the title compound (1.11 g„ 86%). ES/MS m/z 449,2 (MH).

Prepare the amides in the table below by essentially following the procedure described m Preparation 15, using the appropriate acid chloride;

Example 1
.<¥-( 1 -(4-(4-FluorophenyI)phthalazi«-1 -y l)piperidin-4-yl)-N-methy 1-4-(U'inuoromethoxy)benzamide hydrochloride

Combine methyl {I -{4-(4-fluoro-phenyl)phthalazin-1 -yfjpiperidin-4-y!}methylamine f 100 mg, 0.300 mmol). triethy famine (0.12 mL. 0.89 mmol) and dichloromcthane (2 mL) at room temperature. Add 4-(mfl.uoromethoxy>bcnzoyl chloride (100 mg, 0.45 mmol) to the mixture and stir at room temperature overnight. Concentrate the reaction mixture and purify the resulting residue by Hash chromatography (20:5:1, hexaoe:efriyi acetate:2 M ammonia in methanol). Add 1 N HC1 in diethyl ether to a solution of fee isolated product in diehloromethane/methanol and remove the solvents under a stream of nitrogen gas to yield the title compound as a solid (98 mg, 58%). ES/MS m/z 525.0 (M-M), Alternate procedure:
Add {i~[4-(4-fluoro-phenyl)-phtha.iazin-i~yi]-piperidi:n-4-yl}-methyl-amine hydrochloride (58 g, 1.55 mmol) to 1,4-dioxane (580 mL). Add tricthylamine (86 mL, 622 mmol) and stir for 20 mm. Add 4-(trifiuoromethoxy)bcnzoyl chloride (24 mL,l 55 mmol) dropwise over a period of 20 miu. Stir for one hour at ambient temperature. Add water (100 mL), extract with ethyl acetate (200 mL), and concentrate the organic portion

under reduced pressure. Purify the resulting residue by (lash chromatography, eluting with ethyl acetate over a I kg silica plug to yield the product as a colorless oi! (58 g, 71%), Combine toluene (586 mL) with ethanoi (1 ]7 mL) aed cool to 3 °C. Add acetyl chloride (8 mL, .111 mmoi) over a period of 20 rain. Stir for 20 rain and then add A'-{ 1 -|4K4-fIuoro-phenyl)-phthalaxin-i-yi]-piperidiri-4-yI}-Air~methyJ-4-trii1uoromethoxy-berrzamkle (58 g, 11I mmal) in toluene (40 ml.) in one portion. Stir for 12 h. Concentrate to 1/3 volume. Collect the precipitate by filtration. Dry the solid in a vacuum oven at 40 °C overnight to afford the title compound as a white solid (42 g, 67%). ES/MS ra/z 525.0 (M-f I).
Prepare the amides in the table below, by essentially following the procedure described in Example L using the appropriate acid chloride:





Alternate procedure to Example 30:
Add {5-[4~(4-fluora-pheHyl)~phthaiaziH-.J-ylj-piperidiri-4~yl}-methyl-amine hydrochloride (80 g, 240 mraol) to water (500 mL) to form a slurry. Add potassium carbonate until the pH is 10, Add methylene chloride (400 ml). Stir vigorously until all the solids dissolve. Separate the organic layer and concentrate to a clear oil (74 g, 220 niraoi) to afford l-[4-(4~fluoro-phenyl)-phthaiaziri~l-yr|~piperidin-4-yl}-metJiyNaiijine.
Combine {I-f4-(4-fliJoro-phenyl)-phfealazm-I-ylj-piperidin-4-y!}-rnethyi-arnine (12 g, 35 mmol), pyridine (20 mL, 247 mmol) and 1,4-diox.ane (120 mL). Stir the reaction for 20 mm. Add dichioroniethane (25 mL). Stir the slurry lor 20 rain. Add 4-fluoro-2-(triiluoromediy.l)benzoyl chloride (6.5 ml.,, 43 mraol) dropwise over a period of 20 min. Stir lor 2 h. Pour tlie mixture into water (.100 mL), extract with dichioroinethane (200 mL) and concentrate under reduced pressure. Purify the residue by flash chromatography (1:1, ethyl acetate.'hexane) to yield the product as a white solid (10.3 g5 55%). Add 4-fluoro-iV- {I,-{4-(4-fluoro-phenyl)-phthala;zm-l~y!j-piperidin-4-yl J-A-methyl-2-trifluororaethyi-benzairiide (10 g, 19.85 mmol) to toluene (125 mL) to obtain a slurry. Add methanol (30 mL) to make a homogenous solution. Add hydrogen chloride

(5.21 mL, 4.0 N in 1,4-dioxane, 20 mmol) in one portion. Allow to stir for one hoar and concentrate to 1 /3 volume. Collect the solid and dry in a vacuum oven for 12 h at 35 °C to obtain the title compound as a white solid (9.5 g, 85%). ES/M.S m/z 527.0 (M-H).
Example 31
4-F]iwro-Ar-raethy]~AJ-(.}-(4~phenylphthalaxia-l~yt)piperidin~4-y!)~2-
(frifhK>roroefhyl}benzaro.ide hydrochloride

Combine metiiyJ-[l-(4-phenylphthaiaziii-l-yl)pjperidin-4-yl)-araiTie (BOO mg, 2.51 o.imo!), triethylaraine (LOS mL, 7.54 mmol) and dichloromethane (20 mL) at room temperature. Add 4-fliioro-2-(tri:fluoromethyl)beozoyl chloride (683 mg, 3.01 mmol) to the mixture and stir at room temperature overnight. Concentrate the reaction mixture and purify the resulting residue by flash chromatography (20:5:1, hexaee:ethyl acetate:2 M ammonia in methanol). Add 1 N HO in diethyl ether to a solution of the isolated product in diehloromethane/methanoi. Filter the resulting solid to obtain the title compound (1.13 g, 88%). ES/MS m/z 509.2 (M-M).
Prepare the amides in the table below by essentially following the procedure described in Example 3!, using the appropriate acid chloride. Isolate the .HO salt by filtration or by evaporating the solvent:





Example 49
N'( 1 -(4- (4-Fluoroph.etry l)phf halazin - i -y1)piperidra-4- yI)-4-(t:ri£l uoromethy !)benzamide
hydrochloride

Combine l-(4-{4-fluoropheriyi}pbthaia7iii-i~yr}piperid):n~4-aniirie (1 iO mg, 0.34 mmol), tricthyfamine (0J4 mL,1 .02 lnmol) and dichloromethane (2 mi) at room temperature. Add 4-{iriliiforomef.liyi)-bc»zoy! chloride (85 mg, 0.41 mmol) to the mixture and stir at room temperature overnight. Concentrate the reaction mixture and purify the resulting residue by flash chromatography (20:5:1, hexa»e:ethyl acetate:2 M ammonia in methanol). Add 1 N HC1 in diethyl ether to a solution of the isolated product in dichloromethane/meihanol and remove the solvents under a stream of nitrogen gas to yield the title compound as a solid (57 mg, 32%). ES/MS m/z 495.2 (M-H).
Prepare the amides in the table below: by essentially following the procedure as described in Example 49, using the appropriate acid chloride:




Example 68
AM.! -(4-Ptie.oylphtliaIazsn-1 -yl )prpe«di n-4-y l)-4-(tritluoromethyl )benzamide
hydrochloride

Carabine 1^4-phenylphtha1az:in-.l -yl)pipem1in-4-amine (i 10 rag, 0.34 nirnol), trie thy lamine (0,140 r»L, 1.02 mrao!), and dieMoromethaiie (2 raL) at room temperature. Add 4-(triiluoromethyl)-benzoyl chloride (85 mg, 0.41. ramol) to the mixture and stir at room temperature overnight. Concentrate the reaction mixture and purify the 'resulting residue by flash chromatography (20:5:1, feexane:ethyl aeetate:2 M ammonia in methanol). Add J N HCI in diethyl ether to a solution of the isolated product in dichloremethane/methanol and remove the solvents by placing under a stream of nitrogen gas to yield the title compound as a solid (116 mg, 67%). ES/MS m/z 477.2 (M-H).
Prepare the amides in the table below by essentially following the procedure described in Example 68, using the appropriate acid chloride:



Example 86
i?v-(I-(4-(4-F!uorophe«yl)phthalaz!«-1 -y!)psperf dm-4-yl)benzamide hydrochloride

Combine l-chk>ro-4-(4-fluojx>p!icoyl)phf!ialazi.oe (150 jag, 0.58 aimol), .<¥-(piperidi.ri-4-yl)beazam,ide (178 rag, 0.87 mraol), friethyla.aii.oe (0.404 mL, 2,9 aimol) and diniethylfotmarmde (1. mL) at room temperature. Heat to 100 °C and stir overnight. Pour the crude reaction mixture onto a strong cation exchange Phenomenex. Strata3t! SCX (55 uro, 70 A) 10 g/60 mL column (with a benzene sulfonic acid functional group). Elute the desired product with 2 N raetharioiic ammonia (40 mL) and concentrate. Purify the

residue by flash chromatography (20-30% {10% 2 N methanoHc ammonia in ethyl acetate] in hexanc). Add i M hydrochloric acid in diethyl ether to a solution of the isolated product in diehlorotnethane/tnethanol and remove the solvents under a stream of nitrogen gas to yield the title compound as a solid (137 mg,, 51 %). ES/MS m/z 427.2 (M+l).
Example 87
A^1^4-(4-Cyanophenyl)phdmlazm-l^vi>piperidin^-yl)^-nuoro-A'-mcfeyi-2-
(tri'fluoromethyl)bcnzaniidc hydrochloride

Charge a 4 niL reaction vial with 4-(4-(4-(methylammo)ptperidin-1 -yl)phthalazin-l-yl}benzo:nitrile dihydrochloride (44.7 mg, 0.107 mmoi), diehlororoethane (1 roL), and triethyl amine (0.0598 mL, 0.429 mmol). Flush the reaction vial with nitrogen and add 4-fiuoro-2-(trifiuoromethyi)benzoyl chloride (0.033 g, 0.14 mmol). Cap the vial and allow the reaction to stir at room temperature overnight. Evaporate to a residue and purity using silica gel chromatography (40:60, ethyl acetate fhexaoe, then ethyl acetate). Add i N HC! in diethyl ether to a solution of the isolated product in dichloromethane/methanol and remove the solvents by placing under a stream of nitrogen gas. Dry in a vacuum oven at 50 °C to obtain the title compound (36.0 mg, 59%). ES/MS m/'z 533.8 (M+l).
Prepare the amides in the table below by essentially following trie procedure described In Example 87, using the appropriate starting material from Preparation 11 or Preparation 13 and 4-(trif]uoromctfeoxy)benzoyl chloride:



Example 90
iV-Meihyl-2-(trifluoK)methyl)^
y!)piperidin-4-y])bcti2amidc hydrochloride

Charge a microwave vessel with A'-(i-(4-ch1orophthalazi.r)-l-yi)piperidin-4-yl)-A'-methyl-2-(trifluoremeth\4)henzamide (0.101 g, 0.23 mmol), 4-
(trifluoromethyj)phenyjboronie acid (0.171 g, 0.9 rriraol), cesium carbonate (0.295 g, 0.91 mmol), 1,4-dioxane (3 ml,), and water (1 ml,). Purge the reaction vial two times with nitrogen. Add (SP-4-1)- bis[bis( 1,1 -dimethylemyl)(4-methoxyphenyl)phosphirie-tcP|dichloro-palladmm (./ Org. Chem. 2007, 72, 5104-5112) (0,002 g; 0.003 mmol) and heat the reaction at 90 °C for 16 h. After cooling, separate the two layers and remove the water. Evaporate the organic solvent with a stream of "nitrogen. Purify the residue from the organic layer using silica gel chromatography (0-10% methanol iii dichioromethane). Add 4 N HC! in dioxane to a solution of the isolated product in methanol and remove the solvents in vacuo to obtain the title compound (OJOO g, 75%). ES/MS m/z 559.2 CM+1).
Prepare the compounds in the tabic below, by essentially following the procedures described in Example 90, using the appropriate starting material from Preparations 15-1.8 and the appropriate borome acid:




The Sonic Hedgehog (Shh) pathway is critical during embryogenesis, but is d-ownregulated after early postnatal development in most tissues, la contrast, more than 30% of human medulioblastonia exhibit high levels of QUI (giioma-associated oncogene iiomolog 1} expression, indicating that abnormal activation of the Shh pathway is important in a subset of pediatric brain tumors. Cerebellar Purkinje cell-secreted Shh promotes the proliferation of granule progenitors, indicating that uncontrolled activation of hedgehog (Hh) pathway may sustain the development of medulioblastonia. This hypothesis is confirmed by the development of medullobiastoma in Patched gene (Pick'') mice. Treatment of these mice with a hedgehog antagonist inhibited tumor growth, furthermore, it is documented that hedgehog antagonist treatment resulted in inhibition of Gtil expression in these brain tumors.
Uncontrolled hedgehog pathway activity has been reported in a number of other cancers as well. For example, hedgehog has been implicated as a survival factor for the following cancers: basal cell carcinoma; upper gastro intestinal tract cancers (esophagus, stomach, pancreas, and biliary tract); prostate cancer; breast cancer; small cell lung cancer; non-small ceil lung cancer; B-eell lymphoma; multiple myeloma; gastric cancer; ovarian cancer; colorectal cancer; liver cancer; melanoma; kidney cancer; and medullobiastoma.
Elements of the hedgehog pathway have been asserted to be potential drug targets for the treatment of cancers. A Daoy ceil line established from medullobiastoma tumor (ATCC, HTB-S 86), is responsive to Hh ligands. When these cells are treated with

exogenous!;/ added Shh-conditioned media, Hh signaling pathway is activated and results m an increased expression of GUI. Cyclopamine, an alkaloid isolated from the com lily Femtrmt catifornicum is a weak hedgehog antagonist and has been shown to suppress the expression of 67/7 in response to Shh stimulation. Recent observations suggest that cycioparaine inhibits the growth of cultured nredulloblastoma cells and allografts. Using this Daoy ceil model system, potent inhibitors of hedgehog signaling pathways can be identified. Since the compounds of the present invention are hedgehog antagonists, they are suitable for treating the aforementioned tumor types.
Determination of Biological Activity IC50 The following assay protocol m\d results thereof further demonstrating the utility and efficacy of the compounds and methods of the current invention are given for the purpose of illustration and are not meant to be limiting in any way. Functional assays provide support that the compounds of the present invention exhibit the ability to inhibit Shh signaling. All Sigands, solvents, and reagents employed in the following assay are readily available from commercial sources or can be readily prepared by one skilled in the art.
Biological activity is determined using a functional assay in Daoy neuronal cancer ceils and measures levels of GUI ribonucleic acid via a h-DNA {branched deoxyribonucleic acid) assay system (Panomics, Inc., Fremont, CA). Gli was originally discovered in a Glioblastoma cell, line and encodes a zinc finger protein that is activated by Shh signaling. The maximum response is obtained by inducing GUI transcription in the Daoy cells with conditioned medium (HEK-293 cells stably expressing recombinant Shh) for 24 hours and then measuring the amount of stimulated GUI transcript. The minimum response is the amount of GUI transcript inhibited with a control compound in Daoy cells that have been stimulated with conditioned media (human embryonic kidney, (HEK)-293 ceils stably expressing recombinant Shh) for 24 hours.
Functional Assay for Measuring the Inhibition of Gill in Daoy eel Is The bDNA assay system utilizes the technology of hranched-chain DNA to allow amplification of a target ribonucleic acid (transcript). The technology employs three

types of synthetic hybrid short Git J -specific cDNA probes that determine the specificity of the target transcript (capture extenders (CEs), label extenders (LEs), arid blockers (BLs)) that hybridize as a complex with the target transcripts to amplify the hybridization signal. The addition of a ehemilumigenic substrate during the amplification, step allows for detection using luminescence.
The I>aoy ceil line obtained from. American Type Culture collection (ATCC) is a Shh-responsive human neuronal minor cell line and was established in 1985 from a desraoplastic cerebellar medullablasioma tumor, a physiologically relevant tumor cell line. Endogenous levels of GUI transcripts levels are low in Daoy cells but can be stimulated by using conditioned media taken from cells stably over-expressing human Shli (a HEK-293 cell line stably transfected with hShh).
Daoy cells are grown to ecmfluency in tissue culture T22S-flasks in Daoy growth media containing Minimum Essential Medium (MEM) plus 10% Fetal Bovine Scrum (FBS) with 0.1 iiM non-essential amino acids and 1 raM sodium pyruvate. The ceils are removed from the T225-f!asks using trypsin ethytenediaminetetraacehc acid (EDTA), ceotrifuged, resuspendecl in media, and then counted.
The Daoy cells are then seeded at 50,000 cells per well in growth media in Costar 96 well clear tissue culture plates and allowed to incubate overnight at 37 '3C under 5% carbon dioxide (CO?). The cells arc washed one time in phosphate buffered saline (PBS) followed by addition of 100 u.L of Shh Conditioned Media (Shh-CM) to stimulate levels of GUI expression. Shh-CM is diluted to achieve maximum stimulation, using control growth media ~ 0,1% FBS/DMEM (Dulbeccos Modified Eagle Medium). Daoy cells treated with Shh-CM are then treated with various concentrations of hedgehog inhibitors at concentrations ranging from approximately 1 uM to 0,1 nM, Compounds are allowed to incubate for 24 hours at 37 °C under 5% CCh.
The measurement of the GUI transcript is performed by using the Quaotigene 2.0 GUI assay as described by the manufacturer (Panomics, Inc.), Prepare a diluted lysis mixture (D.LM) buffer, which includes Proteinase K. After a 24 hour incubation with compound, the cells are washed one time with PBS and 180 u.L of DLM is added to the cells. The cell plate containing the lysis buffer is sealed and placed at 55 °C for 30 to 45 minutes. The resulting cell lysates are then triturated 5 times, A working probe set

containing GUI probes is made by diluting the probes in the DLM according to manufacturer's directions, and then 20 j-il, of the working probe set is added to the fa'DNA assay plates along with 80 uL of the Daoy ly sates. The plates are scaled and incubated overnight at 55 °C. The bDNA plates are then processed according to the manufacturer's directions. The signal is quantified by reading the plates on a Perkin Elmer Envision reader defecting luminescence. The luminescent signal, is directly proportional to the amount of target transcript present in the sample.
The luminescent signal data horn the functional assay are used to calculate the IC50 for the in vitro assay. The data are calculated based on the maximum control values (Daoy cells treated with Shh-CM) and the minimum control value (Daoy cells treated with Shh~CM and an inhibitory concentration of a control compound, I uM of N-(3-(l ii-benzo|d|im:ida2oi-2-yl}-4-chiorophenyl)-3,5-dimethoxyben2araide}. A four parameter logistic curve fit is used to generate the IC50 values using Activity Base software programs vs. 5.3. equation 205 (Guidance for Assay Development and HTS, vs 5, Copyright 2005, Eli Lilly and Co, and The National Institutes of Health Chemical Genomics Center), The 4 parameter equation is as follows; Fit ~ (A+((B-A)/(R((Ox}'vD)}} where A==Botrom, B==Top, O4C50 and D==TifH Coefficient, Following the protocol described, the compounds exemplified herein display an 1.C50 of < 30 nM. The compound of Example 36 has an IC50 of approximately 2.3? nM with a standard error of 0.150 (n:::2) in the assay described above. These results provide evidence that the compounds of the present invention are hedgehog antagonists and as such are useful as anticancer agents.

WECLAIM:-
1. A compound of the following formula:

wherein:
R1 is hydrogen, fluoro, cyano, trifluoromethyl, methoxy, or trifluoromethoxy;
R2 is hydrogen or methyl; and
R3, R4, R5, R6 and R7 are independently hydrogen, chloro, fluoro, cyano, trifluoromethyl or trifluoromethoxy, provided that at least two of R3, R4, R5, R6 and R7 are hydrogen; or a pharmaceutically acceptable salt thereof.
2. The compound of claim 1 wherein R^s hydrogen, or a pharmaceutically acceptable salt thereof.
3. The compound of claim 1 wherein R1 is fluoro, or a pharmaceutically acceptable salt thereof.
4. The compound according to any one of claims 1-3 wherein R2 is methyl, or a pharmaceutically acceptable salt thereof.
5. The compound according to any one of claims 1-3 wherein R2 is hydrogen, or a pharmaceutically acceptable salt thereof.
6. The compound according to any one of claims 1-5 wherein R3 is chloro, fluoro, trifluoromethyl or trifluoromethoxy, or a pharmaceutically acceptable salt thereof.

7. The compound according to any one of claims 1-6 wherein R5 is fluoro, trifluoromethoxy or trifluoromethyl, or a pharmaceutically acceptable salt thereof.
8. The compound according to any one of claims 1-7 which is 4-fluoro-N-(1-(4-(4-fluorophenyl)phthalazin-1-yl)piperidin-4-yl)-N-methyl-2-(trifluoromethyl)benzamide, or a pharmaceutically acceptable salt thereof.
9. A pharmaceutical composition comprising the compound according to any one of claims 1-8, or a pharmaceutically acceptable salt thereof, in combination with a pharmaceutically acceptable carrier, diluent or excipient.

10. The compound according to any one of claims 1-8, or a pharmaceutically acceptable salt thereof, for use as a medicament.
11. The compound according to any one of claims 1-8, or a pharmaceutically acceptable salt thereof, for use in the treatment of cancer.
12. The compound according to claim 11 wherein the cancer is selected from the group consisting of medulloblastoma, basal cell carcinoma, esophagus cancer, gastric cancer, pancreatic cancer, biliary tract cancer, prostate cancer, breast cancer, small-cell lung cancer, non-small cell lung cancer, B-cell lymphoma, multiple myeloma, ovarian cancer, colorectal cancer, liver cancer, kidney cancer, and melanoma.