[0001] The invention concerns the field of organic polysulphides and more particularly to a method of synthesizing functionalized organic polysulfides.
[0002] The organic polysulfides are used in many applications. Indeed, according to the functions they carry, they can be used as additives for lubrication, as an anti-wear, extreme pressure agent or anti-oxidant. They are also used during the presulfiding hydrotreatment of oil cuts or curing catalysts. They can also enter into the composition of lubricant formulations, eg for gearboxes and for machining materials. Furthermore, they can be used in the manufacture of cement, concrete or bitumen. Finally, they can enter into the composition of some anti-radiation drugs or other therapeutic uses.

[0003] Thus, depending on the desired organic polysulfide, there are many synthetic compounds such processes.

[0004] For example, in the industry, the organic polysulfides are commonly synthesized by a reaction process between a mercaptan, sulfur and a basic catalyst. They can also be prepared by a reaction process between an oil or renewable olefin with sulfur and hydrogen sulfide. However, these methods of obtaining organic polysulfide require conditions of temperature and / or high pressures in order to be effective.

[0005] It is readily understood that, by the multitude of possible applications of functionalized organic polysulfide, there is still a need to provide the synthesis of these processes.

[0006] It is also understood that there is also a need for syntheses of organic polysulfide functionalized with methods that can be called sustainable, that is to say achievable with mild conditions of temperature and pressure, in aqueous solution with pH close to neutral, and with raw materials of renewable origin, and whose returns are higher than those obtained with existing processes, and generally using more environmentally processes.

[0007] It has now been found possible to meet Ojectives defined above by implementing the method according to the invention and as described below. Other objectives become apparent from the following description of the invention that follows.

[0008] Thus, according to a first aspect, the present invention relates to a method of synthesis of at least one organic polysulfide functionalized of formula (I):

R 2 -X- (R7) C * H- (CH2) n-Sa- (CH2) NC * H (R 7 ) -X-R2 (I)

in which

- R and R 7 , or not different, are hydrogen or a hydrocarbon chain branched or unbranched, saturated or unsaturated, linear or cyclic, aromatic or not, of 1 to 20 carbon atoms, which may contain heteroatoms;

- X is -C (= 0) - or -CH 2 -, or -CN;

- R2 is (i) zero (when X is -CN), (ii) hydrogen, (iii) -OR3, wherein R3 is hydrogen or a branched hydrocarbon chain or unsubstituted, saturated or unsaturated, linear or cyclic, aromatic or not, of 1 to 20 carbon atoms which can comprise heteroatoms, or (iv) NR4R5, R 4 and R 5 , or not different, being hydrogen or a branched hydrocarbon chain or unsubstituted, saturated or unsaturated, linear or cyclic, aromatic or not, of 1 to 20 carbon atoms, which may contain heteroatoms;

- n is 1 or 2;

- a is an integer or decimal number between 2 and 10, preferably between 2 and 6; and

- * represents an asymmetric carbon;

said method comprising the steps of:

a / providing at least one compound of formula (II):

G- (CH 2 ) NC * H (R 7 ) -X-R2 (II)

in which

- n, R, R 2 , R 7, X and * are as defined above,

- G represents either (i) R 6 -C (= 0) -0-, or (ii) (R 8 0) (R 9 0) -P (= 0) -0-, or (iii) R 8 0 -S0 2 -0-;

- R6 is hydrogen or a branched hydrocarbon chain or unsubstituted, saturated or unsaturated, linear or cyclic, aromatic or not, of 1 to 20 carbon atoms, which may contain heteroatoms;

- Re and Rg, identical or different, being a proton H, alkali, alkaline earth or ammonium, preferably a proton H or an alkali, and more particularly to a proton H or Na;

b / providing at least one inorganic polysulphide;

cl reaction between said at least one compound of formula (II) and said at least inorganic polysulphide in the presence of at least one enzyme selected from sulfhydrylases, and preferably a sulfhydrylase associated with said compound of formula (II);

61 obtaining at least one functionalized organic polysulfide of formula (I);

e / separating and isolating said at least functionalized organic polysulfide of formula (I) and;

f / optionally, further functionalization of the functionalized organic polysulfide of formula (I) obtained in step d / or e /;

steps a / and b / is or not performed simultaneously.

[0009] It has been observed that the configuration of asymmetric carbon atoms is maintained throughout the reaction. As a further advantage, it should be noted that the organic polysulfide functionalized of formula (I) obtained according to the method of the invention is an enantiomerically pure organic polysulfide.

[0010] The term "organic polysulfide functionalized" is meant any type of organic polysulfide of formula (I) in which the nitrogen atom carries a functional group (except when R represents the hydrogen atom) and / or carbon atom alpha to the nitrogen atom carries a functional group (except when -X- is -CH2- and R2 the hydrogen atom).

[0011] The invention will be better understood in light of the description and the following examples but is in no way limited to the said examples.

[0012] According to a preferred embodiment, Ri and R 7 represent hydrogen.

[0013] According to another preferred embodiment, X represents the -C (= 0) -.

[0014] According to another embodiment, R2 is -OR3, wherein R3 is hydrogen.

[0015] According to another embodiment of the invention, n is 1.

[0016] According to yet another embodiment of the invention, n is equal to 2.

[0017] According to a preferred embodiment of the invention, in formula (I), R represents a hydrogen atom, X is -C (= 0) -, R2 represents OR3 with R3 being a hydrogen, n is 1, and the compound of formula (I) is polysulphide dicystéine.

[0018] According to another preferred embodiment of the invention, in formula (I), R represents a hydrogen atom, X is -C (= 0) -, R2 represents OR3 with R3 being hydrogen, n is 2, and the compound of formula (I) is polysulphide dihomocystéine.

[0019] According to a preferred embodiment of the invention, in formula (II), R represents hydrogen, X represents the function C = 0, R 2 represents -OR 3 with R 3 being hydrogen, n is 1 and the compound of formula (II) is a derivative of L-serine.

[0020] The Hyper L-serine used in the invention procédé selon le, par exemple and not limiting way, they Das Models ΓΟ-phospho-L-serine, O-succinyl-L-serine, the ' O-acetyl-L-serine, ΓΟ-acétoacétyl-L-serine, ΓΟ-name-L-serine, O-coumaroyl-L-serine, ΓΟ-malonyl-L-serine, ΓΟ-hydroxyméthylglutaryl-L-serine, ΓΟ-pimélyl-L-serine and ΓΟ-sulfato-L-serine.

[0021] De manière music, drifts of L-serine is Das Models ΓΟ-phospho-L-serine, ΓΟ-succinyl-L-serine, ΓΟ-acetyl-L-serine and ΓΟ-sulfato-L-serine.

[0022] Most preferably, the L-serine derivative is O-acetyl-L-serine.

[0023] According to another preferred embodiment of the invention, in formula (II), R represents hydrogen, X represents the function C = 0, F¾ represents -OR 3 with R 3 being hydrogen , n is 2 and the compound of formula (II) is a derivative of L-homoserine.

[0024] The derivative of L-homoserine used in the process according to the invention may, for example and without limitation, be selected from O-phospho-L-homoserine, O-succinyl-L-homoserine , ΓΟ-acetyl-L-homoserine, O-acetoacetyl-L-homoserine, O-propio-L-homoserine, O-coumaroyl-L-homoserine, O-malonyl-L-homoserine, L O-hydroxymethylglutaryl-L-homoserine, ΓΟ pimelyl-L-homoserine and O-sulfato-L-homoserine.

[0025] Preferably, the derivative of L-homoserine is selected from O-succinyl-L-homoserine, O-acetyl-L-homoserine, O-phospho-homoserine and O-sulfato -L-homoserine.

[0026] Most preferably, the derivative of L-homoserine is O-acetyl-L-homoserine (OAHS).

[0027] The derivative of L-serine and the derivative of L-homoserine are either commercially available or obtained by any known to those skilled in the art.

[0028] They can for example be obtained by fermentation of a renewable raw material. The renewable raw material may be selected from glucose, sucrose, starch, molasses, glycerol, ethanol, preferably glucose.

[0029] The derivative of L-serine can also be produced from the acetylation of L-serine, L-serine, which can itself be obtained by fermentation of a renewable raw material. The renewable raw material may be selected from glucose, sucrose, starch, molasses, glycerol, ethanol, preferably glucose.

[0030] The derivative of L-homoserine can also be produced from the acetylation of L-homoserine, L-homoserine, which can itself be obtained by fermentation of a renewable raw material. The renewable raw material may be selected from glucose, sucrose, starch, molasses, glycerol, ethanol, preferably glucose.

[0031] The inorganic polysulphide used in the process according to the invention has an average rank sulfur integer or decimal between 2 and 10, preferably between 2 and 6.

[0032] The inorganic polysulphide is selected from alkali metal polysulfides, alkaline earth and ammonium salts.

[0033] Preferably, the inorganic polysulphide is selected from the sodium polysulfide, potassium polysulfide, calcium polysulfide and ammonium polysulfide.

[0034] Particularly preferably, the inorganic polysulfide is sodium polysulfide.

[0035] The inorganic polysulphide is prepared from hydrosulfide or sulfide according to any technique known to the skilled art. Hydrosulphide or sulphide used may be a sulphide or an alkali metal sulfide, alkaline earth metal or ammonium

[0036] The inorganic polysulphide may also be prepared from hydroxides, oxides, hydrogen sulfide or sulfur.

[0037] The amount of sulfur added is adjusted based on the desired average sulfur rank for the inorganic polysulphide.

[0038] In the process according to the invention, the reaction between said at least one compound of formula (II) and said at least inorganic polysulphide is carried out in the presence of at least one enzyme, said enzyme being preferably associated sulfhydrylase to said compound of formula (II).

[0039] Thus, when the compound of formula (II) is a derivative of L-serine, the enzyme that can be used is selected from sulfhydrylase ΓΟ-phospho-L-serine, O-succinyl-L-serine sulfhydrylase, sulfhydrylase ΓΟ-acetyl-L-serine sulfhydrylase ΓΟ-acetoacetyl-L-serine, O-sulfhydrylase propio-L-serine sulfhydrylase ΓΟ-coumaroyl-L-serine, O-malonyl sulfhydrylase-L-serine the sulfhydrylase hydroxymethylglutaryl-O-L-serine, O-pimelyl-L-serine sulfhydrylase and ΓΟ-sulfato-serine sulfhydrylase.

[0040] Preferably, the enzyme associated with the derivative of L-serine sulfhydrylase is selected from O-phospho-L-serine sulfhydrylase the O-succinyl-L-serine, O-acetyl-L serine and sulfhydrylase ΓΟ-sulfate-serine sulfhydrylase.

[0041] Most preferably, the enzyme associated with the derivative of L-serine sulfhydrylase is the O-acetyl-L-serine.

[0042] When the compound of formula (II) is a derivative of L-homoserine, the enzyme that can be used is selected from O-phospho-L-homoserine, O-succinyl-L-homoserine sulfhydrylase , O-acetyl-L-homoserine sulfhydrylase, the O-acetoacetyl-L-homoserine sulfhydrylase, the O-propio-L-homoserine sulfhydrylase, the O-coumaroyl-L-homoserine sulfhydrylase, ΓΟ-malonyl-L -homosérine sulfhydrylase, O-hydroxymethylglutaryl

L-Homoserine sulfhydrylase, ΓΟ-pimélyl-L-Homoserine sulfhydrylase and ΓΟ-sulfato-L-Homoserine sulfhydrylase.

[0043] Preferably, the enzyme associated with the derivative of L-homoserine is selected from ΓΟ-phospho-L-homoserine sulfhydrylase, ΓΟ-succinyl-L-homoserine sulfhydrylase, rO-acetyl-L-homoserine sulfhydrylase and ΓΟ- sulfate-L- homoserine sulfhydrylase.

[0044] Most preferably, the enzyme associated with the derivative of L-homoserine is O-acetyl-L-homoserine sulfhydrylase.

[0045] These so-called enzymes function as well known to the skilled person in the presence of a cofactor such as pyridoxal-5'-phosphate.

[0046] The enzyme and its cofactor associated are generally dissolved in water before being added to the reaction medium. The amount of enzyme relative to the weight of the compound of formula (II) is between 0.1 and 10% by weight, preferably between 1 and 5% by weight, and the amount of cofactor to the compound of formula (II) is between 0.1 and 10% by weight, preferably between 0.5 and 5% by weight.

[0047] According to a preferred embodiment of the invention, the derivative of L-serine is O-acetyl-L-serine, inorganic polysulfide is sodium polysulfide. and the enzyme used is O-acetyl-L-serine sulfhydrylase.

[0048] According to a preferred embodiment of the invention, the organic polysulfide obtained by the process is the polysulfide dicystéine.

[0049] According to another preferred embodiment of the invention, the derivative of L-homoserine is ΓΟ-acetyl-L-homoserine, inorganic polysulfide is sodium polysulfide and the enzyme used is ΓΟ-acetyl-L -homosérine sulfhydrylase.

[0050] According to a preferred embodiment of the invention, the organic polysulfide obtained by the process is the polysulfide dihomocystéine.

[0051] Regarding the pH conditions, temperatures, synthetic medium, one can refer to those described in WO2008013432 and WO2013029690 applications.

[0052] Thus, according to the operating range of the enzyme, the reaction pH is between 5 and 8, preferably between 6 and 7.5, more particularly between 6.2 and 7.2. In any case, the pH must be regulated according to the optimum functioning of the enzyme. The pH can be regulated by addition of basic inorganic polysulphide, dilute sulfuric acid or dilute ammonia.

[0053] Thus, according to the operating range of the enzyme, the temperature during the reaction is between 10 and 45 ° C, preferably between 20 and 40 ° C, more particularly between 25 and 37 ° C.

[0054] The reaction proceeds in aqueous medium or in the presence of organic solvents if they are compatible with the enzymes used. Preferably, the reaction takes place in aqueous medium.

[0055] The reaction may be conducted in batch, semi-continuously or continuously. Any type of reactor known to the skilled person, may be suitable for such reactions.

[0056] According to one embodiment of the invention, the separation and isolation of the resulting organic polysulfide may be performed according to any technique known to those skilled in the art, in particular by precipitation and filtration.

[0057] Step f / optional process according to the invention allows to obtain additional and different functions from those obtained after step d / or step e /.

[0058] Indeed, the functionalized organic polysulfide of formula (I) obtained at the end of step d / may again be functionalized at this stage f /. For example, if X-R2 represents a carboxylic function, it can be esterified, reduced aldehyde, reduced to the alcohol and then etherified, amidated, or other nitrilée. All functions can be obtained by the skilled person depending on the final use which is intended to organic polysulfide.

[0059] Thus, the organic polysulfide functionalized of formula (I) obtained at the end of step d / may be subjected to one or more additional chemical reactions to obtain one or more organic polysulphides with different functions, said reactions all being chemical reactions known to those skilled in the art.

[0060] The functionalized organic polysulphides of formula (I) obtained by the process according to the invention can be used in many applications such as lubrication, vulcanization, the sulfurization catalysts in the field of therapy, and others.

[0061] In particular, the functionalized polysulfides of formula (I) can be used as an anti-wear, extreme pressure agent or anti-oxidant. They can also enter into the composition of lubricant formulations or certain medications such as anti-radiation drugs. Finally, they can be used in the manufacture of cement, concrete or bitumen.

Examples

[0062] The following examples illustrate the present invention but are by no means limiting.

Example 1: Synthesis of tetrasulfide dihomocystéine

Step 1 :

[0063] The O-acetyl-L-homoserine was synthesized from L-homoserine and acetic anhydride according Sadamu Nagai, "Synthesis of O-acetyl-L-homoserine", Academic Press, (1971), vol .17, p. 423-424.

2nd step :

[0064] In parallel, in a glass reactor of 250 ml are introduced January 1, 21 g of sodium sulhydrate (200 mmol) in 100 mL of distilled water which is allowed to dissolve with stirring at room temperature with a thermostated oil bath. Is gradually added during 2 hours, 9.62 g of sulfur flowers (300 mmol), the solution becomes red and h S begins to degas the reaction medium. This reactor was connected to a trap containing 200 g of sodium hydroxide to 10% by mass (500mmol NaOH 100%). This sodium hydroxide solution can trap the S h from the reactor and can also track the progress of the reaction with the samples analyzed by potentiometry Argentometric. A low flow of nitrogen is introduced into the reactor so as to facilitate the departure of the H2S. After 2 hours, the analysis of the trap shows that 100% of the theoretically h S product was trapped in the soda to form sodium sulphide. Once this saturated trap (soda fully converted) after several syntheses of sodium polysulphides, sodium hydrosulphide solution can be used as such for the synthesis of these polysulphides. In the main reactor, one obtains a 1 17.1 g Na2S solution 4 assaying 14.9% by weight.

Step 3:

[0065] In a thermostated glass reactor of 250 ml, are introduced 10 g (62 mmol) of O-acetyl-L-homoserine (OAHS from Step 1) in 140 mL of distilled water. The solution was heated at 35 ° C with mechanical stirring. The pH of the reaction medium is 4.8. Is desired, prior to the enzyme, the pH was equal to 6.5; to this was added a few drops of the sodium polysulfide solution obtained in step 2. a sample is taken (t = 0) 1 mL of the reaction medium.

[0066] Prepare a 10 mL distilled water solution containing 400 μί a pyridoxal-5'-phosphate solution (10 mmol / L) and 0.6 g of enzyme (O-acetyl-L- homoserine sulfhydrylase) then this solution was added to the reactor. The reaction begins. The pH decreases and in order to maintain the reaction medium at a pH equal to 6.5, sodium tetrasulfide solution is slowly added via the dropping funnel (in total, 36.2 g (5.4 g Na2S 4 expressed as 100% - 31 mmol) of the solution obtained in step 2). Samples (1 ml) are carried out during the reaction. Analyzes by potentiometry, TLC, HPLC and UPLC / UV-mass show a gradual disappearance

reagents (OAHS and Na 2 S 4 ) and the gradual appearance in amounts more and more important compounds of the following (note that some of these polysulfides precipitates during the reaction):

Dihomocystéine disulfide (homocystine)

Tétrasulfure the dihomocystéine

[0067] The only other product observed after the total disappearance of the OAHS are traces of dihomocystéine (hydrolysis OAHS) and trace amounts of homocysteine. We can therefore conclude that the synthesis of polysulfide (mean sulfur 4) of dihomosérine from OAHS was almost total.

Step 4: Separation and isolation of polysulfide dihomocystéine:

[0068] The reaction medium of step 3 is filtered a first time to recover, after drying, 4.4 g of polysulfide dihomocystéine. The residual solution is concentrated by partial evaporation of the water (so as to avoid precipitation of sodium acetate present in the reaction medium) under reduced pressure at 30 ° C, a new precipitate formed. After filtration and drying, 3.8 g again sulfide dihomocystéine. Overall isolated yield polysulfide homoserine is 8.2 g of 10.30 g theoretical 79.6%. Further analysis of this dry product

showed that this solid contained 41% (elemental analysis) of sulfur (and hence an average rank of 4.3) and does not contain elemental sulfur in the free state (HPLC analysis).

Example 2: Synthesis of tetrasulfide dihomocystéine (without enzyme or co-enzyme)

[0069] Example 1 was repeated with the only difference that the pyridoxal-5'-phosphate and enzyme solution (10 mL distilled water containing 400 μΙ_ a pyridoxal-5'-phosphate solution ( 10 mmol / L) and 0.6 g of enzyme (O-acetyl-L-homoserine sulfhydrylase) was not added into the reactor. It turns out that the reaction does not start and there is no continuously adding the sodium polysulfide solution seeking to maintain a pH of 6.5. by increasing to a pH of 8 by addition of sodium polysulfide solution, the only reaction observed is the beginning of hydrolysis 'OAHS homoserine. this example shows that this synthesis needs to be catalyzed by an enzyme to perform.

Example 3: Synthesis of cysteine ​​disulfide (cystine)

Step 1 :

[0070] The O-acetyl-L-serine is commercially available from Sigma-Aldrich. It can also be synthesized by any means known in the art from L-serine.

2nd step :

[0071] In a glass reactor of 250 mL are introduced January 1, 21 g of sodium hydrosulfide (200 mmol) in 100 ml of distilled water which is allowed to dissolve with stirring at room temperature through a bath oil thermostatically. Is gradually added during 2 hours, 3.2 g of sulfur flowers (100 mmol), the solution becomes bright yellow and h S begins to degas the reaction medium. This reactor was connected to a trap containing 200 mL of a 10 wt% solution of sodium hydroxide (500 mmol NaOH 100%). This sodium hydroxide solution can trap the S h from the reactor and to follow the progress of the reaction with the samples analyzed by potentiometry Argentometric. A low flow of nitrogen is introduced into the reactor so as to facilitate the departure of the h S. After 2 hours, the analysis of the trap shows that 100% of the theoretically h S product was trapped in the soda to form sodium sulphide. Once this saturated trap (soda fully converted) and after synthesis of sodium disulfide, sodium hydrosulphide solution can be used as such for the synthesis of this disulfide. In the reactor there is obtained 1 1 1 g of a solution of Na 2 S 4 titrating 9.9% by weight.

Step 3:

[0072] In a thermostated glass reactor of 250 mL, were introduced 9.12 g (62 mmol) of O-acetyl-L-serine in 140 ml of distilled water. The solution was heated at 35 ° C with mechanical stirring. The pH of the reaction medium is 4.6. Is desired, prior to the enzyme, the pH was 6.5; to this was added a few drops of the sodium disulfide solution (Na2S2) obtained in step 2. a sample is taken (t = 0) 1 mL of the reaction medium. A solution of pyridoxal-5'-phosphate (10 mmol, 0.4 mL) and the enzyme, sulfhydrylase O-acetyl-L-serine (0.6 mL) are dissolved in 10 mL of water and then added in the reactor. The reaction begins. The pH decreases and in order to maintain the reaction medium at a pH equal to 6.5, the sodium disulfide solution was added slowly via the dropping funnel (in whole is added 32 g of the solution obtained in step 2 3.2 g Na2S2 expressed as 100%, 31 mmol). Samples (1 ml) are carried out during the reaction. Analyzes by potentiometry, TLC, HPLC and UPLC / UV-mass show a gradual disappearance of the reagents (O-acetyl-L-serine and Na2S2) and the gradual appearance of cystine. There is also the appearance of a precipitate resulting from the formation of cystine:

[0073] The only other product observed after the complete disappearance of the O-acetyl-L-serine are traces of serine (hydrolysis ΓΟ-acetyl-L-serine). We can therefore conclude that the synthesis of cystine from O-acetyl-L-serine was almost total.

Step 4: Separation and isolation of cystine:

[0074] The reaction medium of step 3 is filtered a first time to recover, after drying, 4.7 g of cystine. The residual solution is concentrated by partial evaporation of the water (so as to avoid precipitation of sodium acetate present in the reaction medium) under reduced pressure at 30 ° C, and a new precipitate formed. After filtration and drying, again 1, 2 g of cystine. The total isolated yield is 5.74 g cystine of 7.44 g theoretical 77.2%. Further analysis of this dry product showed that this solid contained 26.82% (elemental analysis) of sulfur (so an average rank of 2.01) and does not contain elemental sulfur in the free state (analysis HPLC).

CLAIMS
1. A method for synthesizing at least one functionalized organic polysulfide of formula (I):
R 2 -X- (R7) C * H- (CH2) n-Sa- (CH2) NC * H (R 7 ) -X-R2 (I)

in which

- R and R 7 , or not different, are hydrogen or a hydrocarbon chain branched or unbranched, saturated or unsaturated, linear or cyclic, aromatic or not, of 1 to 20 carbon atoms, which may contain heteroatoms;

- X is -C (= 0) - or -CH 2 -, or -CN;

- R2 is (i) zero (when X is -CN), (ii) hydrogen, (iii) -OR3, wherein R3 is hydrogen or a branched hydrocarbon chain or unsubstituted, saturated or unsaturated, linear or cyclic, aromatic or not, of 1 to 20 carbon atoms which can comprise heteroatoms, or (iv) NR4R5, R 4 and R 5 , or not different, being hydrogen or a branched hydrocarbon chain or unsubstituted, saturated or unsaturated, linear or cyclic, aromatic or not, of 1 to 20 carbon atoms, which may contain heteroatoms;

- n is 1 or 2;

- a is an integer or decimal number between 2 and 10, preferably between 2 and 6; and

- * represents an asymmetric carbon;

said method comprising the steps of:

a / providing at least one compound of formula (II):

G- (CH 2 ) NC * H (R 7 ) -X-R2 (II)

in which

- n, R, R 2 , R 7, X and * are as defined above,

- G represents either (i) R 6 -C (= 0) -0-, or (ii) (R 8 0) (R 9 0) -P (= 0) -0-, or (iii) R 8 0 -S0 2 -0-;

- R6 is hydrogen or a branched hydrocarbon chain or unsubstituted, saturated or unsaturated, linear or cyclic, aromatic or not, of 1 to 20 carbon atoms, which may contain heteroatoms;

- Re and Rg, identical or different, being a proton H, alkali, alkaline earth or ammonium, preferably a proton H or an alkali, and more particularly to a proton H or Na;

b / providing at least one inorganic polysulphide;

cl reaction between said at least one compound of formula (II) and said at least inorganic polysulphide in the presence of at least one enzyme selected from sulfhydrylases, and preferably a sulfhydrylase associated with said compound of formula (II);

61 obtaining at least one functionalized organic polysulfide of formula (I);

e / separating and isolating said at least functionalized organic polysulfide of formula (I) and;

f / optionally, further functionalization of the functionalized organic polysulfide of formula (I) obtained in step d / or e /;

al steps and b / is or not performed simultaneously.

2. The method of claim 1, wherein the functionalized organic polysulfide of formula (I) is enantiomerically pure.

3. A method according to one of the preceding claims, wherein the functionalized organic polysulfide of formula (I) is selected from polysulfide and sulfide dicystéine dihomocystéine.

4. Method according to one of the preceding claims, wherein the compound of formula (II) is selected from the derivatives of L-serine and the derivatives of L-homoserine.

5. The method of claim 4, wherein the derivative of L-serine is selected from O-phospho-L-serine, ΓΟ-succinyl-L-serine, ΓΟ-acetyl-L-serine, O- acetoacetyl-L-serine, ΓΟ-propio-L-serine, ΓΟ-coumaroyl-L-serine, O-malonyl-L-serine, O-hydroxy-methylglutaryl-L-serine, L- ΓΟ-pimelyl serine and ΓΟ-sulfato-L-serine, preferably O-phospho-L-serine, ΓΟ-succinyl-L-serine, ΓΟ-acetyl-L-serine and O-sulfato-L-serine, and particularly O-acetyl-L-serine.

6. The method of claim 4, wherein the derivative of L-homoserine is selected from ΓΟ-phospho-L-homoserine, O-succinyl-L-homoserine, O-acetyl-L-homoserine, the O-acetoacetyl-L-homoserine, propio-L-homoserine, O-coumaroyl-L-homoserine, O-malonyl-L-homoserine, O-hydroxymethylglutaryl-L-homoserine, O-pimelyl - L-homoserine and ΓΟ-sulfato-L-homoserine, preferably, O-succinyl-L-homoserine, O-acetyl-L-homoserine, O-phospho-homoserine and ΓΟ-sulfato-L homoserine, more particularly O-acetyl-L-homoserine.

7. Method according to one of the preceding claims, wherein the sulfhydrylase is selected from sulfhydrylases associated with derivatives of L-serine and sylfhydrylases associated with derivatives of L-homoserine.

8. The method of claim 7, wherein the sulfhydrylase associated with the derivative of L-serine is selected from sulfhydrylase ΓΟ-phospho-L-serine sulfhydrylase ΓΟ-succinyl-L-serine sulfhydrylase ΓΟ-acetyl-L-serine, sulfhydrylase the acetoacetyl-L-serine sulfhydrylase ΓΟ-propio-L-serine sulfhydrylase ΓΟ-coumaroyl-L-serine, O-malonyl-L-serine sulfhydrylase, sulfhydrylase ΓΟ-hydroxymethylglutaryl-L-serine, O -pimélyl- sulfhydrylase L-serine and ΓΟ-sulfato-L-serine, preferably ΓΟ-phospho-L-serine sulfhydrylase ΓΟ-succinyl-L-serine sulfhydrylase ΓΟ-acetyl-L-serine and O-sulfato L-serine, especially sulfhydrylase ΓΟ-acetyl-L-serine.

9. The method of claim 7, wherein the sulfhydrylase associated with the derivative of L-homoserine is selected from ΓΟ-phospho-L-homoserine sulfhydrylase, rO-succinyl-L-homoserine sulfhydrylase, ΓΟ-acetyl-L-homoserine sulfhydrylase, rO-acetoacetyl-L-homoserine sulfhydrylase, ΓΟ-propio-L-homoserine sulfhydrylase, rO-coumaroyl-L-homoserine sulfhydrylase, ΓΟ-malonyl-L-homoserine sulfhydrylase, rO-hydroxymethylglutaryl-L-homoserine sulfhydrylase, ΓΟ-pimelyl L -homosérine sulfhydrylase and ΓΟ-sulfato-L-homoserine sulfhydrylase, preferably O-phospho-L-homoserine sulfhydrylase, ΓΟ-succinyl-L-homoserine sulfhydrylase, the O-acetyl-L-homoserine sulfhydrylase and ΓΟ-sulfato L-homoserine sulfhydrylase, especially ΓΟ-acetyl-L-homoserine sulfhydrylase.

10. A method according to any preceding claim, wherein the inorganic polysulphide is selected from alkali metal polysulfides, alkaline earth metal and ammonium, preferably the sodium polysulfide, potassium polysulfide, lime sulfur and ammonium polysulfide and especially sodium polysulfide.

11. A method according to any preceding claim, having an f / optional step of further functionalization of the functionalized organic polysulfide of formula (I) obtained in step d / or e / step.

12. Organic Polysulfide functionalized of formula (I) prepared according to the method described in claims 1 to 1 of 1.

13. Polyphenylene dicystéine or dihomocystéine prepared according to the method described in claims 1 to 1 of 1.

14. Use of the functionalized organic polysulfide of formula (I) prepared according to the method of claims 1-1 1 for lubrication, vulcanization, the sulphurization of the catalysts, the preparation of medicaments.