A process for purifying one or more cosmetic ingredients comprising a purification step with at least one cationic ion exchange resin and at least one electrodialysis step

Abstract

The present invention relates to a purification (PU) process for one or more cosmetic ingredients, in particular one or more C-glycoside derivatives corresponding to formula (I), as described below, preferably corresponding to formula (I') or (I''), and their optical isomers, geometric isomers, and / or their solvates such as hydrates, comprising at least one purification step carried out with at least one cationic ion exchange resin and at least one electrodialysis step. The invention also relates to a process for preparing one or more C-glycoside derivatives corresponding to formula (I), as described below, preferably corresponding to formula (I') or (I''), and their optical isomers, geometric isomers, and / or their solvates such as hydrates, comprising at least one purification step carried out with at least one cationic ion exchange resin and at least one electrodialysis step.

Description

Title of the invention: Process for purifying one or more cosmetic ingredients comprising a purification step with at least one cationic ion exchange resin and at least one electrodialysis

[0001] The present invention relates to a purification process (PU) of one or more cosmetic ingredients, in particular one or more C-glycoside derivatives corresponding to formula (I), as described below, preferably corresponding to formula (!') or (I”), and their optical isomers, geometric isomers, and / or their solvates such as hydrates, comprising at least one purification step carried out with at least one cationic ion exchange resin and at least one electrodialysis.

[0002] The invention also relates to a process for preparing one or more cosmetic ingredients, in particular one or more C-glycoside derivatives corresponding to formula (I), as described below, preferably corresponding to formula (!') or (I”), and their optical isomers, geometric isomers, and / or their solvates such as hydrates, comprising at least one purification step carried out with at least one cationic ion exchange resin and at least one electrodialysis.

[0003] The invention also relates to a process for purifying at least one reaction medium including at least one C-glycoside derivative corresponding to formula (I) and at least one salt of formula (IV), as described below.

[0004] The processes for synthesizing active ingredients, organic and soluble in water, with interesting cosmetic properties can lead to the formation of impurities, found in an ionic form, which most often prove to be tedious to minimize, or even to eliminate, without having a more or less significant impact on the yield of the final cosmetic active compound.

[0005] Furthermore, such impurities, when present with the final cosmetic active compound, can generate a color, a change in texture or an odor that is not desired in the cosmetic compositions using said active ingredient. Thus, such impurities can be the cause of an unpleasant and marked odor, for example a pungent and strongly vinegary odor, likely to appear, even after the implementation of several purification operations, and to prove unpleasant and persistent even after formulation for consumers, especially since the current trend is to use fewer and fewer perfumes in cosmetic products to mask or neutralize this type of odor.

[0006] Such impurities can also cause compatibility problems with other additives possibly present in cosmetic formulations. finals.

[0007] Such impurities can also be acid or base salts which will have an effect on the pH in an aqueous medium. This effect is all the more troublesome when the cosmetic active ingredient is isolated in the form of a concentrated aqueous solution.

[0008] Furthermore, the presence of such impurities, in particular inorganic and / or organic salts, can induce a significant increase in the viscosity of the aqueous reaction medium comprising the cosmetic active ingredient(s), thus making it difficult, in certain cases, to obtain concentrated solutions of cosmetic active ingredients intended for formulation.

[0009] For example, C-glycoside derivatives are organic compounds, soluble in water, whose properties are generally of interest in the field of cosmetics, in particular in care compositions, in order to be used to stimulate the synthesis of glycosaminoglycans present in the dermis and in particular to provide density and firmness to the skin (see for example the scientific article entitled in English: Synthesis of Pro-XylaneTM: A new bio-logically active C-glycoside in aqueous media, M. Dalko-Csiba et al., Bioorganic & Medicinal Chemistry Letters 19 (2009) 845-849).

[0010] C-glycoside derivatives, such as xylose C-glycoside derivatives, are generally synthesized by means of a reaction, called the Lubineau reaction (Rodrigues, F., Canac, Y. and Lubineau, A., A convenient, one-step, synthesis of [3-Cglycosidic ketones in aqueous media. - Chemical Communications - 2000, (20), 2049-2050), from an unprotected monosaccharide or polysaccharide, for example D-xylose, and a beta-dicarbonyl compound, for example acetylacetone, in an aqueous medium in the presence of alkaline agent(s).

[0011] The Lubineau reaction is carried out with at least one alkaline agent, such as sodium bicarbonate or soda, present in an equimolar or excess quantity relative to the monosaccharide or polysaccharide, preferably in excess, for a reaction time which may vary from 5 minutes to 20 hours depending on the nature of the alkaline agent and / or the reaction parameters such as the concentration and / or the temperature.

[0012] However, such a synthesis reaction presents in particular the major pitfall of leading to the formation of impurities, found in particular in the form of salts, for example in the form of an organic salt, such as sodium acetate, the residual quantities of which can prove significant and difficult to reduce even by implementing several conventional purification and / or washing operations.

[0013] At the end of this reaction, the aqueous reaction medium can be neutralized with at least one acidifying agent, in particular mineral, for example hydrochloric acid, to convert the organic acid salt into organic acid, in particular by transforming sodium acetate to acetic acid, and then reducing the amounts of organic acid to commercially acceptable levels.

[0014] However, the neutralization of the reaction medium with at least one mineral acidifying agent, such as hydrochloric acid, also leads to the formation of salts, in particular sodium chloride, which can be eliminated by precipitation thanks to the addition of water-miscible solvents such as alcohols, in particular isobutanol or ethanol.

[0015] It is known from the prior art to add at the end of the reaction a water-immiscible solvent to wash the aqueous reaction medium and then to pass the aqueous medium over a previously conditioned acid resin before concentrating in the presence of alcohol. To do this, successive distillation operations to remove the water in particular, then the addition of alcohol can cause crystallization of salts, followed by possible washing(s), carried out with several cycles of adding water, to reduce the quantity of salts to acceptable levels within commercial solutions intended to be used in the cosmetic field.

[0016] At the end of these different purification operations, the C-glycoside derivatives obtained can be pure without solvent and then undergo, in certain cases, a hydrogenation reaction aimed at reducing the ketone function of the C-glycoside derivative and resulting from the beta-dicarbonyl derivative, into a hydroxyl function.

[0017] In particular, C-glycoside derivatives of xylose, such as C-beta-D-xylopyranoside-n-propan-2-one, may subsequently undergo a reduction reaction to yield C-beta-D-xylopyranoside-2-hydroxy-propane.

[0018] However, such purification operations, including those carried out several times in succession, have not made it possible to satisfactorily reduce the impurities generated during the process of preparing C-glycoside derivatives, particularly on an industrial scale.

[0019] Indeed, such purification operations have the disadvantage of having to be carried out several times to sufficiently reduce the impurity contents in a satisfactory manner and, when the impurities are malodorous, to minimize the odors generated by certain impurities such as acetic acid which are unpleasant and should be avoided for cosmetic use. In addition, the formation of sodium chloride, during the neutralization step, requires the implementation of washing operations carried out with the addition of water, organic solvents, in particular alcohols, and possibly distillation in order to be properly eliminated.

[0020] Such purification operations, especially repeated ones, thus have the disadvantage of reducing the yield, generating additional organic effluents, increasing the number of stages and / or being tedious to implement on an industrial level, both to reduce the organic acid content, in particular organic acid acetic acid, as well as to reduce the salt content, for example sodium chloride, in the final cosmetic active ingredient intended for the formulation of cosmetic products.

[0021] Furthermore, the use of organic solvents, in particular (a)polar aprotic organic solvents, during washing operations often has the disadvantage of not sufficiently reducing impurities and of inducing the implementation of additional washing or neutralization operations, or even purification by chromatography and / or crystallization, which may further impair the yield. Such additional operations are tedious to implement on an industrial scale. In addition, residual contents of organic solvent(s) may persist in the solutions of cosmetic active ingredients used in the final cosmetic formulations, which is not desirable.

[0022] Furthermore, disadvantages similar to those described above are also found when it is desired to reduce, or even minimize, the salt content in aqueous formulations based on cosmetic ingredients, in particular one or more C-glycoside derivatives.

[0023] As a result, the washing and / or purification operations conventionally implemented to reduce the salt content in media comprising at least one C-glycoside derivative do not lead to satisfactory results, particularly in terms of yield and degree of purity, in particular for industrial-scale, reproducible and robust manufacturing, for use in the field of cosmetics.

[0024] In view of the above, there is therefore a real need to implement a new method for purifying at least one aqueous medium comprising at least one cosmetic ingredient and in particular at least one C-glycoside derivative and at least one salt, which does not have the drawbacks mentioned above, leading in particular to an improved degree of purity, a higher yield and the implementation of which is more optimized, specifically on an industrial level, in terms of product quality on an industrial scale, number of purification steps, implementation and / or organic effluents generated.

[0025] There is also a real need to implement a new process for the preparation of C-glycoside derivatives, which does not have the drawbacks mentioned above, leading in particular to an improved degree of purity, a higher yield and the implementation of which is more optimized, specifically on an industrial level, in terms of product quality on an industrial scale, number of purification steps, implementation and / or organic effluents generated.

[0026] In other words, one of the aims of the present invention is in particular to propose a process for the preparation of one or more C-glycoside derivatives, during which the impurities are minimized in order to be able to be efficiently implemented on a large scale. industrial for cosmetic applications.

[0027] In particular, one of the aims of the present invention is to provide a process for preparing one or more C-glycoside derivatives during which the impurities, including those likely to generate an unpleasant or unpleasant odor, for example a pungent and strongly vinegary odor, in particular resulting from the synthesis step, are minimized in order to be able to be effectively implemented on an industrial scale for cosmetic applications.

[0028] The present invention therefore relates in particular to a process for preparing at least one compound of the following formula (I): (I)

[0029] Formula (I) in which: - SA' represents a monosaccharide group or a polysaccharide group comprising up to 20 sugar units, in particular up to 6 sugar units, preferably a monosaccharide, disaccharide or trisaccharide, more preferably a monosaccharide, in pyranose and / or furanose form and of L and / or D series, said monosaccharide group or polysaccharide group being substituted by at least one free hydroxy group, and optionally at least one amine group optionally protected in particular by an acetyl group R'-C(Y)- with R' representing a hydrogen atom, or a (Ci-C6)alkyl group such as methyl, and Y represents O, S, preferably O, - the bond between SA' and CH2-X is a C-anomeric bond, - R represents a hydrogen atom, a C1-C10 alkyl group, preferably C1-C4, such as methyl, or an alkyl(C1-C4)carbonyl group such as acetyl, preferably a hydrogen atom; - Ri represents a hydrocarbon chain, saturated or unsaturated, linear or branched, cyclic or acyclic, preferably acyclic, in C1-C10, preferably in C1-C4, more preferably saturated,

[0030] as well as one of its optical isomers, geometric isomers, and / or one of its solvates such as hydrates;

[0031] said method comprising: - at least one reaction step (i) taking place according to the following synthesis scheme (A):

[0032]

[0033]

[0034] SA' 4- .U $$ (W 0À) tW synthesis route (A) in which: • Ri and R2 are the same or different; with R2 having the same meaning as Ri in formula (I), • SA' has the same meaning as in formula (I), • D+ is an organic or inorganic cation from the alkaline agent, preferably D+ is an inorganic cation, said reaction step (i) being carried out in aqueous media in the presence of: • at least one compound of formula (II), • at least one compound of formula (III), and • at least one alkaline agent in an equimolar or excess quantity, relative to the compound of formula (II), preferably in excess, to lead to the formation of at least one compound of formula (IA) and at least one compound of formula (IV) in an aqueous medium; - optionally, at least one reaction step (ii) of at least said compound of formula (IA) in a preferably aqueous medium to lead to the formation of at least one compound corresponding to the following formula (IB): HRH T GOLD (IB) Formula (IB) in which: - SA', Ri and R have the same meanings as in formula (I); - at least one purification (P) of the reaction medium including at least said compound of formula (IV), carried out in an aqueous medium, comprising: • at least one treatment step (PI), carried out with at least one cationic ion exchange resin, in the aqueous reaction medium resulting from the reaction step(s) (i), • at least one electrodialysis step (P2) of said aqueous reaction medium comprising at least said compound of formula (IA) and at least the compound of formula (IV); said electrodialysis step(s) (P2) preferably being carried out after the said processing steps (PI).

[0035] By "bond between SA' and CH2-X" which "is a bond of C-anomeric nature" is meant that the part of the sugar unit SA' is connected to the rest of the molecule via the methylene group -CH2- by a carbon-carbon bond CC (i.e. carbon of the sugar SA'-carbon of the methylene -CH2-) and not by an oxygen-carbon bond OC (i.e. not by an oxygen bond of the sugar SA' - carbon of the methylene -CH2-).

[0036] For the purposes of the present invention, SA' comprises a monosaccharide or polysaccharide SA group comprising up to 20 sugar units, as defined above; SA being substituted by at least one free hydroxy group.

[0037] In other words, SA' has the same meaning as SA and comprises at least one free hydroxy group (-OH).

[0038] For the purposes of the present invention, a compound of formula (IA) is a compound of formula (I) in which X corresponds to a divalent radical -C(O)-.

[0039] For the purposes of the present invention, a compound of formula (IB) is a compound of formula (I) in which X corresponds to a divalent radical -CH(OR)- with R as defined above, preferably R represents a hydrogen atom.

[0040] In other words, the invention relates to a process for preparing one or more C-glycoside derivatives of formula (I), as described above, comprising at least one treatment step (PI) and one electrodialysis step (P2), as defined above, carried out in an aqueous medium and intended to minimize at least significantly the contents of ionic impurities of formula (IV) resulting from the synthesis step (i); said electrodialysis step(s) (P2) preferably being carried out after said treatment step(s) (PI).

[0041] Thus the purification step (P) has the advantage of being flexible to implement during the preparation of at least one compound of formula (I).

[0042] Indeed, the purification step (P) can be carried out at least once between the reaction step (i) and the reaction step (ii) and / or after at least one reaction step (ii).

[0043] According to one embodiment, the purification step (P) is carried out at least once at the end of the reaction step(s) (i).

[0044] According to another embodiment, the purification step (P) is carried out at least once at the end of the reaction step(s) (ii).

[0045] According to a particular embodiment, the purification step (P) is carried out at least once at the end of step(s) (i) and the method of the invention does not include step ii).

[0046] According to another embodiment, the method of the invention comprises at least one step i), preferably one step i), and at least one step ii), preferably one step ii), and the purification step (P) is carried out at least once at the end of at least one step (i) without being carried out at the end of the step(s) (ii).

[0047] According to yet another embodiment, the method of the invention comprises at least one step i), preferably one step i), and at least one step ii), preferably one step ii), and the purification step (P) is carried out at least once at the end of at least one step (ii) without being carried out at the end of the step(s) (i).

[0048] According to another embodiment, the method of the invention comprises at least one step i), preferably one step i), and at least one step ii), preferably one step ii), and the purification step (P) is carried out at least once at the end of at least one step (i) and at least once at the end of at least one step (ii).

[0049] According to a preferred embodiment, the method of the invention comprises a step i), and a step ii), and the purification step (P) is carried out at least once at the end of step (i) without being carried out at the end of step(s) (ii).

[0050] The method according to the invention thus makes it possible to achieve the objectives as described above, that is to say that it leads to one or more cosmetic ingredients, in particular one or more compounds of formula (I), having a high degree of purity with a satisfactory yield while presenting an industrially optimized implementation, in particular robust and reproducible, in particular compared to the methods conventionally implemented in the prior art.

[0051] In particular, the method according to the invention has the advantage of minimizing impurities, including those usually causing a marked and unpleasant odor, such as a pungent and strongly vinegary odor, which are particularly difficult to eliminate in the methods conventionally implemented in the prior art.

[0052] The process according to the invention has the advantage of being carried out in an aqueous medium preferably free of organic solvent to reduce the impurities resulting from the reaction step(s) (i), which greatly improves its environmental footprint while being easy to implement on an industrial level.

[0053] The method according to the invention then advantageously makes it possible to reduce the quantities of perfumes to be used to mask or neutralize odors likely to be unpleasant during the preparation of a cosmetic formulation using one or more cosmetic ingredients, in particular at least one compound of formula (I).

[0054] The process according to the invention also makes it possible to reduce the organic effluents at the reactor outlet and to limit the numerous washing operations conventionally implemented in the processes described in the prior art.

[0055] The process according to the invention notably presents an implementation that is easier to optimize on an industrial level than the conventional processes of the prior art, notably those involving a successive implementation of several operations to reduce impurities as much as possible, which makes it possible to treat the synthesis reaction and the purification in the same reactor having a suitable format.

[0056] The method according to the invention makes it possible to do without the implementation of additional purification steps carried out by chromatography and / or crystallization, which are not suitable on an industrial level and / or which are likely to harm the yield.

[0057] The process according to the invention thus makes it possible to achieve a gain in the number of purification steps to be implemented at the end of the synthesis reaction i) and / or ii) to reduce the impurity content of the cosmetic ingredient, in particular of the compound (I).

[0058] Furthermore, when the process according to the invention implements a reduction step ii), carrying out at least one purification step (P) at the end of step i) prior to ii) greatly facilitates the obtaining of compounds of formula (I) with X = -CH(OR)- with a very good yield and very good purity.

[0059] The method according to the invention also has the advantage of easily controlling target levels of impurities, which allows several grades of a compound of formula (I) to be obtained, depending on the desired content of impurities.

[0060] The method according to the invention thus makes it easier to control the impurity contents.

[0061] The invention also relates to a purification process (PU) of at least one aqueous medium comprising at least one cosmetic ingredient, and at least one salt; said process (PU) comprising the use of at least one cationic ion exchange resin (PI) and at least one electrodialysis (P2).

[0062] The electrodialysis(s) (P2) is or are preferably carried out after the cationic ion exchange resin(s) (PI).

[0063] The present invention thus relates in particular to a purification process (PU) of at least one aqueous medium comprising: - at least one cosmetic ingredient, in particular at least one compound of formula (I), as defined above, - at least one salt;

[0064] said method (PU) comprising at least one treatment step (PI) of said aqueous medium, carried out with at least one cationic ion exchange resin, and at least one electrodialysis step (P2) of said aqueous medium; said electrodialysis step(s) (P2) preferably being carried out after said treatment step(s) (PI).

[0065] The purification process (PU) according to the invention thus makes it possible to effectively reduce the quantity of salt(s) and / or the conjugated acid form(s) of said salts found in a mixture with at least one cosmetic ingredient and in particular at least one compound of formula (I) in an aqueous medium.

[0066] The salt(s) may be derived from at least one step of preparation of said ingredient cosmetic and / or be derived from one or more washing operations and / or one or more neutralization operations carried out after at least one of the steps of a process for preparing said cosmetic ingredient(s).

[0067] The purification process (PU) according to the invention thus makes it possible to effectively reduce the quantity of salt(s) found in a mixture with at least one cosmetic ingredient, in particular at least one compound of formula (I) in an aqueous medium.

[0068] The salt(s) may be derived from at least one step of preparation of said cosmetic ingredient and / or be derived from one or more washing operations and / or one or more neutralization operations carried out after at least one of the steps of a process for preparation of said cosmetic ingredient.

[0069] The salt(s) present in the aqueous medium may be derived from at least one of the steps of a process for preparing at least one cosmetic ingredient and in particular at least one compound of formula (I) and / or be derived from one or more washing operations and / or one or more neutralization operations carried out after at least one of the steps of a process for preparing a cosmetic ingredient and in particular a process for preparing the compound of formula (I).

[0070] The salt(s) present in the aqueous medium may also result from an addition to said aqueous medium. These include in particular mineral acids such as hydrogen halides, in particular hydrochloric acid, sulfonic acids, and carboxylic acids such as acetic acid.

[0071] In other words, the purification process (PU) according to the invention makes it possible to treat any aqueous medium comprising at least one cosmetic ingredient and at least one compound of formula (I) and at least one salt, which may or may not be an impurity, with a view to at least one cosmetic use, preferably for the care of keratin materials, such as the skin.

[0072] The purification process (PU) makes it possible to advantageously reduce the presence of at least one salt, which may or may not be an impurity, in an aqueous medium without significantly impacting the quality and / or the degree of purity of the cosmetic ingredient.

[0073] The purification process (PU) makes it possible to advantageously reduce the presence of at least one salt, which may or may not be an impurity, in an aqueous medium without significantly impacting the quality and / or the degree of purity of a compound of formula (I).

[0074] The purification process (PU) makes it possible in particular to significantly reduce the content of one or more ionic impurities, including those causing an unpleasant odor, found in a mixture with at least one compound of formula (I) in an aqueous medium.

[0075] The purification process (PU) further facilitates the preparation of solutions com commercial, based on at least one cosmetic ingredient and in particular at least one compound of formula (I), intended for at least one cosmetic use, preferably for the care of keratin materials, such as the skin.

[0076] The purification process (PU) according to the invention can be carried out after one or more steps of synthesis of at least one cosmetic ingredient and in particular at least one compound of formula (I) and / or after at least one step of washing and / or neutralization of an aqueous reaction medium comprising at least said compound of formula (I).

[0077] The purification process (PU) according to the invention can thus be implemented during a process for preparing one or more cosmetic ingredients preferably chosen from the compounds of formula (I), for example at the end of the preparation process or after one of the steps of the process, for example between one of the steps of the process.

[0078] Another object of the present invention is further to provide a preparation process (PR) of one or more cosmetic ingredients, preferably chosen from the compounds of formula (I), in an aqueous medium, comprising at least one purification (PU) comprising at least one treatment step (PI) of said aqueous medium, carried out with at least one cationic ion exchange resin, and at least one electrodialysis step (P2) of said aqueous medium; said electrodialysis step(s) (P2) preferably being carried out after said treatment step(s) (PI).

[0079] In other words, the invention relates to a preparation process (PR) of one or more cosmetic ingredient(s) preferably chosen from the compounds of formula (I), comprising at least one purification (PU) during which at least one aqueous medium comprising at least said at least one cosmetic ingredient preferably chosen from the compound(s) of formula (I) and at least one salt is subjected to at least one cationic ion exchange resin (PI) and at least one electrodialysis (P2).

[0080] In other words, the invention relates in particular to a process for the preparation (PR) of one or more cosmetic ingredients preferably chosen from the compounds of formula (I), comprising: - at least one synthesis step (PRi) of at least one cosmetic ingredient preferably chosen from at least one compound of formula (I), leading to the formation of at least said cosmetic ingredient preferably said compound of formula (I), and at least one salt in an aqueous medium, • optionally, at least one washing and / or neutralization step (PR0), preferably at least one neutralization step (PR0) of the aqueous reaction medium resulting from at least one of the steps of synthesis (PRi), - at least one purification (PU) comprising at least one treatment step (PI) of said aqueous medium, carried out with at least one cationic ion exchange resin, and at least one electrodialysis step (P2) of said aqueous medium; said electrodialysis step(s) (P2) preferably being carried out after said treatment step(s) (PI).

[0081] The preparation process (PR) according to the invention thus makes it possible to achieve the objectives as described above, that is to say that it leads to one or more cosmetic ingredients preferably chosen from the compounds of formula (I), having a high degree of purity with a satisfactory yield while presenting an industrially optimized implementation, in particular robust and reproducible, in particular compared to the processes conventionally implemented in the prior art.

[0082] In particular, the preparation process (PR) according to the invention has the advantage of minimizing impurities in ionic form, and / or their non-ionic conjugated forms, including those usually causing a marked and unpleasant odor, such as a pungent and strongly vinegary odor, which are particularly long and difficult to eliminate with conventional washing and / or purification operations.

[0083] In particular, the preparation process (PR) according to the invention has the advantage of minimizing impurities in ionic form such as their acid form, including those usually causing a marked and unpleasant odor, such as a pungent and strongly vinegary odor, which are particularly long and difficult to eliminate with conventional washing and / or purification operations.

[0084] The process (PR) according to the invention notably presents an implementation that is easier to optimize on an industrial level than the conventional processes of the prior art, notably those involving a successive implementation of several distillations to reduce as much as possible the impurities in ionic form, which makes it possible to treat the synthesis reaction as well as the purification and / or washing steps in the same reactor having a format adapted to the batch treated.

[0085] The process (PR) according to the invention also has the advantage of not using an organic solvent to reduce the impurities resulting from at least one of the synthesis steps, which improves its environmental footprint.

[0086] The preparation process (PR) according to the invention thus makes it possible to achieve a gain in the number of steps to be implemented at the end of the synthesis reaction to reduce the impurity content and facilitates, on an industrial level, the implementation of additional reactions of the cosmetic ingredient such as the additional reactions implemented in the process for preparing cosmetic ingredient(s), in particular the compound of formula (I), for example a step of reducing the compound of formula (I).

[0087] The preparation process (PR) according to the invention also has the advantage of efficiently leading to several grades of a cosmetic ingredient depending on the desired impurity content thanks to the use of electrodialysis.

[0088] Other objects, characteristics, aspects and advantages of the invention will appear even more clearly on reading the description and the example which follows.

[0089] In what follows, and unless otherwise indicated, the limits of a domain of values ​​are included in this domain, in particular in the expressions “between” and “ranging from ... to ...”.

[0090] Furthermore, the expression “at least one” used in the present description is equivalent to the expression “one or more”.

[0091] Furthermore, the expression "at least" used in the present description is equivalent to the expression "greater than or equal to". Finally, in a manner known per se, the term "Cn" or "Cn" compound or group denotes a compound or group containing "n" carbon atoms in its chemical structure.

[0092] For the purposes of the present invention, the term "cosmetic ingredient" is equivalent to "cosmetic active ingredient" and designates any compound possessing an activity of interest in the cosmetic field such as an active ingredient having a biological action after application to keratin materials such as non-therapeutic active ingredients intended to prevent or treat the signs of aging, such as moisturizers, humectants, such as active ingredients having an action on the barrier function, such as UV filters, and / or any compound modifying the appearance of keratin materials such as coloring materials.

[0093] For the purposes of the present invention, the terms “purification (P)” and “purification step (P)” are used interchangeably.

[0094] For the purposes of the present invention, the terms “alkaline agent” or “alkalizing agent” are used interchangeably.

[0095] The alkalizing agent(s) may be mineral alkaline agents, preferably chosen from the group consisting of alkali metal hydroxides or alkaline earth metal hydroxides, such as lithium hydroxides, sodium hydroxide, potassium hydroxide, alkali or alkaline earth metal (bi)carbonates such as sodium or potassium (bi)carbonates, and mixtures thereof.

[0096] The alkalizing agent(s) may be organic alkaline agents, preferably chosen from the group consisting of mono(Ci-C6)(hydroxy)alkylamine, di(Ci-C6)(hydroxy)alkylamine, tri(Ci-C6)(hydroxy)alkylamine (preferably tri(Ci-C6)(hydroxy)alkylamine), saturated or unsaturated cyclic amines, aromatic such as pyridine, or non-aromatic, optionally substituted by one or more (Ci-C4)alkyl groups such as tetrahydropyridines, optionally substituted by one or more (Ci-C4)alkyl groups, piperidines optionally substituted by one or more (Ci-C4)alkyl groups, or piperazines optionally substituted by one or more (Ci-C4)alkyl groups. Preferably, the organic alkaline agents are organic amines, especially tertiary amines, such as tri(Ci-C6)alkylamines.

[0097] Preferably, the alkalizing agents are chosen from the group consisting of alkali or alkaline earth metal hydroxides, in particular sodium hydroxide, alkali or alkaline earth metal (bi)carbonates, in particular sodium or potassium (bi)carbonates and organic amines, preferably tertiary, such as triethylamine or diisopropylethylamine.

[0098] Preferably, the alkalizing agents are minerals.

[0099] More preferably, the alkalizing agents are mineral and are chosen from the group consisting of alkali or alkaline-earth metal hydroxides, alkali or alkaline-earth metal (bi)carbonates, and mixtures thereof, in particular alkali or alkaline-earth metal hydroxides, in particular sodium hydroxide.

[0100] The acidifying agents that can be used in the process according to the invention are all acidification means known to those skilled in the art, such as bipolar electrodialysis or the addition of mineral acidifying agents, in particular of the mineral acid type such as sulfuric acid, phosphoric acid, sulfonic acid, phosphonic acid, H+Hal acids with Hal representing a halogen atom chosen from the group consisting of chlorine, bromine and iodine, preferably H+Hal acids with Hal preferably representing a chlorine atom; preferably by adding mineral acidifying agents, in particular of the mineral acid type such as sulfuric acid, phosphoric acid, sulfonic acid, phosphonic acid, H+Hal acids with Hal representing a halogen atom chosen from the group consisting of chlorine, bromine and iodine, preferably H+Hal acids with Hal preferably representing a chlorine atom.

[0101] More preferably, the acidifying agent is hydrochloric acid. Purification process

[0102] As indicated previously, the invention relates in particular to a purification process (PU) of at least one aqueous medium comprising at least one cosmetic ingredient, and at least one salt; said process (PU) comprising the use of at least one cationic ion exchange resin (PI) and at least one electrodialysis (P2).

[0103] In other words, the invention relates in particular to a purification process (PU) of at least one aqueous medium comprising: - at least one cosmetic ingredient, in particular at least one compound of formula (I), as described above, at least one salt;

[0104] said method (PU) comprising at least one treatment step (PI) of said aqueous medium, carried out with at least one cationic ion exchange resin, and at least one electrodialysis step (P2) of said aqueous medium; said electrodialysis step(s) (P2) preferably being carried out after said treatment step(s) (PI).

[0105] For the purposes of the present invention, the terms “cosmetic ingredients” or “cosmetic agents” are used interchangeably. Purification process - aqueous medium

[0106] Preferably, the aqueous medium comprises at least one compound of formula (I) as described above and at least one salt.

[0107] Preferably, the aqueous medium comprises at least one compound of formula (I) as described above, at least one salt, and at least one alkaline agent as defined above.

[0108] In other words, the purification process according to the invention can also use at least one alkaline agent, preferably as defined above. Compound of formula (I)

[0109] As indicated above, the compound of formula (I) corresponds to the following formula (I): ITS? X^'

[0110] [YES] (I) Formula (I) in which: SA' represents a monosaccharide group or a polysaccharide group comprising up to 20 sugar units, in particular up to 6 sugar units, preferably a monosaccharide, disaccharide or trisaccharide, more preferably a monosaccharide, in pyranose and / or furanose form and of the L and / or D series, said monosaccharide or polysaccharide being substituted by at least one free hydroxyl group, and optionally at least one amine group optionally protected in particular by an acetyl group R'-C(Y)- with R' representing a hydrogen atom, or a (Ci-C6)alkyl group such as methyl, and Y represents O, S, preferably O, the bond between SA and -CH2X is a bond of C-anomeric nature, X represents a divalent group chosen from: -C(O)- or -CH(OR)-, R represents a hydrogen atom, a C1-C10 alkyl group, preferably C1-C4, such as methyl, or an alkyl(Ci-C4)carbonyl group such as acetyl, preferably a hydrogen atom; - Ri represents a hydrocarbon chain, saturated or unsaturated, linear or branched, cyclic or acyclic, preferably acyclic, in C1-C10, preferably in C1-C6, more preferably in C1-C4, more preferably saturated, in particular in C1;

[0112] as well as one of its optical isomers, geometric isomers, and / or one of its solvates such as hydrates.

[0113] By "bond between SA' and CH2-X" which "is a bond of C-anomeric nature" is meant that the part of the sugar unit SA' is connected to the rest of the molecule via the methylene group -CH2- by a carbon-carbon bond CC (i.e. carbon of the sugar SA-carbon of the methylene -CH2-) and not by an oxygen-carbon bond OC (i.e. not by an oxygen bond of the sugar SA' - carbon of the methylene -CH2-).

[0114] SA' may represent a monosaccharide group or a polysaccharide group comprising up to 20 sugar units, in particular up to 6 sugar units, in pyranose and / or furanose form and of L and / or D series, of anomer a or b, and- said monosaccharide or polysaccharide comprising at least one free hydroxy group and optionally at least one optionally protected amine group.

[0115] According to one embodiment, SA' is a monosaccharide group selected from the group consisting of glucose, galactose, mannose, xylose, fucose, arabinose, rhamnose, glucuronic acid, galacturonic acid, iduronic acid, N-acetyl-glucosamine, N-acetyl-galactosamine and more particularly SA is a monosaccharide selected from the group consisting of D-glucose, D-galactose, D-mannose, D-xylose, L-fucose, L-arabinose, L-rhamnose, D-glucuronic acid, D-galacturonic acid, D-iduronic acid, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine.

[0116] Preferably, SA is a monosaccharide selected from the group consisting of glucose, xylose, N-acetyl-galactosamine or fucose, in particular glucose, xylose or fucose, more particularly xylose

[0117] More preferably, SA' is a monosaccharide group chosen from the group consisting of D-glucose, D-xylose, N-acetyl-D-galactosamine or L-fucose, in particular D-glucose, D-xylose or L-fucose, more particularly D-xylose.

[0118] According to one embodiment, SA' is a polysaccharide group comprising up to 6 sucrose units and chosen from the group consisting of D-maltose, D-lactose, D-cellobiose, D-maltotriose, a disaccharide combining a uronic acid chosen from D-iduronic acid or D-glucuronic acid with a hexosamine chosen from D-galactosamine, D-glucosamine, N-acetyl-D-galactosamine, N-acetyl-D-glucosamine, an oligosaccharide containing at least one xylose advantageously chosen from xylobiose, methyl-beta-xylobioside, xylotriose, xylo- tetraose, xylopentaose and xylohexaose and preferentially xylobiose which is composed of two xylose molecules linked by a 1-4 bond.

[0119] Preferably, SA' represents a monosaccharide group.

[0120] Preferably, SA' represents a monosaccharide group chosen from the group consisting of glucose, in particular D-glucose, xylose, in particular D-xylose, fucose, in particular L-fucose, arabinose, in particular L-arabinose, rhamnose, in particular L-rhamnose, glucuronic acid, in particular D-glucuronic acid, galacturonic acid, in particular D-galacturonic acid, iduronic acid, in particular D-iduronic acid, N-acetyl glucosamine, in particular N-acetyl-D-glucosamine, N-acetyl-galactosamine, in particular N-acetyl-D-galactosamine, and preferably SA is chosen from D-glucose, D-xylose, L-fucose, L-arabinose, L-rhamnose, D-glucuronic acid, D-galacturonic acid, D-iduronic acid

[0121] Preferably, SA' represents a monosaccharide group chosen from the group consisting of glucose, xylose, N-acetyl-galactosamine or fucose, more preferably SA is chosen from the group consisting of glucose, xylose or fucose.

[0122] Preferably, SA' represents a monosaccharide group chosen from the group consisting of D-glucose, D-xylose, N-acetyl-D-galactosamine or L-fucose, more preferably SA is chosen from the group consisting of D-glucose, D-xylose or L-fucose.

[0123] More preferably, SA' represents a xylose group and even more preferably D-xylose.

[0124] As indicated previously, Ri represents a hydrocarbon chain, linear or branched, saturated or unsaturated, cyclic or acyclic, in C1-C10, preferably in C1-C6, more preferably in C1-C4, in particular in Cp

[0125] According to one embodiment, Ri represents a linear or branched, saturated or unsaturated, cyclic or acyclic, preferably acyclic, C1-C6, more preferably C1-C4, in particular Cp, hydrocarbon chain.

[0126] According to one embodiment, Ri represents a linear or branched, saturated or unsaturated, preferably saturated, cyclic alkyl chain such as cyclohexyl or cyclopentyl, or acyclic in C1-C6, more preferably in C1-C4, in particular in C1-

[0127] Preferably, Ri represents a linear or branched, preferably linear, saturated or unsaturated, acyclic, preferably saturated, C1-C10, preferably C1-C6, more preferably C1-C4, in particular Cp, hydrocarbon chain.

[0128] Preferably, Ri represents a linear, saturated or unsaturated, acyclic, preferably saturated, C1-C10, preferably C1-C6, more preferably C1-C4, in particular Cp alkyl chain.

[0129]

[0130]

[0131]

[0132]

[0133]

[0134]

[0135] Preferably, Ri represents a linear, saturated or unsaturated, acyclic, C1-C4, in particular Cp, alkyl chain. Preferably, X represents a divalent radical -C(O)- or -CH(OH)-. Advantageously, in formula (I): - X represents a divalent radical -C(O)- or -CH(OH)-, - SA represents a monosaccharide group selected from the group consisting of D-glucose, D-galactose, D-mannose, D-xylose, L-fucose, L-arabinose, L-rhamnose, D-glucuronic acid, D-galacturonic acid, D-iduronic acid, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, preferably selected from D-glucose, D-galactose, D-mannose, D-xylose, L-fucose, L-arabinose, L-rhamnose, D-glucuronic acid, D-galacturonic acid, D-iduronic acid, more preferably selected from D-glucose, D-xylose or L-fucose; - Ri represents a linear, saturated or unsaturated, acyclic, preferably saturated, C1-C10, preferably C1-C6, more preferably C1-C4 hydrocarbon chain, in particular a methyl group. Preferably, the compound of formula (I) is a compound corresponding to the following formula (!): (D Formula (!) in which: - n is equal to 0 or 1, preferably is equal to 1, - p is an integer ranging from 1 to 4, preferably the index p is equal to 3, - Ri has the same meaning as in formula (I), preferably represents a linear alkyl chain, preferably acyclic, in C1-C10, preferably in C1-C6, more preferably in C1-C4, in particular in C1; - X represents a divalent radical -C(O)- or -CH(OR)-, - R represents a hydrogen atom, a C1-C10 alkyl group, preferably C1-C4, such as methyl, or an alkyl(C1-C4)carbonyl group such as acetyl; preferably R represents a hydrogen atom; as well as one of its optical isomers, geometric isomers, and / or one of its solvates such as hydrates. In other words, the compound of formula (I) is preferentially chosen from the group consisting of the compounds of formula (!') as well as one of its optical isomers, geometric isomers, and / or one of its solvates such as hydrates, and their mixtures.

[0136] Preferably, in the formula (!'), the index n is equal to 1 and the index p is an integer varying from 1 to 4, preferably the index p is equal to 3.

[0137] Preferably, the compound of formula (I) is a compound corresponding to the following formula (I”): Here

[0138] (I”)

[0139] Formula (I”) in which: - Ri has the same meaning as in formula (I), preferably represents a linear alkyl chain, preferably acyclic, in C1-C10, preferably in C1-C6, more preferably in C1-C4, in particular in C1; - X represents a divalent radical -C(O)- or -CH(OR)-, preferably -C(O)- - R represents a hydrogen atom, a C1-C10 alkyl group, preferably C1-C4, such as methyl, or an alkyl(CrC4)carbonyl group such as acetyl; preferably R represents a hydrogen atom;

[0140] as well as one of its optical isomers, geometric isomers, and / or one of its solvates such as hydrates.

[0141] In other words, the compound of formula (I) is more preferably chosen from the group consisting of the compounds of formula (I”) and their mixtures.

[0142] Preferably, in formula (I”), R is a hydrogen atom.

[0143] Preferably, the compound of formula (I) is a compound corresponding to the formula (F”) following:

[0144] Formula (F”) in which:

[0145] X corresponds to a divalent radical -C(O)- or -(CH)OH-, preferably -C(O)-

[0146] as well as one of its optical isomers, geometric isomers, and / or one of its solvates such as hydrates.

[0147] The cosmetic ingredient(s), and preferably the compound(s) of formula (I) as described above, may be present in a content of at least 25% by weight of active material of cosmetic ingredient and in particular of formula (I), preferably in a content ranging from 25% to 80% by weight, more preferably ranging from 25 to 75% by weight, more preferably ranging from 30% to 70% relative to the total weight of the aqueous medium.

[0148] Preferably, the aqueous medium comprises at least one compound of formula (!') in a content of at least 25% by weight, preferably in a content ranging from 25 to 80% by weight, more preferably in a content ranging from 28 to 75% by weight, relative to the total weight of the aqueous medium.

[0149] More preferably, the aqueous medium comprises at least one compound of formula (I”) or (I”') in a content of at least 25% by weight, preferably in a content ranging from 40 to 80% by weight, more preferably in a content ranging from 50% to 75% by weight, relative to the total weight of the aqueous medium. Salt

[0150] According to a general characteristic of the present invention, said at least one salt is in particular different from a surfactant.

[0151] Preferably, said at least one salt is chosen from the group consisting of inorganic salts, organic salts and their mixtures.

[0152] Preferably, said at least one salt is chosen from the compounds of formula (IV):

[0153] / )^(^)

[0154] Formula (IV) in which:

[0155] y is an integer ranging from 1 to 3,

[0156] w is an integer ranging from 1 to 3,

[0157] A is an organic or inorganic anion, preferably organic,

[0158] D is an organic or inorganic cation, preferably inorganic,

[0159] The salt respects electroneutrality, that is to say that the absolute value of the sum of the negative charges of the anions is equal to the sum of the positive charges of the cations.

[0160] Preferably, in formula (IV),

[0161] w is equal to 1 or 2, preferably 1,

[0162] y is equal to 1 or 2, preferably 1.

[0163] Preferably, in formula (IV), w is equal to 1 and y is equal to 1.

[0164] Aw may be an inorganic anion selected from the group consisting of nitrate (NO3 ), carbonate (CO32 ), halides, in particular chloride (Cl ), more preferably in the group consisting of nitrate (NO3 ) and halides, in particular chloride (Cl ).

[0165] Aw may be an organic anion chosen from the group consisting of CrCi8, preferably Ci-Cio, preferentially Ci-C6, more preferentially Ci-C4, even more preferentially Ci-C2, better still C2, in particular from a group consisting of Ci-C6 carboxylic acids.

[0166] Preferably, Aw is an organic anion, preferably chosen from the group consisting of CrCi8 carboxylic acids, linear or branched, cyclic or not, preferably C1-C10, more preferably C1-C6.

[0167] Preferably, Aw is an organic union chosen from the group consisting of linear CrCi8 carboxylic acids, more preferably Ci-C6.

[0168] Preferably, Aw is an organic anion chosen from the group consisting of C1-C4 carboxylic acids, preferably C1-C2, better still C2 such as acetate (CH3COO).

[0169] According to one embodiment, D'+ may be an organic cation, preferably chosen from the group consisting of ammonium, phosphonium, imadazolium, pyrazolium, piperidinium, piperazinium ions.

[0170] According to one embodiment, D'+ is an inorganic cation chosen from the group consisting of alkali metal cations and alkaline earth metal cations.

[0171] Advantageously, D'+ is a cation chosen from the group consisting of alkali metal cations, alkaline earth metal cations, the ammonium ion (NH4+), in particular alkali metal cations, alkaline earth metal cations.

[0172] Preferably, D'+ is a cation selected from the group consisting of calcium ion (Ca 2+), magnesium ion (Mg2+), sodium ion (Na+) and potassium ion (K+), in particular calcium ion and sodium ion, more particularly sodium ion.

[0173] Preferably, the salt corresponds to the following formula (IV1):

[0174] (IV1)

[0175] Formula (IV1) in which:

[0176] D+ has the same meaning as that given in formula (IV) with y=l,

[0177] R2 represents an alkyl chain, saturated or unsaturated, linear or branched, cyclic or acyclic, preferably acyclic, in C1-C10, preferably in C1-C6, more preferably in C1-C4, in particular in Cp

[0178] Preferably, R2 represents a linear or branched, saturated or unsaturated, cyclic or acyclic, preferably acyclic, C1-C6, more preferably C1-C4, in particular Cp alkyl chain.

[0179] According to one embodiment, R2 represents a linear or branched, saturated or unsaturated, cyclic alkyl chain such as cyclohexyl or cyclopentyl, or acyclic in C1-C6, more preferably in C1-C4, in particular in Cp

[0180] Preferably, R2 represents a linear or branched, preferably linear, saturated or unsaturated, acyclic, C1-C10, preferably C1-C6, more preferably C1-C4, in particular Cp alkyl chain.

[0181] Preferably, R2 represents a linear, saturated or unsaturated, acyclic, C1-C10, preferably C1-C6, more preferably C1-C4, in particular Cp, alkyl chain.

[0182] Preferably, R2 represents a linear, saturated or unsaturated, acyclic, C1-C4, in particular Cp, alkyl chain.

[0183] Preferably, in formula (IV1), D+ represents an inorganic cation chosen from the group consisting of alkali metal cations and alkaline earth metal cations.

[0184] Advantageously, in formula (IV1), D+ is a cation chosen from the group consisting of alkali metal cations, alkaline earth metal cations, the ammonium ion (NH4+), in particular alkali metal cations, alkaline earth metal cations, in particular the sodium ion (Na+), the potassium ion (K+) or an ammonium (NH4+).

[0185] More preferably, in formula (IV1), D+ represents the sodium ion (Na+).

[0186] Preferably, said at least one salt is chosen from the group consisting of salts of alkali metals, alkaline earth metal salts, ammonium salts and their mixtures.

[0187] Preferably, said at least one salt is chosen from the group consisting of calcium salts, magnesium salts, sodium salts, potassium salts and mixtures thereof, more preferably chosen from the group consisting of calcium salts, sodium salts and mixtures thereof.

[0188] Preferably, said at least one salt is chosen from the group consisting of alkali metal salts of C1-C6, preferably C1-C4, more preferably C1-C2, better still C2, carboxylic acids, such as sodium acetate.

[0189] Preferably, said at least one salt is chosen from the group consisting of alkali metal salts, alkaline earth metal salts, ammonium salts and mixtures thereof.

[0190] Preferably, said at least one salt is chosen from the group consisting of calcium salts, magnesium salts, sodium salts, potassium salts and mixtures thereof, more preferably chosen from the group consisting of calcium salts, sodium salts and mixtures thereof.

[0191] Preferably, said at least one salt is chosen from the group consisting of alkali metal salts of C1-C6, preferably C1-C4, more preferably C1-C2, better still C2, carboxylic acids, such as sodium acetate.

[0192] Salt may or may not be an impurity.

[0193] Preferably, the salt may be an impurity, for example resulting from at least one of the steps of a process for preparing at least one cosmetic ingredient, preferably at least one compound of formula (I) and / or resulting from at least one step of at least one washing and / or purification process(es) carried out before, after or during, preferably after, at least one of the steps of a process for preparing said at least one cosmetic ingredient, preferably said at least one compound of formula (I).

[0194] Preferably, the salt is an impurity.

[0195] The salt, preferably of formula (IV1), more preferably of formula (IV1), may be present in a content ranging from 0.05% to 50% by weight, in particular in a content ranging from 0.1% to 40% by weight, more particularly in a content ranging from 0.5% to 30% by weight, relative to the total weight of the aqueous medium.

[0196] More preferably, the salt corresponding to formula (IV1) may be present in a content ranging from 0.05% to 45% by weight, in particular in a content ranging from 0.1% to 35% by weight, more particularly in a content ranging from 0.5% to 25% by weight, relative to the total weight of the aqueous medium by weight, relative to the total weight of the aqueous medium. Step (PI) and Step (P2)

[0197] As indicated previously, the method (PU) comprises the implementation of at least one cationic ion exchange resin (PI) and at least one electrodialysis (P2).

[0198] According to one embodiment, step (P2) can be implemented before step (PI).

[0199] Preferably, the step of implementing with at least one ion exchange resin (PI) is performed before electrodialysis (P2).

[0200] In other words, the purification process (PU) comprises at least one step (PI) of treating said aqueous medium with at least one cationic ion exchange resin, and at least one step (P2) of electrodialysis of said aqueous medium.

[0201] Preferably, the step(s) (PI) is or are implemented before the step(s) (P2).

[0202] More preferably, the purification process (PU) comprises a step (PI) and a step (P2); step (PI) being implemented before step (P2). Processing Step (PS)

[0203] For the purposes of the present invention, the terms “step (PI)” and “processing step (PI)” are used interchangeably.

[0204] As indicated previously, the method according to the invention comprises at least one step (PI) carried out with at least one cationic ion exchange resin of at least one aqueous medium comprising at least said cosmetic ingredient, preferably at least said compound of formula (I) as described previously, and at least one salt as defined previously, preferably at least said compound of formula (IV).

[0205] The treatment step(s) (PI) of the reaction medium is or are carried out with at least one cationic ion exchange resin, preferably at least one weak cationic resin, for example a resin having active carboxylic groups, and / or at least one strong cationic resin, preferably at least one sulfonic resin.

[0206] Preferably, the treatment step(s) (PI) is or are carried out with at least one cationic resin having carboxylic groups and / or at least one sulfonic resin, preferably at least one sulfonic resin.

[0207] Preferably, the treatment step(s) (PI) is or are carried out with at least one cationic resin comprising one or more carboxylic groups and / or one or more sulfonic groups.

[0208] Preferably, the treatment step(s) (PI) of the reaction medium comprising at least one cosmetic ingredient, preferably at least one compound of formula (I), and at least one salt, preferably at least one compound of formula (IV) and more preferably at least one compound of formula (IV1), is or are carried out with at least one sulfonic resin.

[0209] Preferably, the cationic ion exchange resin is a sulfonic resin comprising one or more sulfonic groups (SO3H) and / or one or more sulfonate groups (-SO3), more preferably one or more sulfonate groups (-SO3).

[0210] Preferably, the treatment step(s) (PI) are carried out at a pH value greater than or equal to the pKa of the compound corresponding to the following formula (IV'): G •s-

[0211] Formula (IV') in which R2 has the same meaning as in formula (IV).

[0212] Preferably, the processing step(s) (PI) are implemented at a value of pH greater than or equal to the lowest pKa of the compound of formula (IV') if several are present in the aqueous reaction medium.

[0213] Preferably, the treatment step(s) (PI) is or are carried out in a pH range from 3 to 8, more preferably from 4 to 8.

[0214] The treatment step (PI) can be carried out one or more times, preferably once.

[0215] Preferably, the treatment step (PI) is carried out in an aqueous medium as described previously, more preferably in an aqueous medium free of any organic solvent.

[0216] Advantageously, the treatment step (PI) is not carried out in addition to at least one washing step with at least one organic solvent, preferably at least one water-miscible organic solvent. Step (P2)

[0217] For the purposes of the present invention, the terms “step (P2)” and “electrodialysis step (P2)” are used interchangeably.

[0218] As indicated previously, the method according to the invention comprises at least one electrodialysis step (P2) of at least one aqueous medium comprising at least said cosmetic ingredient, preferably at least said compound of formula (I) as described previously, and at least one salt as defined previously, preferably at least said compound of formula (IV) and more preferably at least said compound of formula (IV1).

[0219] In other words, the method according to the invention preferably comprises at least one step (P2) during which at least the aqueous medium including at least said compound of formula (I) and at least said compound of formula (IV) is subjected to at least one electrodialysis, preferably one electrodialysis.

[0220] Even more preferably, the method according to the invention preferably comprises at least one step (P2) during which at least the aqueous medium including at least said compound of formula (I) and at least said compound of formula (IV1) is subjected to at least one electrodialysis, preferably to one electrodialysis.

[0221] In other words, the aqueous medium, as defined above, is conveyed into an electrodialyzer to separate said salt(s) from said aqueous medium.

[0222] The method of the invention implements an electrolysis step. Electrodialysis is a method known to those skilled in the art; it is an electrochemical process which makes it possible to extract ions (anions or cations) contained in a solution (see, for example, chemical news, Electrodialysis and its numerous applications, F. Lutin - no. 327-328, February-March 2009).

[0223] The principle of the process is to use electrically charged membranes (cationic or anionic) used to separate the medium ions from the solution, in particular aqueous, using the driving force of the potential difference. The electrodialysis device is often built on the principle of a filter press of stacking successive membranes which can include several tens or even hundreds of cationic and anionic membranes alternating between two electrodes, the solution, in particular aqueous, arriving in the device (feed solution) flows through the different cells (i.e. space between 2 successive membranes also pair of membranes). When an electrical potential difference is applied between 2 electrodes the positively charged cations in the solution feed ions move towards the cathode. These ions easily pass through the negatively charged cation exchange membranes, but are retained by the positively charged anion exchange membranes. And conversely, negatively charged anions migrate towards the anode, pass through the anion exchange membrane and are retained by the cation exchange membrane. Thus the arrangement of ion-selective membranes, the migrating ions concentrate in each alternating cell of the stack. Thus, the ions removed from the aqueous feed solution are concentrated into two separate streams.

[0224] In summary, the extraction of ions is done by migration of ions through at least two selective membranes (anionic or cationic) under the action of an electric field. Only anions can cross an anionic membrane and only cations can cross a cationic membrane. By placing several membranes in parallel, allowing positive ions and negative ions to pass alternately, certain ions can be eliminated from the solution, particularly aqueous.

[0225] Thus, electrodialysis can separate, concentrate and / or purify a C-glycoside derivative such as a compound of formula (I), from aqueous solutions.

[0226] In some compartments there is concentration of ions and in others the ions are eliminated. Particles not carrying an electrical charge are not eliminated.

[0227] In the method of the invention, conventional electrodialysis (ED) or bipolar electrodialysis (BPED) can be used.

[0228] According to one embodiment of the invention, the method implements conventional electrodialysis.

[0229] By "conventional electrodialysis" or ED or concentration electrodialysis is meant a device implementing the electrochemical separation of ions from a composition, in particular aqueous, transferred from one membrane to another by selective exchange using a continuous electrical voltage. Conventional electrodialysis therefore makes it possible to purify, concentrate and demineralize.

[0230] By "bipolar electrodialysis" or BPED is meant an ion exchange device by electrodialysis membranes that uses at least one bipolar membrane to split water into proton and hydroxide ion, i.e. generating acid and alkali flows. Under the driving force of an electric field, a bipolar membrane dissociates water into hydrogen ions (H+) and hydroxide (OH ). A bipolar membrane is formed of an anion and cation exchange layer that are bonded together, and a very thin interface where water diffuses from external aqueous saline solutions. With the anion exchange side facing the anode and the cation exchange side facing the cathode, hydroxyl anions will be transported through the anion exchange layer and hydrogen cations through the cation exchange layer. A bipolar membrane allows the generation and concentration of hydroxyl ions and hydrogen on its surface. These ions can be used in an electrodialysis stack to combine with the cations and anions of the salt to produce acids and bases (or alkaline agent).

[0231] This process allows the pH of a solution to be adjusted without having to add an alkaline or acid agent.

[0232] The membranes of the electrolysis device are anionic or cationic. The cationic membranes are often made of sulfonated or phosphonated polymers such as sulfonated polystyrenes, while the anionic membranes are often made of quaternary ammonium, phosphonium polymers such as polystyrenes with quaternary ammoniums. Preferably the membranes are sulfonated and quaternary ammonium.

[0233] It may be necessary to carry out pre-treatment before electrodialysis. Suspended solids with a diameter greater than 10 mm must be removed, otherwise they may clog the pores of the membrane. There are also substances that are capable of neutralizing the membrane, such as large organic anions, colloids, iron and manganese oxides. They disrupt the selective effect of the membrane.

[0234] Before electrolysis the composition can be filtered or passed through an ion exchange resin.

[0235] Before electrodialysis, the pH of the aqueous composition comprising the cosmetic ingredient(s) has a pH higher than the pKa of the salt of the conjugate acid (weak acid). Preferably before electrolysis the pH of the aqueous composition comprising the C-glycoside derivatives is preferably at least 4, more preferably at least 5, even more preferably at least 6, even more preferably at least 7. The pH can be adjusted using an alkaline or acidic agent such as acetic acid, sodium hydroxide or (bi)carbonates of alkaline agents.

[0236] Anion exchange membranes or cation exchange membranes suitable for concentration by electrodialysis may be used in the methods of the present invention. Such membranes are commercially available from Astom Corp. (Tokyo, Japan), for example Neosepta membranes, Tokuyama Co., Ltd. (Tokyo, Japan), Ameridia (Somerset).

[0237] The conventional electrodialysis step can be performed with any commercially available electrodialysis unit. Such units are commercially available from various suppliers such as Valeo (France), Eurodia Industrie SA (France). Eet Corporation (US), Ameridia (US), or Mega AS (Czech Republic).

[0238] Concentrating electrodialysis is preferably carried out using a configuration known as an electrodialysis cell. The cell consists of a feed (diluate) compartment and a concentrate (brine) compartment. formed by an anion exchange membrane and a cation exchange membrane placed between two electrodes. The electrodialysis process preferably uses multiple electrodialysis cells arranged in a configuration known as an electrodialysis stack, with alternating anion and cation exchange membranes forming the multiple electrodialysis cells. The number of cells can range from a few cells, for example ten cells, to hundreds of cells in a stack.

[0239] Electrodialysis parameters include current density, cell voltage, current efficiency, diluate concentration, and concentrate concentration.

[0240] The amount (density) of current determines the amount in equivalent grams of product are transported across the membranes. Operation at high current density can reduce the required surface area of ​​the electrodialysis cells. The current density is preferably balanced with the increase in cell voltage, which nevertheless can result in higher energy consumption.

[0241] By "limiting current" is meant the maximum current density allowed to avoid an abrupt increase in the cell voltage. The limiting current may depend on parameters such as the design of the battery, the concentrations of the composition, in particular aqueous, the temperature, etc.

[0242] The current efficiency also determines the surface area of ​​the membranes required for the process of the present invention.

[0243] By "current efficiency" is meant the efficiency of an electrochemical process.

[0244] Current efficiency takes into account all potential parasitic phenomena occurring in the membrane stack (e.g. membrane permselectivity < 100%, physical leakage (leading to impurities in the products, which can be reduced by optimized stack design and membrane selection).

[0245] According to a particular embodiment of the invention, the ratio of electrical energy consumed / kg is between 0.01 kW / h and 0.2 kW / h / kg, better between 0.03 kW / h / kg and 0.1 kW / h / kg.

[0246] Another important parameter is the concentrations (conductivities) of the two streams. The ratio of the conductivities affects the efficiency of the current, limiting the maximum concentration for the concentrate (brine) stream. In general, the minimum diluate concentration is limited by conductivity considerations due to the ohmic resistance of the diluate cells and the low limiting currents at low conductivities. The minimum conductivity that can be considered is about 0.5 mS / cm. The minimum starting concentration of salts / cosmetic ingredient, especially C-glycoside derivative, for carrying out concentration electrodialysis is that whose conductivity is preferably at least 10 mS / cm, more preferably at least 20 mS / cm, even more preferably at least 30 mS / cm.

[0247] According to a particular embodiment of the invention, the composition, in particular aqueous, is preferably pretreated to remove impurities and particles, in particular to remove acetic acid. Any pretreatment method known to those skilled in the art may be used, such as centrifugation, microfiltration, nanofiltration, ion exchange or distillation, in particular by distillation, preferably under reduced pressure.

[0248] When the membranes are fouled by impurities, they can be cleaned using conventional methods known to those skilled in the art such as the use of current reversal solutions or dilute, caustic and / or enzymatic acid.

[0249] The temperature range in conventional or bipolar electrodialysis stacks is preferably between 10°C and 50°C, in particular at a temperature between 35°C and 40°C.

[0250] The pH range in electrodialysis stacks, particularly conventional ones, is preferably between 3 and 8, more preferably between 4 and 7.

[0251] According to a particular embodiment, the conventional or bipolar electrodialysis of the method of the invention is carried out at a temperature between 10°C and 50°C, particularly between 15°C and 40°C, preferably the temperature is between 20°C and 35°C such as 25°C.

[0252] According to one embodiment, the method of the invention implements a conventional electrolysis step, in particular carried out at a pH of at least 4, preferably at least 5, more preferably at least 6 and preferably at a pH less than or equal to 8.

[0253] According to a particular embodiment of the invention in the electrodialysis step of the process, the composition, in particular aqueous, comprising at least said compound of formula (I) and at least said compound of formula (IV) is introduced into the electrodialysis cell through the diluate compartment.

[0254] When the solution reaches the active zone of the cells, the direct current (DC) voltage causes the positively charged cations to migrate to the cathode and the negatively charged anions to migrate to the anode. When the ions reach an ion exchange membrane, the properties of the membrane determine whether the ions are rejected or allowed to pass through. Ions that can pass through membranes are retained in the next compartment since the next membrane in its path will be of the opposite charge. Therefore, there are compartments from which ions are removed and compartments where they are concentrated. If the solutions are circulated rapidly through the cell, a diluate stream and a concentrate stream are obtained. The product can be the desalinated stream, the concentrated stream or both. Bipolar membrane electrodialysis

[0255] According to a preferred embodiment of the invention, the method implements at least one bipolar or bipolar membrane electrodialysis step.

[0256] This bipolar electrodialysis may involve first bringing into contact the concentrate resulting from conventional electrodialysis followed by at least one bipolar membrane electrodialysis to convert the C-glycoside derivatives of formula (I).

[0257] According to a preferred embodiment of the invention, the method implements a bipolar electrodialysis step without first carrying out a conventional electrodialysis step.

[0258] Bipolar membrane electrodialysis can be performed with any available bipolar membrane electrodialysis unit. Such units are commercially available from suppliers such as The Electrosynthesis Company, Inc. (US), FuMA-Tech GmbH (Germany), Solvay SA (Belgium), Tokuyama Co., Ltd. (Japan), Graver Water Co. (US), Tianwei, Membrane Technology Co. Ltd. (China), Ameridia (US), Eurodia Industrie SA (France).

[0259] Any bipolar membrane suitable for bipolar membrane electrodialysis may be used in the methods of the present invention. Such membranes are commercially available from Astom Corp. (Tokyo, Japan), for example Neosepta membranes, Tokuyama Co., Ltd. (Tokyo, Japan), Ameridia (Somerset, NJ, USA), Eurodia Industrie SA (Wissous, France), CelTech, Inc. (Fayetteville, NC, USA), Eden Purification Systems (North Haven, CT, USA), Ion Power, Inc. (Bear, DE, USA), Minntech Corporation (Minneapolis, MN, USA) and GE Water & Process Technologies (Trevose, PA, USA), Veolia (France).

[0260] Examples include the membranes marketed by Veolia AR204; AR103, AR908, CR64, CR67, CR61. The membranes can be woven or the polymers can be cast onto a variety of fabrics. Each type of fabric is designated by a single letter:

[0261] R —> Woven acrylic fabric, H —> Heavy woven acrylic fabric, E —> Non-woven polyester fabric woven, T —> fine non-woven polyester fabric, U —> ultra-fine non-woven polyester fabric, P —> polypropylene woven fabric, N —> fine non-woven polypropylene fabric. The name of each membrane type can be the combination of membrane chemistry and support structure (e.g. AR103P, CR67T). Membranes have certain electrical resistance, and permselectivity

[0262] Ion exchange membranes such as lonics have certifications e.g. NSF 61 for drinking water, 21CFR175 176 177 178 182; EU 1935 / 2004 and EU 10 / 2001 for food contact materials

[0263] According to a particular embodiment, the bipolar membrane electrodialysis of the method of the invention is carried out at a temperature between 10°C and 40°C, particularly between 15°C and 35°C, preferably the temperature is between 20°C and 30°C such as 25°C.

[0264] It is understood herein that the concentrating electrodialysis unit and the bipolar membrane electrodialysis unit may be integrated into the same apparatus.

[0265] Different configurations of bipolar membrane electrodialysis are possible and described by the manufacturers.

[0266] A three-compartment cell is obtained by adding the bipolar membrane into a conventional electrodialysis cell. In such a case, the bipolar membrane is flanked on either side by the anion and cation exchange membranes described above to form three compartments: acid between the bipolar and anion exchange membranes, base between the bipolar and cation exchange membranes, and salt between the cation and anion exchange membranes.

[0267] A two-compartment cell can be obtained by adding bipolar and cation exchange membranes or by adding bipolar and anion exchange membranes.

[0268] According to one embodiment of the invention, an alternation of cation exchange membranes and bipolar membranes is used.

[0269] Advantageously, the electrodialysis step is carried out at a pH ranging from 4 to 9, preferably at a pH ranging from 4.5 to 8.5, more preferably in a pH range from 5 to 8, more preferably at a pH ranging from 6.5 to 7.5.

[0270] The electrodialysis step (PU1) is preferably carried out at a pH of less than 8 so as to effectively reduce the contents of ionic impurities, i.e. the salt contents, preferably corresponding to formula (II), more preferably to formula (II').

[0271] The electrodialysis step can be carried out at a temperature ranging from 20 to 50°C, preferably at a temperature ranging from 25°C to 45°C.

[0272] Preferably, the electrodialysis step is carried out with conventional electrolysis, more preferably at a “product” conductivity (i.e. before treatment) ranging from 50 to 0.05 mS / cm, preferably ranging from 40 to 0.2 mS / cm, measured in particular at a temperature ranging from 20°C to 50°C.

[0273] According to one embodiment, the electrodialysis step is carried out with bipolar membrane electrolysis at a “product” conductivity (i.e. before treatment) ranging from 60 to 0.5 mS / cm, preferably ranging from 55 to 1 mS / cm, more preferably ranging from 50 to 10 mS / cm, even more preferably ranging from 45 to 20 mS / cm, measured in particular at a temperature ranging from 20°C to 50°C. Preferably the concentration of the cosmetic ingredient(s) in particular derives from C-glycoside is between 10 and 70% by weight, particularly between 20 and 60% by weight, more particularly between 30 and 50% by weight.

[0274] Preferably, the electrodialysis step, in particular conventional electrodialysis, is carried out at a pH ranging from 5 to 8, more preferably at a pH ranging from 4 to 8, and at a temperature ranging from 20°C to 50°C, more preferably at a temperature ranging from 25°C to 45°C.

[0275] Preferably, the bipolar membrane electrodialysis electrodialysis step is carried out at an alkaline pH, i.e. > 7, more preferably at a pH greater than or equal to 8, better still greater than or equal to 9, in particular between 9.5 and 12, and at a temperature in particular ranging from 20°C to 50°C, more preferably at a temperature ranging from 25°C to 45°C.

[0276] The electrodialyzer comprises in particular a first electrode, constituting the anode, and a second electrode, constituting the cathode, so that, when a direct current source is applied, an electric field is applied across all of the components of the electrodialyzer between the first electrode and the second electrode.

[0277] Between the first electrode and the second electrode, the electrodialyzer may comprise a series of compartments mounted in parallel and each formed of two membranes, in particular an anionic or anion exchange membrane, i.e. a membrane permeable to anions and impermeable to cations, and a cationic or cation exchange membrane, i.e. a membrane permeable to cations and impermeable to anions. The anionic and cationic membranes are arranged alternately within the electrodialyzer.

[0278] Thus each compartment is formed of an anionic membrane and a cationic membrane which are spaced from each other.

[0279] In other words, the electrodialyzer can be of the conventional type comprising a stack of membranes alternately exchanging cations and exchanging anions, placed in an electric field created by electrodes.

[0280] Between the first electrode and the second electrode, the electrodialyzer comprises a compartment, generally located in the center of the device, called the dilution compartment, in which the aqueous solution, as defined previously, circulates.

[0281] The dilution compartment is arranged between two adjacent compartments, called concentration compartments. In other words, the concentration compartments are located on either side of the dilution compartment. In other words, the dilution and concentration compartments are arranged alternately within the electrodialyzer. In yet other words, the dilution behavior is sandwiched between two concentration compartments.

[0282] Thus, during the circulation of an aqueous medium, as defined previously, in the dilution compartment, on the one hand, under the effect of the electric current, the anions of the salt, attracted towards the anode, will migrate from the dilution compartment towards the concentration compartment by crossing the anionic membrane and will remain blocked in this concentration compartment because of the cationic membrane.

[0283] On the other hand, the cations of the salt, attracted by the cathode, will migrate from the dilution compartment to the concentration compartment by crossing the cationic membrane and will remain blocked in this concentration compartment because of the anionic membrane.

[0284] Thus the salt is extracted from the dilution compartment, in which the aqueous medium circulates, while the anions and cations of the salt are concentrated respectively in each adjacent concentration compartment.

[0285] The electrodialysis step thus makes it possible to reduce the salt content in the aqueous medium as defined previously.

[0286] The aqueous medium according to the invention comprising at least the compound of formula (I), located in the dilution compartment, is then recovered at the outlet of the electrodialysis via a conduit.

[0287] Electrodialysis (P2) advantageously makes it possible to eliminate very large quantities of impurities in ionic form from the aqueous medium comprising at least said compound of formula (I) as defined above.

[0288] The electrodialysis step (P2) thus makes it possible to achieve a content of salt(s), preferably of compound (IV), in particular of formula (IV1), capable of being less than or equal to 10% by weight, preferably is less than or equal to 5% by weight, more preferably varies from 1 to 5% by weight, better still varies from 1.5 to 2% by weight, relative to the total weight of the dry extract containing said compound of formula (I).

[0289] In other words, at the end of the purification process, said compound of formula (I) is preferably in the form of a dry extract comprising a content of less than or equal to 10% by weight, preferably less than or equal to 5% by weight, more preferably varying from 1 to 5% by weight, better still varying from 1.5 to 2% by weight, of at least one salt as defined above, preferably of at least one compound of formula (IV), (IV1) or (IV'), relative to the total weight of the dry extract. Preparation process

[0290] As indicated above, the present invention also relates to a preparation process (PR) of one or more cosmetic ingredients, preferably chosen from the compounds of formula (I), in an aqueous medium, comprising at least one purification (PU) comprising at least one treatment step (PI) of said aqueous medium, carried out with at least one cationic ion exchange resin, and at least one electrodialysis step (P2) of said aqueous medium; said electrodialysis step(s) (P2) preferably being carried out after said step(s) of treatment (PI).

[0291] The step(s) (PI) and the step(s) (P2) are as defined previously.

[0292] In other words, the invention relates in particular to a preparation process (PR) of one or more cosmetic ingredients preferably chosen from compounds of formula (I), comprising: - at least one synthesis step (PRi) of at least one cosmetic ingredient preferably chosen from at least one compound of formula (I), leading to the formation of at least said cosmetic ingredient preferably said compound of formula (I), and at least one salt, as defined above, preferably at least one compound of formula (IV) in particular at least one salt of formula (IV1), in an aqueous medium, optionally, at least one washing and / or neutralization step (PRO), preferably at least one neutralization step (PRO) of the aqueous reaction medium resulting from at least one of the steps of synthesis (PRi), at least one purification (PU) comprising at least one treatment step (PI) of said aqueous medium, carried out with at least one cationic ion exchange resin, and at least one electrodialysis step (P2) of said aqueous medium; said electrodialysis step(s) (P2) preferably being carried out after said treatment step(s) (PI).

[0293] Process for the preparation of at least one compound of formula (I)

[0294] As indicated previously, the method according to the invention comprises: at least one reaction step (i) taking place in an aqueous medium and according to the reaction scheme (A), as described previously, in the presence of: • at least one compound of formula (III), preferably in an equimolar or excess amount relative to the compound of formula (II), preferably in excess, and • at least one alkaline agent, preferably at least one mineral alkaline agent, in an equimolar or excess quantity relative to the compound of formula (II),

[0295] to lead to the formation of at least one compound of formula (IA) (i.e. a compound corresponding to formula (I) in which X corresponds to a divalent radical -CO), and at least one compound of formula (IV), in an aqueous medium; - optionally at least one reaction step (ii) leading to the formation of at least one compound of formula (IB) (i.e. a compound corresponding to formula (I) in which X corresponds to a divalent radical -CH(OR) with preferably R representing a hydrogen atom); - at least one purification (P) of the reaction medium comprising at least the compound of formula (IV1), produced in an aqueous medium, comprising: at least one treatment step (PI), carried out with at least one cationic ion exchange resin, in the aqueous reaction medium resulting from the reaction step(s) (i), at least one electrodialysis step (P2) of said aqueous reaction medium comprising at least said compound of formula (IA) and at least the compound of formula (IV); said electrodialysis step(s) (P2) being carried out after said treatment step(s) (PI); said electrodialysis step(s) (P2) being carried out after said treatment step(s) (PI). Reaction step (i)

[0296] Advantageously, reaction step (i) is carried out in an aqueous medium, in the presence of: of at least one compound of formula (II), of at least one compound of formula (III),, preferably, the molar ratio compound(s) of formula (III) / compound(s) of formula (II) is greater than or equal to 1, preferably between 1 and 5, more preferably between 1 and 4, even more particularly between 1 and 3, better still between 1 and 2, in particular ranging from 1 to 1.5; according to a particular embodiment, the molar ratio compound(s) of formula (III) / compound(s) of formula (II) is greater than 1; of at least one alkaline agent, preferably at least one alkaline agent as described above, preferably mineral, more preferably chosen from the group consisting of alkali or alkaline-earth metal hydroxides, alkali or alkaline-earth metal (bi)carbonates, and mixtures thereof; in particular alkali or alkaline-earth metal hydroxides, such as sodium hydroxide, the alkaline agent being in an equimolar or excess quantity, preferably, the molar ratio of alkaline agent(s) / compound(s) of formula (II) is greater than or equal to 1, preferably between 1 and 5, more preferably between 1 and 4, even more particularly between 1 and 3, better still between 1 and 2; according to a particular embodiment, the molar ratio of alkaline agent / compound of formula (II) is greater than 1 preferably, reaction step (i) takes place: at a temperature ranging from 20°C to 80°C, preferably at a temperature ranging from 20°C to 70°C, more preferably at a temperature temperature ranging from 30°C to 70°C, better from 30°C to 60°C, even better at a temperature ranging from 35°C to 45°C, • preferably, the duration of the reaction varies: • from 10 minutes to 10 hours, preferably from 20 minutes to 5 hours, more preferably from 30 minutes to 4 hours, even more preferably from 45 minutes to 3 hours; • preferably reaction (i) is carried out at atmospheric pressure.

[0297] Preferably, reaction step (i) is carried out in an aqueous medium and successively comprises: • preferably the addition of at least one compound of formula (II) in an aqueous medium, in particular at a temperature ranging from 20°C to 80°C, • preferably, the addition of at least one compound of formula (III) in the aqueous medium comprising at least one compound of formula (II), • - optionally, the temperature is advantageously reduced by at least 5°C, in particular at least 10°C, preferably at least 20°C, before adding at least one alkaline agent • preferably, the addition of at least one alkaline agent, preferably mineral, in an equimolar quantity relative to the compound of formula (II) or in excess, preferably in excess, as described above, while maintaining the temperature preferably less than or equal to 60°C, better still less than or equal to 50°C, even better still less than or equal to 45°C, • preferably, the reaction medium comprising at least one compound of formula (II), at least one compound of formula (III) and at least one alkaline agent, is maintained at the temperature at the end of addition of at least one alkaline agent and / or heated to the reaction temperature as described above, • optionally, at the end of reaction (i), the reaction medium may be cooled by at least 5°C, preferably by at least 10°C, more preferably by at least 15°C.

[0298] Preferably, at the end of the reaction step(s) (i), the pH can be adjusted to a value less than or equal to 8.5, and greater than or equal to 2.5, preferably is adjusted in a range from 2.5 to 8.5.

[0299] The pH can be adjusted by any acidification means known to those skilled in the art such as the use of at least one acid resin and / or by adding at least one acidifying agent as described above, preferably mineral, more preferably chosen from the group consisting of mineral acids as described above.

[0300] According to a particular embodiment, the pH is adjusted by at least one acid resin and optionally by adding at least one acidifying agent as described above. preferably mineral, more preferably chosen from the group consisting of mineral acids as described above.

[0301] According to a preferred embodiment, the method according to the invention comprises a step i). Purification step (P)

[0302] In accordance with the present invention, the purification step (P) is carried out on an aqueous reaction medium comprising at least one impurity of formula (IV) or (IV1).

[0303] The purification step (P) can thus be carried out one or more times on an aqueous reaction medium comprising at least one impurity of formula (IV) or (IV1).

[0304] According to one embodiment, the treatment step (PI) is carried out one or more times and the electrodialysis step (P2) is carried out at least once at the end of at least one step (PI).

[0305] The purification (P) can thus be carried out on an aqueous reaction medium resulting from the reaction step (i) and / or on an aqueous reaction medium resulting from at least one reaction step (ii).

[0306] In other words, the purification(s) (P) can be carried out at least once between a reaction step (i) and at least one reaction step (ii), and / or at least once after at least one reaction step (ii), for example after one and / or two reaction steps (ii).

[0307] According to one embodiment, the purification step (P) is carried out at least once at the end of the reaction step(s) (i).

[0308] According to another embodiment, the purification step (P) is carried out at least once at the end of the reaction step(s) (ii).

[0309] According to a particular embodiment, the purification step (P) is carried out at least once at the end of step(s) (i) and the method of the invention does not include step ii).

[0310] According to another embodiment, the method of the invention comprises at least one step i), preferably one step i), and at least one step ii), preferably one step ii), and the purification step (P) is carried out at least once at the end of at least one step (i) without being carried out at the end of the step(s) (ii).

[0311] According to yet another embodiment, the method of the invention comprises at least one step i), preferably one step i), and at least one step ii), preferably one step ii), and the purification step (P) is carried out at least once at the end of at least one step (ii) without being carried out at the end of the step(s) (i).

[0312] According to another embodiment, the method of the invention comprises at least one step i), preferably one step i), and at least one step ii), preferably one step ii), and the purification step (P) is carried out at least once at the end of at least one step (i) and at least once at the end of at least one step (ii).

[0313] According to a preferred embodiment, the method of the invention comprises a step i), and a step ii), and the purification step (P) is carried out at least once at the end of step (i) without being carried out at the end of step(s) (ii).

[0314] According to one embodiment, the purification step (PI) is carried out at least once at the end of the reaction step(s) (i).

[0315] According to another embodiment, the purification step (P2) is carried out at least once at the end of the reaction step(s) (ii).

[0316] According to another embodiment, the method of the invention comprises at least one step i), preferably one step i), and at least one step ii), preferably one step ii), and a purification step (PI) is carried out at least once at the end of at least one step (i) and a purification step (P2) is carried out at least once at the end of at least one step (ii).

[0317] Preferably, the purification (P) is carried out at least once between the reaction step (i) and at least one reaction step (ii).

[0318] In other words, when at least one step ii) exists, the purification step (P) can be carried out at least before and / or at least after the reaction step(s) (ii), preferably at least before the reaction step(s) (ii).

[0319] Preferably, the purification (P) is carried out at least once at the end of the reaction step (i).

[0320] When several steps i) are implemented in the process, at least one purification (P) can be carried out at the end of each of the steps i), or at least one purification step (P) can be carried out only at the end of the last step i).

[0321] According to the present invention, the purification (P) comprises at least one step (PI) and at least one step (P2) as defined previously.

[0322] Preferably, step(s) (PI) is or are carried out at a pH value greater than or equal to the pKa of the compound corresponding to the following formula (IV'): 9

[0323] or at a pH value greater than or equal to the lowest pKa of the compounds of formula (IV') if several compounds are present; formula (IV') being as described above, i.e. formula (IV') in which R2 has the same meaning as in formula (IV1).

[0324] Preferably, the treatment step(s) (PI) of the reaction medium resulting from the reaction steps (i) is or are carried out in a pH range from 3 to 8, more preferably from 4 to 8.

[0325] Preferably, at the end of the electrodialysis step (P2), the content of compound(s) of formula (IV1) is less than or equal to 10% by weight, preferably is less than or equal to 5% by weight, more preferably varies from 1 to 5% by weight, better still varies from 1 to 2% by weight, relative to the total weight of the dry extract containing said compound of formula (I). Additional purification steps

[0326] The purification (P) may further comprise one or more additional steps, different from steps (PI) and (P2).

[0327] The purification (P), carried out in an aqueous reaction medium comprising at least the compound of formula (IV1), may comprise, simultaneously or sequentially, preferably sequentially, in particular before or after the treatment step (PI), in particular before the treatment step (PI), at least one neutralization step (PO) of all or part of the excess alkaline agent present in the reaction medium resulting from step (i).

[0328] Preferably, the at least one purification (P), carried out in an aqueous reaction medium, comprises: • at least one treatment step (PO) to neutralize all or part of the excess alkaline agent present in the reaction medium resulting from at least one step (i), • at least one treatment step (PI) of the reaction medium resulting from step (i) with at least one cationic ion exchange resin, as defined previously, carried out at a pH value greater than or equal to the pKa of the compound of formula (IV') or greater than or equal to the lowest pKa of the compounds of formula (IV') if several are present, • at least one electrodialysis step (P2) of the aqueous reaction medium comprising at least the compound of formula (IV1) • optionally at least one separation step (P'0) of the compound(s) of formula (III) present in the reaction medium at the end of the reaction(s) (i).

[0329] The purification step (P) optionally further comprises at least one step of activating the cationic ion exchange resin so that it is in acid form.

[0330] The resin activation step can be carried out before the neutralization step (PO) and / or before the treatment step (PI).

[0331] According to one embodiment, the neutralization step (PO) is carried out with at least one cationic ion exchange resin at a pH value higher than or equal to the pKa of the compound of formula (IV') or by adding at least one acidifying agent, organic or mineral, preferably mineral and more preferably chosen from the group consisting of mineral acids as described above, in the reaction medium resulting from step (i).

[0332] Preferably, the neutralization step (PO) of all or part of the excess alkaline agent is carried out with at least one cationic ion exchange resin at a pH value greater than or equal to the pKa of the compound of formula (IV') or at a value greater than or equal to the lowest pKa of said compounds of formula (IV'), preferably in a pH range from 1.5 to 6, preferably from 2 to 4.5, more preferably from 2 to 3.5, better still in a pH range from 2.5 to 3.5.

[0333] The cationic ion exchange resin, capable of being used during the treatment step (PO), may be identical or different, preferably identical to that used in the treatment step (PI).

[0334] Alternatively, the neutralization step (PO) of all or part of the at least one alkaline agent can be carried out by adding at least one acidifying agent, organic or mineral, preferably mineral, to the reaction medium resulting from step (i).

[0335] Preferably, the separation step (P'0) of the compound of formula (III) is carried out after the neutralization step (PO).

[0336] More preferably, the separation step (P'0) of the compound of formula (III) can be carried out by distillation.

[0337] Before the possible implementation of at least one reaction step (ii), the pH of the reaction medium can be modified by adding at least one mineral acidifying agent or an alkaline, mineral or organic agent.

[0338] Preferably, the pH of the reaction medium can be modified by adding at least one mineral acidifying agent, in particular of the mineral acid type such as sulfuric acid, phosphoric acid, sulfonic acid, phosphonic acid, H+Hal acids, with Hal representing a halogen atom chosen from the group consisting of chlorine, bromine and iodine, more preferably the acidifying agent is hydrochloric acid. Reaction step (ii)

[0339] The preparation process may optionally further comprise at least one reaction step (ii) of at least said compound of formula (I) in which X corresponds to a divalent radical -C(O)- (i.e. a compound of formula (IA)) to form at least one compound of formula (I) in which X corresponds to a divalent radical -CH(OR)- (i.e. a compound of formula (IB)).

[0340] According to an advantageous embodiment, the process according to the invention further comprises at least one reaction step (ii) of at least said compound of formula (IA) to form at least one compound of formula (IB). Reduction step (iil)

[0341] The reaction step (ii) is preferably a reduction step (iii) taking place in an aqueous medium according to the following synthesis route (B): Reduction SA' .............................* SA'^ i O O H CIA) (TB)

[0342] synthesis route (B) in which: • SA' and RI have the same meanings as in formula (I).

[0343] For the purposes of the present invention, a compound of formula (IB) is a compound of formula (IB) in which R represents a hydrogen atom.

[0344] In other words, a compound of formula (I) is a compound of formula (I) in which X corresponds to a divalent radical -CH(OR)- with R representing a hydrogen atom.

[0345] Preferably, the preparation process according to the invention comprises: - at least one reaction step (i), as described previously, - at least one reduction step (ii), taking place in an aqueous medium according to the synthesis route (B) as defined previously, - at least one purification step (P), as described previously, carried out before and / or after the reduction step (ii).

[0346] The step of reducing the carbonyl group to produce an alcohol group is carried out by a conventional reduction method known to those skilled in the art. For example, the work (Adv. Or g. Chem. J. March, 4th ed. John Wiley & son, p. 910-919, (1992) may be cited. The at least one reduction step (ii) may be a reduction carried out in the presence of one or more hydrides, in particular borohydrides such as NaBH4, NaBH3CN, an enzymatic reduction or a reduction by catalytic hydrogenation.

[0347] Preferably, the at least one reduction step (iil) is a reduction by catalytic hydrogenation.

[0348] In other words, the at least one reduction step (iil) is advantageously a hydrogenation carried out in the presence of at least one catalyst and optionally an acidifying agent. The hydrogenation can for example be carried out under conditions described in the literature Heterocycles M. Hashimoto, M. Takahashi 77 (1), 227-231 (2009).

[0349] The catalyst is preferably a metal catalyst, such as ruthenium (Ru), rhodium (Rh), platinum (Pt), iridium (Ir), nickel (Ni) or palladium (Pd), preferably ruthenium (Ru) more preferably a metal catalyst, chosen from ruthenium (Ru), rhodium (Rh), Platinum (Pt), Iridium (Ir), better ruthenium (Ru).

[0350] Preferably, the catalyst is supported, preferably is ruthenium supported, such as on carbon (or graphite), on alumina, on AISi, on zeolite, or on barium sulfate (BaSO4).

[0351] According to one embodiment, the hydrogenation is catalyzed by Pd on carbon (Pd / C) or Ru on carbon (Ru / C).

[0352] Preferably, the catalyst is selected from the group consisting of ruthenium on carbon (Ru / C), ruthenium on alumina (Ru / Al), ruthenium on AISi, ruthenium on zeolite or ruthenium on barium sulfate (BaSO4).

[0353] Preferably, the catalyst is ruthenium (Ru), in particular on carbon (Ru / C).

[0354] Preferably, at least one reduction step (ül) is carried out under a hydrogen pressure ranging from 2 to 100 bars, preferably ranging from 3 to 50 bars, more preferably ranging from 4 to 25 bars, even more preferably ranging from 5 to 15 bars, better still ranging from 6 to 12 bars, such as 10 bars.

[0355] Preferably, the at least one reduction step (ül) is carried out at a temperature ranging from 30 to 150°C, preferably at a temperature ranging from 40 to 100°C, more preferably at a temperature ranging from 65°C to 100°C.

[0356] Preferably, the at least one reduction step (ül) takes place over a period ranging from 30 minutes to 30 hours, preferably from 45 minutes to 10 hours, in particular ranging from 1 hour to 7 hours.

[0357] Preferably, the at least one reduction step (ül) is a reduction by catalytic hydrogenation in the presence of at least one catalyst, in particular ruthenium, under a hydrogen pressure ranging from 2 to 100 bars and at a temperature ranging from 30 to 150°C.

[0358] Preferably, the at least one reduction step (ül) is a reduction by catalytic hydrogenation in the presence of at least one catalyst, in particular ruthenium, under a hydrogen pressure ranging from 2 to 50 bars and at a temperature ranging from 40 to 100°C.

[0359] Preferably, the at least one reduction step (ül) is a reduction by catalytic hydrogenation in the presence of at least one catalyst, in particular ruthenium, under a hydrogen pressure ranging from 2 to 25 bars and at a temperature ranging from 65°C to 100°C.

[0360] Advantageously, the at least one reduction step (ül) is carried out, in an aqueous medium: - in the presence of: of at least one compound of formula (I), in which X corresponds to a divalent radical -C(0)-, • at least one catalyst, more preferably chosen from the group consisting of palladium or ruthenium, in particular ruthenium on carbon, - under a hydrogen pressure varying from 2 to 50 bars, more preferably from 4 to 12 bars, such as 10 bars; - at a temperature ranging from 40 to 100°C, preferably at a temperature ranging from 65 to 120°C.

[0361] At the end of at least one reduction step (iiil), the reaction medium can be cooled to a temperature varying from 15 to 25°C and then purged under nitrogen.

[0362] The reaction medium resulting from step (iil) is then preferably filtered.

[0363] Preferably, the preparation process according to the invention comprises succes sively: • at least one reduction step (iil) as defined previously, • preferably, the reaction medium before, during or at the end of the reduction step (iil) undergoes at least one treatment with carbon black, more preferably before or after the reduction step (iil), in particular before the reduction step (iil) the reaction medium undergoes at least one treatment with carbon black, optionally at a temperature which can range from 20°C to 90°C, • optionally, at least one step of adding at least one acidifying or alkalizing agent to the reaction medium resulting from the reduction step (ii), • optionally, at least one concentration step (iil) of the compound of formula (IB) in the reaction medium resulting from the reduction step (iil), • preferably the concentration step (iil) is carried out by distillation, preferably under reduced pressure, • optionally, at least one purification step such as filtration, • optionally, at least one step (iv) of adding at least one bac agent tericidal or bacteriostatic, preferably bacteriostatic, preferably derived from glycol such as propylene glycol, pentylene glycol, caprylyl glycol, • preferably, the bacteriostatic agent, in particular propylene glycol, is present in a content ranging from 2 to 50% by weight, preferably from 5 to 40% by weight, relative to the total weight of the mixture comprising at least the compound of formula (IB), and the bacteriostatic agent, • possibly, at least one purification step such as a dis-

[0364]

[0365]

[0366]

[0367]

[0368]

[0369]

[0370]

[0371]

[0372] tillation. For the purposes of the present invention, the term "bio-sourced" means that the compounds described as "bio-sourced" are derived from compounds of plant origin. Addition step (ii2) The reaction step (ii) can also be an addition or O-alkoxylation step (ii2) taking place in an aqueous or non-aqueous medium, according to the following synthesis route (Bl): Y ............................* SA'^ J OH QB (FB) (I”B) synthesis route (Bl) in which: R corresponds to a C1-C10 alkyl group, preferably C1-C4, such as methyl, or a C1-C4 alkylcarbonyl group such as acetyl. Advantageously, the method according to the invention comprises: - at least one step (i) as defined above, - at least one reaction step (ii) corresponding to a reduction step (iil), as defined above, - at least one reaction step (ii) corresponding to an addition step (ii2), as defined previously, - at least one purification (P), as defined previously, carried out at least between the reaction step (i) and the reduction step (ii11), and / or at least after the reduction step (ii11), preferably between the reduction step (i) and the addition step (ii2), and / or after the addition step (ii2). For the purposes of the present invention, a compound of formula (IB) is a compound of formula (IB) in which R represents a hydrogen atom. In other words, a compound of formula (I) is a compound of formula (I) in which X corresponds to a radical -CH(OR) with R representing a hydrogen atom. Preferably, the preparation process according to the invention comprises: - at least one reaction step (i), as described previously, - at least one reduction step (iil), taking place in an aqueous medium according to the synthesis route (B) as defined previously, - at least one treatment step (PI) and at least one electrodialysis step (P2), as described previously, the electrodialysis step (P2) being carried out before and / or after the reduction step (iil), preferably before the reduction step (iil). The reduction step (iil) may be a reduction carried out in the presence of one or several hydrides, such as NaBH4, NABH3CN, enzymatic reduction or reduction by catalytic hydrogenation.

[0373] Preferably, the reduction step (iil) is a reduction by catalytic hydrogenation.

[0374] In other words, the reduction step (ii) is advantageously a hydrogenation carried out in the presence of at least one catalyst.

[0375] The catalyst is preferably a metal catalyst, such as ruthenium (Ru) or palladium (Pd), preferably ruthenium (Ru).

[0376] Preferably, the catalyst is supported, preferably is ruthenium supported, such as on carbon, on alumina, on AISi, on zeolite, or on barium sulfate (BaSO4).

[0377] Preferably, the catalyst is selected from the group consisting of ruthenium on carbon (Ru / C), ruthenium on alumina (Ru / Al), ruthenium on AISi, ruthenium on zeolite or ruthenium on barium sulfate (BaSO4).

[0378] Preferably, the catalyst is ruthenium (Ru), for example on carbon (Ru / C).

[0379] Preferably, the at least one reduction step (iil) is carried out under a hydrogen pressure ranging from 2 to 100 bars, preferably ranging from 3 to 50 bars, more preferably ranging from 4 to 25 bars, even more preferably ranging from 5 to 15 bars, better still ranging from 6 to 12 bars, such as 10 bars.

[0380] Preferably, the at least one reduction step (iil) is carried out at a temperature ranging from 30 to 150°C, preferably at a temperature ranging from 40 to 100°C, more preferably at a temperature ranging from 65°C to 100°C.

[0381] Preferably, the at least one reduction step (iil) takes place over a period ranging from 30 minutes to 30 hours, preferably from 45 minutes to 10 hours, in particular ranging from 1 hour to 7 hours.

[0382] Preferably, the at least one reduction step (ii) is a reduction by catalytic hydrogenation in the presence of at least one catalyst, in particular ruthenium, under a hydrogen pressure ranging from 2 to 100 bars and at a temperature ranging from 30 to 150°C.

[0383] Preferably, the at least one reduction step (ii) is a reduction by catalytic hydrogenation in the presence of at least one catalyst, in particular ruthenium, under a hydrogen pressure ranging from 2 to 50 bars and at a temperature ranging from 40 to 100°C.

[0384] Preferably, the at least one reduction step (ii) is a reduction by catalytic hydrogenation in the presence of at least one catalyst, in particular ruthenium, under a hydrogen pressure ranging from 2 to 25 bars and at a temperature ranging from 65°C to 100°C.

[0385] Preferably, the at least one reduction step (ül) is a reduction by catalytic hydrogenation in the presence of at least one catalyst, in particular ruthenium, under a hydrogen pressure ranging from 5 to 25 bars and at a temperature ranging from 65°C to 100°C.

[0386] Advantageously, the reduction step (ii) is carried out in an aqueous medium: - in the presence of: • at least one compound of formula (I), in which X corresponds to a -CO radical, • at least one catalyst, more preferably chosen from the group consisting of palladium or ruthenium, in particular ruthenium on carbon, - under a hydrogen pressure varying from 2 to 50 bars, preferably from 5 to 50 bars, more preferably from 4 to 12 bars, in particular from 8 to 12 bars, - at a temperature ranging from 40 to 100°C, preferably at a temperature ranging from 65 to 120°C.

[0387] At the end of the reduction step (iiil), the reaction medium can be cooled to a temperature varying from 15 to 25°C and then purged under nitrogen.

[0388] The reaction medium resulting from step (iil) is then preferably filtered.

[0389] Preferably, the method according to the invention comprises: • at least one reduction step (iil) as defined previously, • preferably, the reaction medium undergoes at least one treatment with carbon black, more preferably before or after the reduction step (ii), in particular before the reduction step, optionally at a temperature which can range from 20 to 90°C, • optionally, at least one step of adding at least one acidifying or alkalizing agent to the reaction medium resulting from the reduction step (ii), preferably a step of adding at least one acidifying agent, in particular mineral, in particular of the H+Hal type with Hal representing a halogen atom chosen from the group consisting of chlorine, bromine and iodine, more preferably the acidifying agent is hydrochloric acid, • optionally, at least one concentration step (iil) of the compound of formula (IB) in the reaction medium resulting from the reduction step (iil), • preferably the concentration step (iil) is carried out by distillation, preferably under reduced pressure, • optionally, at least one sterilizing filtration step, preferably a 0.2 pm filtration step, • optionally, at least one step (iii) of adding at least one bac agent tericidal or bacteriostatic, preferably bacteriostatic, preferably propylene glycol, in particular propylene glycol of biosourced origin, • preferably, the bacteriostatic agent in particular propylene glycol, is present in a content ranging from 2 to 50% by weight, preferably from 5 to 40% by weight, relative to the total weight of the mixture comprising at least the compound of formula (IB), and the bacteriostatic agent, • possibly, at least one distillation step, in particular of bio-sourced propylene glycol.

[0390] For the purposes of the present invention, the term “bio-sourced” means that the propylene glycol is derived from compounds of plant origin. Addition step (ii2)

[0391] The reaction step (ii) can also be an addition step (ii2) taking place in an aqueous medium according to the following synthesis route (Bl): SA*' [ ---------------------------* OH OS (l'B) fT'B)

[0392]

[0393]

[0394] synthesis route (Bl) in which: R corresponds to a C1-C10 alkyl group, preferably C1-C4, such as methyl, or a C1-C4 alkylcarbonyl group such as acetyl. Advantageously, the method according to the invention comprises: - at least one step (i) as defined above, - at least one reaction step (ii) corresponding to a reduction step (iil), as defined above, - at least one reaction step (ii) corresponding to an addition step (ii2), as defined previously, - at least one treatment step (PI) and at least one electrodialysis step (P2), as described previously, the electrodialysis step (P2) being carried out before and / or after the reduction step (ii11), preferably between the reduction step (ii11) and the addition step (ii2). According to another variant of the invention, the compounds (I”B) are obtained by addition of at least one molar equivalent of at least one nucleophilic compound RG to at least one compound of formula (IA), with R as defined above and G represents an electrodeficient atom or group such as an alkali metal such as sodium, potassium, or lithium, or a magnesium halide such as MgCl in particular this reaction is carried out under an inert atmosphere and in a preferably polar aprotic organic solvent, particularly an ethereal solvent such as diethyl ether, THF, followed by a hydrolysis reaction. Conditioning of the compound of formula (I)

[0395] At the end of the process according to the invention, the compound of formula (I), in which X corresponds to a divalent radical -C(O)- or -CH(OR)-, can be packaged in the form of a dry extract (without solvent).

[0396] Preferably, at the end of the process according to the invention, the compound of formula (I), in which X corresponds to a divalent radical -C(O)- or -CH(OR)-, is in solution in a liquid which comprises a content of at least 25% by weight of active material of the compound of formula (I), preferably in a content ranging from 25 to 80% by weight, more preferably ranging from 25 to 75% by weight, more preferably ranging from 30 to 75% relative to the total weight of the solution.

[0397] Preferably, at the end of the process according to the invention, the compound of formula (I), in which X corresponds to a divalent radical -C(O)- or -CH(OR)-, is in solution in a liquid which comprises a content of at least 25% by weight of active material (I), more preferably in a content ranging from 25 to 45% by weight relative to the total weight of the solution.

[0398] Preferably, at the end of the process according to the invention, the compound of formula (I), in which X corresponds to a radical -C(O)- or -CH(OR), is in solution in a liquid which comprises a content of at least 25% by weight of active material, more preferably in a content ranging from 25% to 75% by weight relative to the total weight of the solution.

[0399] According to one embodiment, the compound of formula (I) in which X corresponds to a divalent radical -C(O)- or -CH(OR)- is packaged in a liquid and the pH is adjusted to a target value, preferably between 3.5 and 7, by adding at least one alkalizing agent or at least one acidifying agent. Chemical structure(s)

[0400] SA' may represent a monosaccharide group or a polysaccharide group comprising up to 6 sugar units, in pyranose and / or furanose form and of L and / or D series, of anomer a or b, and comprising at least one free hydroxy group, and optionally at least one optionally protected amine group.

[0401] Preferably, SA' represents a monosaccharide or a polysaccharide comprising up to 6 sugar units, in pyranose and / or furanose form and of L and / or D series, and comprising at least one free hydroxy group.

[0402] According to one embodiment, SA' is a monosaccharide group selected from the group consisting of glucose, galactose, mannose, xylose, fucose, arabinose, rhamnose, glucuronic acid, galacturonic acid, iduronic acid, N-acetyl-glucosamine, N-acetyl-galactosamine and more particularly lirement SA is a monosaccharide selected from the group consisting of D-glucose, D-galactose, D-mannose, D-xylose, L-fucose, L-arabinose, L-rhamnose, D-glucuronic acid, D-galacturonic acid, D-iduronic acid, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine.

[0403] Preferably, SA' is a monosaccharide selected from the group consisting of glucose, xylose, N-acetyl-galactosamine or fucose, in particular glucose, xylose or fucose, more particularly xylose.

[0404] More preferably, SA' is a monosaccharide group chosen from the group consisting of D-glucose, D-xylose, N-acetyl-D-galactosamine or L-fucose, in particular D-glucose, D-xylose or L-fucose, more particularly D-xylose.

[0405] According to one embodiment, SA' is a polysaccharide group comprising up to 6 sucrose units and chosen from the group consisting of D-maltose, D-lactose, D-cellobiose, D-maltotriose, a disaccharide combining a uronic acid chosen from D-iduronic acid or D-glucuronic acid with a hexosamine chosen from D-galactosamine, D-glucosamine, N-acetyl-D-galactosamine, N-acetyl-D-glucosamine, an oligosaccharide containing at least one xylose advantageously chosen from xylobiose, methyl-beta-xylobioside, xylotriose, xylotetraose, xylopentaose and xylohexaose and preferentially xylobiose which is composed of two xylose molecules linked by a beta-1-4 bond.

[0406] Preferably, SA' represents a monosaccharide.

[0407] Preferably, SA' represents a monosaccharide group chosen from the group consisting of glucose, in particular D-glucose, xylose, in particular D-xylose, fucose, in particular L-fucose, arabinose, in particular L-arabinose, rhamnose, in particular L-rhamnose, glucuronic acid, in particular D-glucuronic acid, galacturonic acid, in particular D-galacturonic acid, iduronic acid, in particular D-iduronic acid, N-acetyl glucosamine, in particular N-acetyl-D-glucosamine, N-acetyl-galactosamine, in particular N-acetyl-D-galactosamine and preferably SA is chosen from D-glucose, D-xylose, L-fucose, L-arabinose, L-rhamnose, D-glucuronic acid, D-galacturonic acid, D-iduronic acid.

[0408] Preferably, SA' represents a monosaccharide group chosen from the group consisting of glucose, xylose, N-acetyl-galactosamine or fucose, more preferably SA' is chosen from the group consisting of glucose, xylose or fucose.

[0409] Preferably, SA' represents a monosaccharide group chosen from the group consisting of D-glucose, D-xylose, N-acetyl-D-galactosamine or L-fucose, more preferably SA is chosen from the group consisting of D-glucose, D-xylose or L-fucose.

[0410] More preferably, SA' represents a xylose group and even more preferably D-xylose.

[0411] As indicated previously, Ri represents a linear or branched, saturated or unsaturated, cyclic or acyclic hydrocarbon chain, in C1-C10, preferably in C1-C6, more preferably in C1-C4, in particular in Cp

[0412] According to one embodiment, Ri represents a linear or branched, saturated or unsaturated, cyclic or acyclic, preferably acyclic, C1-C6, more preferably C1-C4, in particular Cp, hydrocarbon chain.

[0413] According to one embodiment, Ri represents a linear or branched, saturated or unsaturated, cyclic hydrocarbon chain such as cyclohexyl or cyclopentyl, or acyclic in C1-C6, more preferably in C1-C4, in particular in Cp

[0414] Preferably, Ri represents a linear or branched, preferably linear, saturated or unsaturated, acyclic hydrocarbon chain, in C1-C10, preferably in C1-C6, more preferably in C1-C4, in particular in Cp

[0415] Preferably, Ri represents a linear, saturated or unsaturated, acyclic hydrocarbon chain, C1-C10, preferably C1-C6, more preferably C1-C4, in particular Cp

[0416] Preferably, Ri represents a linear, saturated or unsaturated, acyclic alkyl chain, in CrC4, in particular in Cp

[0417] Preferably, X represents a divalent radical -C(O)- or CH(OH)-.

[0418] Advantageously, in formula (I): - X represents a divalent radical -C(O)- or -CH(OH)-, - SA' represents a monosaccharide group selected from the group consisting of D-glucose, D-galactose, D-mannose, D-xylose, L-fucose, L-arabinose, L-rhamnose, D-glucuronic acid, D-galacturonic acid, D-iduronic acid, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, preferably selected from D-glucose, D-galactose, D-mannose, D-xylose, L-fucose, L-arabinose, L-rhamnose, D-glucuronic acid, D-galacturonic acid, D-iduronic acid, more preferably selected from D-glucose, D-xylose or L-fucose; - Ri represents a linear, saturated or unsaturated, acyclic hydrocarbon chain, C1-C10, preferably C1-C6, more preferably C1-C4, in particular a methyl group.

[0419] According to one embodiment, in formula (III), R 1 and R 2 are identical, and represent a linear or branched, saturated or unsaturated, cyclic or acyclic, preferably acyclic, C 1-C 6, more preferably C 1-C 4, in particular C 1-C 6, hydrocarbon chain.

[0420] Preferably, in formula (III), R1 and R2 are identical, and represent a linear or branched, saturated or unsaturated, acyclic hydrocarbon chain, in C1-C6, more preferably in C1-C4, in particular in Cp

[0421] Preferably, in formula (III), R1 and R2 are identical, and represent a linear, saturated or unsaturated, acyclic hydrocarbon chain, C1-C4, in particular C1.

[0422] According to one embodiment, in formula (IV1), R2 represents a linear or branched, saturated or unsaturated, cyclic or acyclic, preferably acyclic, C1-C6, more preferably C1-C4, in particular Cp, hydrocarbon chain.

[0423] Preferably, in formula (IV1), R2 represents a linear or branched, saturated or unsaturated, acyclic hydrocarbon chain, in C1-C6, more preferably in C1-C4, in particular in Cp

[0424] Preferably, in formula (IV1), R2 represents a linear, saturated or unsaturated, acyclic hydrocarbon chain, in CrC4, in particular in Cp

[0425] Preferably, in formulas (I), (III) and (IV1), R1 and R2 are identical, and represent a linear, saturated or unsaturated, acyclic hydrocarbon chain, in C1-C10, preferably in C1-C4, in particular in Cp

[0426] According to one embodiment, in formula (IV1), D+ may be an organic cation, preferably chosen from the group consisting of ammonium, phosphonium, imadazolium, pyrazolium, piperidinium, piperazinium ions.

[0427] According to one embodiment, in formula (IV1), D+ is an inorganic cation chosen from the group consisting of alkali metal cations and alkaline earth metal cations.

[0428] Advantageously, in formula (IV1), D+ is a cation chosen from the group consisting of alkali metal cations, alkaline earth metal cations, the ammonium ion (NH4+), in particular alkali metal cations, alkaline earth metal cations.

[0429] Preferably, in formula (IV1), D+ is a cation chosen from the group consisting of calcium ion (Ca2+), magnesium ion (Mg2+), sodium ion (Na+) and potassium ion (K+), in particular calcium ion and sodium ion, more particularly sodium ion.

[0430] Advantageously, SA' corresponds to the following formula (II'): (II')

[0431]

[0432]

[0433]

[0434]

[0435] Formula (II') in which the index n is equal to 0 or 1, preferably is equal to 1 and the index p is an integer varying from 1 to 4, preferably the index p is equal to 3. Preferably, in formula (II'), n is equal to 1 and p is an integer ranging from 1 to 4, preferably the index p is equal to 3. More preferably, in formula (II'), n is equal to 1 and p is equal to 3. The process for preparing at least one compound of formula (I) is preferably a process for preparing at least one compound of the following formula (I'):

[0436]

[0437]

[0438]

[0439] (D Formula (F) in which: - n is equal to 0 or 1, preferably is equal to 1, - p is an integer ranging from 1 to 4, preferably the index p is equal to 3, - RI has the same meaning as in formula (I), preferably re has a linear hydrocarbon chain, preferably acyclic, in CrC 10, preferably in Ci-C6, more preferably in Ci-C4, in particular in ci; - X represents a divalent radical -C(O)- or -CH(OR)-, - R represents a hydrogen atom, a CrCio alkyl group, of preferably C1-C4, such as methyl, or an alkyl(CrC4)carbonyl group such as acetyl; preferably R represents a hydrogen atom, as well as one of its optical isomers, geometric isomers, and / or one of its solvates such as hydrates; said method comprising: - at least one reaction step (i) taking place according to the following synthesis scheme (A'): L 'Y 0 § YxSîYYSS!': ..-■■■ Y'-""'' YsY ' , :■ t Y' dh û Ys” $ * (no OW Wi) synthesis route (A') in which: • n is equal to 0 or 1, preferably is equal to 1, • p is an integer ranging from 1 to 4, preferably the index p is equal to 3, • Ri and R2 are the same or different, preferably the same; with R2 having the same meaning as Ri in the formula (!'), • D is an organic or inorganic cation, preferably inorganic, more preferably chosen from the group consisting of alkali metal cations, alkaline earth metal cations and ammonium (NH4+); better still from the group consisting of alkali metal cations, alkaline earth metal cations;

[0440] said reaction step (i) being carried out in an aqueous medium in the presence of: • at least one compound of formula (II'), • at least one compound of formula (III), preferably present in a equimolar or excess quantity relative to the compound of formula (II'), preferably in excess, • preferably, the molar ratio compound(s) of formula (III) / compound(s) of formula (II') is greater than or equal to 1, preferably between 1 and 5, more preferably between 1 and 4, even more particularly between 1 and 3, better still between 1 and 2, in particular ranging from 1 to 1.5; according to a particular embodiment, the molar ratio compound(s) of formula (III) / compound(s) of formula (II') is greater than 1, • at least one alkaline agent in a molar quantity in excess, preferably in excess, relative to the compound of formula (II'), • preferably, the molar ratio of alkaline agent(s) / compound(s) of formula (II') is greater than or equal to 1, preferably between 1 and 5, more preferably between 1 and 4, even more particularly between 1 and 3, better still between 1 and 2; according to a particular embodiment, the molar ratio of alkaline agent / compound of formula (II') is greater than 1 • the alkaline agent being preferably mineral, more preferably chosen from the group consisting of alkali or alkaline-earth metal hydroxides, alkali or alkaline-earth metal (bi)carbonates, and mixtures thereof; in particular alkali or alkaline-earth metal hydroxides, such as sodium hydroxide,

[0441] to lead to the formation of at least one compound of formula (Ai), and at least one compound of formula (IV1) in an aqueous medium;

[0442] - optionally, at least one reaction step (ii) of at least said compound of formula (l'Ai) to lead to at least one compound corresponding to the formula (l'Bl):

[0443]

[0444]

[0445]

[0446]

[0447] we Formula (I) in which the indices n, p and RI have the same meanings as in formula (I); • preferably, the reaction step (ii) is a reduction step (ii11), as defined previously, • at least one purification (P) of the reaction medium including at least said compound of formula (IV1), carried out in an aqueous medium, comprising: • at least one treatment step (PI), carried out with at least one cationic ion exchange resin, in the reaction medium resulting from the reaction step(s) (i), • at least one electrodialysis step (P2) of the aqueous reaction medium comprising at least one compound of formula (Ai) or (Bl) and at least one compound of formula (IV1); the electrodialysis step(s) (P2) preferably being carried out after the treatment step(s) (PI). The reaction step (i) and the purification (P), in particular steps (P1) and (P2), are as defined previously. Preferably, the purification (P) is carried out after the reaction step (i). Preferably, the purification (P) is carried out at least between the reaction step (i) and at least one reaction step (ii), and / or at least after at least one reaction step (ii), for example after one and / or two reaction steps (ii). Preferably, the purification (P) comprises a step (PI) and a step (P2); said step (P2) being carried out after step (PI). Preferably, the reaction step (ii) is a reduction step (iiil) taking place in an aqueous medium according to the following synthesis route (Bl): (the Ai) (TB1)

[0448] synthesis route (Bl) in which: the index p and Ri have the same meaning as in formula (I).

[0449] Preferably, the reduction step (ii) is a reduction by catalytic hydrogenation, as defined previously.

[0450] For the purposes of the present invention, a compound of formula (Ai) is a compound of formula (!') in which X corresponds to a divalent radical -C(O)-.

[0451] For the purposes of the present invention, a compound of formula (I'B 1) is a compound of formula (I') in which X corresponds to a divalent radical -CH(OH)-.

[0452] Preferably, the purification (P) is carried out at least between the reaction step (i), as described above, and the reduction step (ii), as described above.

[0453] More preferably still, the process for preparing at least one compound of formula (I) is a process for preparing at least one compound of the following formula (I”):

[0454] as well as one of its optical isomers, geometric isomers, and / or one of its solvates such as hydrates;

[0455] said method comprising: - at least one reaction step (i) taking place according to the following synthesis scheme (A”): OH (H”) jïii) (i”A) (iv”)

[0456] synthesis route (A”) in which: • D+ is a cation chosen from the group consisting of alkali metal cations, alkaline earth metal cations and ammonium (NH4+);

[0457] said reaction step (i) being carried out in an aqueous medium, in the presence of: • at least one compound of formula (III'), preferably present in an equimolar quantity or in excess relative to the compound of formula (II”), • preferably, the molar ratio compound(s) of formula (III) / compound(s) of formula (II”) is greater than or equal to 1, preferably between 1 and 5, more preferably between 1 and 4, even more particularly between 1 and 3, better still between 1 and 2, in particular ranging from 1 to 1.5; according to a particular embodiment, the molar ratio compound(s) of formula (III) / compound(s) of formula (II”) is greater than 1, • at least one alkaline agent in an equimolar or excess quantity relative to the compound of formula (II”), • preferably, the molar ratio of alkaline agent(s) / compound(s) of formula (II') is greater than or equal to 1, preferably between 1 and 5, more preferably between 1 and 4, even more particularly between 1 and 3, better still between 1 and 2; according to a particular embodiment, the molar ratio of alkaline agent / compound of formula (II) is greater than 1 • the alkaline agent being preferably mineral, more preferably chosen from the group consisting of alkali or alkaline earth metal hydroxides, in particular sodium hydroxide,

[0458] to lead to the formation of at least one compound of formula (I”A) and at least one compound of formula (IV”) in an aqueous medium;

[0459] - optionally, at least one reaction step (ii) of at least said compound of formula (I”A), to lead to at least one compound corresponding to the following formula (I”B): I OH (I”B) • preferably, the reaction step (ii) is a reduction step (ii11), as defined previously, • at least one purification (P) of the reaction medium including at least said compound of formula (IV”), carried out in an aqueous medium, comprising: • at least one treatment step (PI), carried out with at least one cationic ion exchange resin, in the aqueous reaction medium resulting from the reaction step(s) (i), • at least one electrodialysis step (P2) of said reaction medium; the electrodialysis step(s) (P2) preferably being carried out after the treatment step(s) (PI).

[0460] The reaction step (i) and the purification (P), in particular steps (P1) and (P2), are as defined previously.

[0461] Step (P2) is in particular carried out in an aqueous reaction medium comprising at least one compound of formula (I”A) or (I”B) and at least one compound of formula (IV”).

[0462] Preferably, the purification (P) is carried out after the reaction step (i).

[0463] Preferably, the purification (P) is carried out at least between the step of reaction (i) and at least one reaction step (ii), and / or at least after at least one reaction step (ii), for example after one and / or two reaction steps (ii).

[0464] The treatment step (PI) is carried out after the reaction step (i).

[0465] The electrodialysis step (P2) can be carried out before and / or after the reaction step (ii), in particular before and / or after the reduction step (ii11), preferably before the reaction step (ii1), in particular before the reduction step (ii11).

[0466] Preferably, the purification (P) comprises a step (PI) and a step (P2); said step (P2) being carried out after step (PI).

[0467] For the purposes of the present invention, a compound of formula (I” A) is a compound of formula (I”) in which X corresponds to a divalent radical -C(O)-.

[0468] For the purposes of the present invention, a compound of formula (I”B) is a compound of formula (I”) in which X corresponds to a divalent radical -CH(OH)-.

[0469] Preferably, the reaction step (ii) is a reduction step (iii) taking place in an aqueous medium according to the following synthesis route (B”): (The A) (T'B)

[0470] Preferably, the reduction step (iil) is a reduction by catalytic hydrogenation, as defined above.

[0471] Preferably, the purification (P) is carried out at least between the reaction step (i) and at least one reduction step (iil), and / or at least after at least one reduction step (iil), for example after one and / or two reaction steps (ii).

[0472] Preferably, the purification (P) is carried out at least between the reaction step (i) and the reduction step (ii).

[0473] The process for preparing at least one compound of formula (!') or (I”) may further comprising the additional steps described for the process for preparing at least one compound of formula (I).

[0474] The invention is illustrated in more detail in the following non-limiting examples. Examples:

[0475] Example 1 - Preparation of CBD-xylopyranoside-2-hydroxy-propane (47% by weight)

[0476] Step 1: Preparation of a compound of formula (I”)

[0477] Water (1.04 kg) is loaded into a reactor at 20°C. It is heated to 50°C then xylose (700 g) is loaded and stirred until the medium is homogeneous.

[0478] Cool to a temperature of 15°C and charge the acetylacetone (555 g). Charge the 50% sodium hydroxide solution (540 g) at a temperature below 45°C. Then heat at 30 to 50°C for 30 min to 4 hours. Cool to 20°C and then pass through the strong sulfonic ion exchange resin until the pH is between 4.0 and 8.0. The acetylacetone is optionally distilled under vacuum at a temperature below 70°C.

[0479] At least one passage is then carried out on electrodialysis until an acetic acid content of less than 10,000 ppm or even less than or equal to 6000 ppm and a dry extract of 30% to 60% are obtained.

[0480] The solution is then brought into contact with carbon black and then optionally concentrated to a dry extract of 30% to 60% and then the pH is adjusted to 6.0-7.0.

[0481] The product is isolated with a yield of 90-95%.

[0482] Step 2: Catalytic hydrogenation to obtain the compound of formula (1'1)

[0483] The compound of formula (!') (2.08 kg) in aqueous solution with the appropriate acetic acid content is introduced into a hydrogenator with ruthenium on carbon (catalytic amount). The mixture is purged at least once with nitrogen and then with hydrogen. The mixture can be heated to a temperature above 25°C and then pressurized hydrogen is introduced up to a pressure of approximately 10 bars.

[0484] The mixture is heated to a temperature less than or equal to 100°C for a period of time ranging from 2 to 7 hours under a pressure ranging from 8 to 12 bars.

[0485] The hydrogenation reaction is carried out until the end of hydrogen consumption.

[0486] The reaction medium can be allowed to return to room temperature (20°C) and then is optionally purged with an inert gas (nitrogen). The catalyst is then filtered and the filtrate is then optionally brought into contact with carbon black. The solution is concentrated until a dry extract of 40 to 80% is obtained.

[0487] The pH of the filtrate is adjusted to acidic pH (for example between 4 and 6).

[0488] A glycol derivative as a solvent such as propylene glycol to obtain a content of compound of formula (I) of 20 to 90%.

[0489] The product is isolated in solution with a good yield (between 90-95%) and an acetic acid content of the solution of less than 20,000 ppm.

Claims

Claims

1. Process for purifying (PU) at least one aqueous medium comprising: - at least one cosmetic ingredient, and - at least one salt; said method comprising the implementation with: • at least one cationic ion exchange resin (PI) and • at least one electrodialysis (P2).

2. Purification process according to the preceding claim in which the cosmetic ingredient(s) is(are) chosen from the compounds of the following formula (I): (I) Formula (I) in which: - SA' represents a monosaccharide group or a polysaccharide group comprising up to 20 sugar units, in particular up to 6 sugar units, in pyranose and / or furanose form and of L and / or D series, said monosaccharide group or polysaccharide group having at least one free substituted hydroxy group, and optionally at least one optionally protected amine group, - the bond between SA' and CH2-X is a C-anomeric bond, - X represents a divalent radical -C(O)- or -CH(OR)-, preferably -C(O)- or -CH(OH)-; - R represents a hydrogen atom, a C1-C10 alkyl group, preferably C1-C4, such as methyl, or a (C1-C4)alkylcarbonyl group such as acetyl, preferably a hydrogen atom; - Ri represents a hydrocarbon chain, saturated or unsaturated, linear or branched, cyclic or acyclic, preferably acyclic, in C1-C10, preferably in C1-C4, more preferably saturated; particularly Ri represents a chain

3.

4.

5. linear or branched, saturated or unsaturated, cyclic or acyclic hydrocarbon, in C1-C10, more particularly in C1-C6, even more preferably in C1-C4, such as in C1; as well as their optical isomers, geometric isomers, and / or one of their solvates such as hydrates. Method according to the preceding claim, characterized in that SA' represents a monosaccharide group chosen from the group consisting of glucose, in particular D-glucose, xylose, in particular D-xylose, fucose, in particular L-fucose, arabinoqe, in particular L-arabinose, rhamnose, in particular L-rhamnose, glucuronic acid, in particular D-glucuronic acid, galacturonic acid, in particular D-galacturonic acid, iduronic acid, in particular D-iduronic acid, N-acetyl glucosamine, in particular N-acetyl-D-glucosamine, N-acetyl-galactosamine, in particular N-acetyl-D-galactosamine, and preferably SA is chosen from D-glucose, D-xylose, L-fucose, L-arabinose, L-rhamnose, D-glucuronic acid, D-galacturonic acid, D-iduronic acid. Process according to any one of claims 2 or 3, characterized in that Ri represents a linear, saturated or unsaturated, acyclic hydrocarbon chain, C1-C6, more preferably C1-C4, in particular C1. Method according to any one of the preceding claims, characterized in that the cosmetic ingredient(s) represent a compound of formula (I”): 0 X" X'-- HOX OH (I”) formula (I”) in which Ri and X are as defined in any one of claims 2, 4 or 5, as well as one of its optical isomers, geometric isomers, and / or one of its solvates such as hydrates; preferably of formula (!'”):

6. (I'”) Formula (I'”) in which: X corresponds to a divalent radical -C(O)- or -(CH)OH-, preferably -C(O)- as well as one of its optical isomers, geometric isomers, and / or one of its solvates such as hydrates. Process according to any one of the preceding claims, characterized in that said salt corresponds to the following formula (IV): Zÿ*A-(IV) Formula (II) in which: y is an integer ranging from 1 to 3, preferably 1; w is an integer ranging from 1 to 3, preferably 1; A is an organic or inorganic anion, preferably organic, more preferably chosen from the group consisting of CrCi8, even more preferably Ci-Cio, better still Ci-C6 carboxylic acids; D is an organic or inorganic cation, preferably inorganic, more preferably chosen from the group consisting of alkali metal cations, alkaline earth metal cations and ammonium (NH4+); preferably salt of formula (IV) corresponds to the following formula (IV1): (IV1) Formula (IV1) in which: D is an organic or inorganic cationic, preferably inorganic, R2 represents a linear, saturated or unsaturated hydrocarbon chain or branched, cyclic or acychic, preferably acychic, in C1-C10, preferably in C1-C6, more preferably in C1-C4, in particular in C1.

7. Purification method according to any one of the preceding claims in which the step of implementation with at least one cationic ion exchange resin (PI) is carried out before the electrodialysis (P2).

8. Method according to any one of the preceding claims, characterized in that the treatment step(s) (PI) are carried out with at least one cationic resin having carboxylic groups and / or at least one sulfonic resin, preferably at least one sulfonic resin.

9. Method according to any one of the preceding claims, characterized in that the electrodialysis step (P2) is carried out at a pH between 4 and 9, more preferably between 4.5 and 8.

5.

10. Method according to any one of the preceding claims, characterized in that the electrodialysis step (P2) is carried out at a temperature ranging from 20°C to 50°C, preferably at a temperature ranging from 25°C to 45°C.

11. Method according to any one of the preceding claims, characterized in that the electrodialysis step (P2) is carried out with conventional electrolysis, preferably at a product conductivity, before treatment, ranging from 50 to 0.05 mS / cm, preferably ranging from 40 to 0.2 mS / cm, measured in particular at a temperature ranging from 20°C to 50°C.

12. Method according to any one of the preceding claims, characterized in that the electrodialysis step (P2) is carried out with bipolar membrane electrolysis at a product conductivity (before treatment) ranging from 60 to 0.5 mS / cm, preferably ranging from 55 to 1 mS / cm, more preferably ranging from 50 to 10 mS / cm, even more preferably ranging from 45 to 20 mS / cm, measured in particular at a temperature ranging from 20°C to 50°C.

13. Method according to any one of the preceding claims using at least one alkaline agent.

14. A process for the preparation of at least one compound of formula (I) as defined in any one of claims 2 to 5 comprising: at least one reaction step (i) proceeding according to the scheme of synthesis (A) following: (he) (IA) (IV1) synthesis route (A) in which: • Ri and R2 are the same or different; with R2 having the same meaning as Ri in formula (I), • SA' has the same meaning as in formula (I), • D+ is an organic or inorganic cation derived from the alkaline agent, preferably D+ is an inorganic cation; said reaction step (i) being carried out in aqueous media in the presence of: • at least one compound of formula (II), • at least one compound of formula (III), and • at least one alkaline agent in an equimolar or excess quantity relative to the compound of formula (II), preferably or in excess, to lead to the formation of at least one compound of formula (IA) and at least one compound of formula (IV1) in an aqueous medium; - optionally, at least one reaction step (ii) of at least said compound of formula (IA), in a preferably aqueous medium, to lead to the formation of at least one compound corresponding to the following formula (IB): SA'' 7 GOLD (IB) Formula (IB) in which: SA', Ri and R have the same meanings as in formula (i); - at least one purification (P) of the reaction medium including at least said compound of formula (IV1), carried out in an aqueous medium, comprising: • at least one treatment step (PI), carried out with at least one cationic ion exchange resin, in the aqueous reaction medium resulting from said reaction step(s) (i), • at least one electrodialysis step (P2) of said aqueous reaction medium comprising at least said compound of formula (IA) or (IB) and at least the compound of formula (IV1); said electrodialysis step(s) (P2) being carried out after said treatment step(s) (PI).

15. Process according to the preceding claim, characterized in that the reaction step (i) is carried out in an aqueous medium in the presence of: • at least one compound of formula (II), • at least one compound of formula (III), • preferably, the molar ratio compound(s) of formula (III) / compound(s) of formula (II) is greater than or equal to 1, preferably between 1 and 5, more preferably between 1 and 4, even more particularly between 1 and 3, better still between 1 and 2, in particular ranging from 1 to 1.5; more particularly, the molar ratio compound(s) of formula (III) / compound(s) of formula (II) is greater than 1; • at least one mineral alkaline agent, preferably chosen from the group consisting of alkali or alkaline-earth metal hydroxides, alkali or alkaline-earth metal (bi)carbonates, and mixtures thereof; in particular alkali or alkaline-earth metal hydroxides, such as sodium hydroxide, • the alkaline agent being in an equimolar or excess quantity, preferably the molar ratio alkaline agent(s) / compound(s) of formula (II) is greater or equal to 1, preferably between 1 and 5, more preferably between 1 and 4, even more particularly between 1 and 3, better still between 1 and 2, • preferably, the reaction step (i) takes place: • at a temperature ranging from 20°C to 80°C, preferably at a temperature ranging from 20°C to 70°C, more preferably at a temperature ranging from 30°C to 70°C, better still from 30°C to 60°C, even better still at a temperature ranging from 35°C to 45°C • preferably, the reaction time varies: • from 10 minutes to 10 hours, preferably from 20 minutes to 5 hours, more preferably from 30 minutes to 4 hours, even more preferably from 45 minutes to 3 hours.

16. Method according to claim 14 or 15, characterized in that the purification(s) (P) can be carried out at least once between a reaction step (i) and at least one reaction step (ii), and / or at least once after at least one reaction step (ii), preferably the purification (P) is carried out at least once at the end of the reaction step(s) (i).

17. Process according to any one of claims 14 to 16, characterized in that the treatment step(s) (PI) is or are carried out at a pH value greater than or equal to the pKa of the compound corresponding to the following formula (IV'): 0 IR / ' "OH W') or at a pH value greater than or equal to the lowest pKa of the compounds of formula (IV') if several compounds are present, Formula (IV') in which R2 has the same meaning as in formula (IV1) of claim 7.

18. Method according to any one of claims 13 to 17, characterized in that the treatment step (PI) of the reaction medium resulting from the or reaction steps (i) are carried out in a pH range from 3 to 8, more preferably from 4 to 8.

19. Method according to any one of claims 13 to 18, characterized in that, at the end of the electrodialysis step (P2), the content of compound(s) of formula (IV) is less than or equal to 10% by weight, preferably is less than or equal to 5% by weight, more preferably varies from 1 to 5% by weight, better still varies from 1 to 2% by weight, relative to the total weight of the dry extract containing said compound of formula (I).

20. Process according to any one of claims 13 to 19, characterized in that the purification (P) comprises, simultaneously or sequentially, preferably sequentially, in particular before or after the treatment step (PI), more preferably before the treatment step (PI), at least one neutralization step (PO) of all or part of the excess alkaline agent present in the reaction medium resulting from step (i).

21. Process according to any one of claims 13 to 20, characterized in that the at least one purification step (P), carried out in an aqueous reaction medium, comprises: • at least one treatment step (PO) to neutralize the excess alkaline agent present in the reaction medium resulting from the at least one step (i), • at least one treatment step (PI) of the reaction medium resulting from step (i) with at least one cationic ion exchange resin implemented at a pH value greater than or equal to the pKa of the compound of formula (IV') or greater than or equal to the lowest pKa of the compounds of formula (IV'), • at least one electrodialysis step (P2) of said aqueous reaction medium comprising at least the compound of formula (IV).

22. Process according to any one of claims 13 to 21, characterized in that it further comprises at least one reaction step (ii) of at least said compound of formula (IA) to lead to at least one compound of formula (IB).

23. Process according to the preceding claim, characterized in that the reaction step (ii) is a reduction step (iii) taking place in an aqueous medium according to the following synthesis route (B): Redudhn ► SA'" T ÔH (IA) (FB) synthetic route (B) in which: • SA' and RI have the same meanings as in formula (I).

24. Process according to claim 22 or 23, characterized in that the reaction step (ii) is at least one reduction step (ii) by catalytic hydrogenation, preferably carried out in the presence of at least one metal catalyst, more preferably ruthenium (Ru), rhodium (Rh), Platinum (Pt), Iridium (Ir), Nickel (Ni) or palladium (Pd), preferably ruthenium (Ru) more preferably a metal catalyst, chosen from ruthenium (Ru), rhodium (Rh), Platinum (Pt), Iridium (Ir), better still ruthenium (Ru).

25. Process according to any one of claims 13 to 24, characterized in that the compound of formula (I), in which X corresponds to a divalent radical -C(O)- or -CH(OR)-, is in solution in a liquid which comprises a content of at least 25% by weight of active material of the compound of formula (I), preferably in a content ranging from 25 to 80% by weight, more preferably ranging from 25 to 75% by weight, more preferably ranging from 30 to 75% relative to the total weight of the solution.

26. A method according to any one of the preceding claims, characterized in that D+ is a cation selected from the group consisting of alkali metal cations, alkaline earth metal cations, ammonium ion (NH4+), preferably alkali metal cations, alkaline earth metal cations, in particular from a group consisting of calcium ion (Ca2+), magnesium ion (Mg2+), sodium ion (Na+) and potassium ion (K+).