EP3233874A1 - Antibacterial composition containing an isomer mixture of monosaccharide alkyl monoacetals or monoethers - Google Patents

Abstract

The invention relates to a bactericidal or bacteriostatic composition comprising a mixture of isomers of monosaccharide alkyl monoacetals or monoethers, the use thereof in the treatment or prevention of infections involving Gram-positive bacteria, the use thereof as a hygiene or dermatological product for external use, as well as a method for disinfecting surfaces.

Description

 Antibacterial composition containing an isomeric mixture of alkyl monoethers or monoacetals of monosaccharides

Technical area

 The present invention relates to a bactericidal or bacteriostatic composition comprising a mixture of positional isomers of monoethers or alkyl monoacetals of monosaccharides, its use in the treatment or prevention of Gram-positive bacterial infections, its use as a product of hygiene or dermatological for external use as well as a method of disinfection of surfaces.

Technical background

 Antimicrobial compounds are defined as molecules that can inhibit or stop the growth of microorganisms or kill them. In this context, they are commonly used to prevent or treat human and animal infections, and in the agri-food industry to prevent the multiplication of pathogenic bacteria in foods. The wide range of use of antimicrobial compounds has promoted the emergence of resistant infectious agents. The spread of bacteria that have acquired resistance mechanisms to the most widely used antimicrobial compounds is a major public health problem that is increasingly alarming (JS Bradley et al., Lancet Infect, Dis 2007; 7:68 -78).

 By way of illustration, many antibiotic resistant strains of the most pathogenic species of the Staphylococcus genus, namely Staphylococcus aureus have been isolated. Staphylococcal infections represent a significant percentage of serious infections. In addition, almost half of nosocomial infections are linked to staphylococci. We can also mention the many strains of Enterococcus faecalis or Enterococcus faecium resistant to antibiotic agents commonly used. However, although they are less virulent compared to staphylococci in particular, there is an increasing number of strains of multidrug-resistant enterococci and more recently epidemics of enterococci resistant to glycopeptides, the antibiotics of recourse vis-à-vis this bacterial family.

Another antimicrobial resistance phenomenon has been described that may be related not only to the excessive use of antibiotics, but to the methods of preserving food. For example, Listeria monocytogenes has been shown to be more resistant to antibiotics after surviving osmotic stress, low temperature, or acidic conditions (Anas A. et al., (2015) Food Microbiology, Volume 46). , April, pages 154-160). However, human contamination is of food origin. In addition, although relatively rare, human listeriosis is a serious infection with an estimated mortality of 50%. Thus, the emergence of antibiotic resistance in L monocytogenes that could be induced by modern methods of food preservation or treatment poses a serious threat to public health.

 Although several mechanisms are often involved simultaneously in antibiotic resistance, it is common to classify them into three categories: (a) lack of penetration of the antibiotic into the bacterium, (b) inactivation or excretion of the antibiotic by antibiotics. bacterial enzymatic systems and (c) lack of affinity between bacterial target and antibiotic. These three categories of resistance mechanism have a structural component namely the mechanisms implemented are dependent on the structure of the molecule concerned.

 Thus, in order to obtain an antibiotic composition with reduced chances of allowing the development of a resistance, the inventors have envisaged the use of a composition containing a mixture of compounds having an antibiotic activity but having minor structural differences capable of reduce the chances of developing bacterial resistance. They thus envisaged a composition comprising an isomeric mixture of compounds having an antibiotic activity.

 The inventors have wished to develop an antibiotic composition which also has low toxicity and low environmental impact. A biodegradable antibiotic composition that can be obtained in large quantities from renewable resources, at low cost in order to be perfectly accessible for industrial application but also as effective as non-biobased antimicrobials.

 However, no process of the prior art makes it possible to obtain an isomeric mixture of low toxicity and low cost biobased compounds.

 Nevertheless, biosourced compounds have been described by the prior art. Thus, the prior art describes various compounds used as antimicrobials, among which fatty acids and their corresponding polyhydroxy esters, which are active against bacteria.

Gram positive and possessing long aliphatic chains. As an indication, one of the most active antimicrobials is monolaurin, a glycerol monoester having a C12 aliphatic chain. Its commercial name is LAURICIDIN®. This compound is used as a food additive for the purpose of inhibiting bacterial growth (E. Freese, CW Sheu, E. Galliers, Nature 1973, 241, 321-325, EGA Verhaegh, DL Marshall, D.H. J. Int.J. Food Microbiol 1996, 29, 403-410). Now, the As the ester function of monolaurin is esterase sensitive, this compound is rapidly degraded and has a low half-life.

 The prior art also describes antimicrobials derived from sugar considered particularly attractive because of their biodegradability, low toxicity and environmental impact.

 Examples of sugar-derived antimicrobials are sugar-derived esters which are also used industrially for antimicrobial applications because their raw materials and cost of production remain relatively low. For example, sorbitan caprylate described in International Patent Application WO2014 / 025413 may be mentioned in admixture with Hinokitiol in an antimicrobial formulation. According to this application, this formulation would make it possible to inhibit or kill gram-positive and negative bacteria, fungi and / or mycoses.

 The prior art also discloses the use of disaccharide esters as an antimicrobial agent in the food industry. Dodecanoyl sucrose is one of the most used. The latter would be particularly active against L. monocytogenes (M. Ferrer, J. Soliveri, FJ Plou, N. Lopez-Cortés, D. Reyes-Duarte, M. Christensen, JL Copa-Patino, A. Ballesteros, Enz. Tech., 2005, 36, 391-398). Nevertheless, it is also described as a weak inhibitor of S. aureus growth for hospital applications (JD Monk, LR, Beuchat, AK Hathcox, J. Appt Microbiol., 1996, 81, 7-18). . Thus, the sucrose ester has bacteriostatic properties (stops bacterial growth) but not bactericidal (kills bacteria).

 In addition, the synthesis of sugar esters has many disadvantages. Firstly, despite the low production cost, the synthesis of esters, more particularly for di- and trisaccharides, is problematic because of the high functionality of the sugars which leads to the formation of a mixture of mono-, di- and polyesters and the presence of polar solvent, such as dimethylformamide (DMF) and pyridine, is generally necessary in order to better solubilize the highly polar reagents. However, these solvents are classified as Carcinogenic, Mutagenic and Reprotoxic (CMR) and their use should be avoided. To solve this problem, enzymatic synthesis has been used but the need to place in a very diluted environment under these conditions makes the production limited.

Moreover, the ester functions of these compounds are easily hydrolysable by the esterases present in the cells. However, the molecules released following this hydrolysis, namely sugar and fatty acid, have no or few antimicrobial properties (the fatty acid being slightly active). This induces instability responsible for a reduction in the activity time of these compounds. Thus, in order to obtain an antibiotic composition that is not conducive to the development of a resistance comprising effective and stable antimicrobial agents, the invention proposes a mixture of positional isomers of monoethers or of monosaccharide alkyl monoacetals obtained in inexpensive conditions while being environmentally friendly and not hazardous for topical applications or ingestion.

Detailed description of the invention

 Bactericidal or bacteriostatic composition

 The invention relates to a bactericidal or bacteriostatic composition comprising a mixture of positional isomers of monoethers or monoacetals of monosaccharide alkyl or of a monosaccharide derivative, said monosaccharide derivative being a glycosylated and / or hydrogenated and / or dehydrated monosaccharide, said mixture of positional isomers of monoethers or monoacetals of monosaccharide alkyl or monosaccharide derivative being obtained by a process comprising the following steps:

 a) an acetalization or trans-acetalization of a monosaccharide or a monosaccharide derivative with an aliphatic aldehyde containing from 1 to 18 carbon atoms or the acetal thereof; b) optionally, catalytic hydrogenolysis of the acetal monosaccharide alkyl or monosaccharide derivative obtained in a) preferentially, without an acid catalyst, and

 c) recovering a mixture of positional isomers of monosaccharide alkyl monoethers or the monosaccharide derivative obtained in b) in which the alkyl group (R) comprises from 1 to

18 carbon atoms

 or

 recovering a mixture of positional isomers of monosaccharide alkyl monoacetals or of a monosaccharide derivative obtained in a) in which the alkyl group (R) comprises from 1 to

18 carbon atoms.

The invention relates advantageously to a bactericidal or bacteriostatic composition comprising a mixture of positional isomers of monoethers or monosaccharide alkyl monoacetals or of a monosaccharide derivative, said monosaccharide derivative being a glycosylated and / or hydrogenated monosaccharide and / or dehydrated, said mixture of positional isomers of monoethers or monoacetals of monosaccharide alkyl or monosaccharide derivative being obtained by a process comprising the following steps:

 a) optionally, dehydrating a monosaccharide or a monosaccharide derivative to obtain a monoanhydrosaccharide;

 b) acetalization or trans-acetalization of the monosaccharide or monoanhydrosaccharide or monosaccharide derivative obtained in a) by

 i. an aliphatic aldehyde containing from 1 to 18 carbon atoms, by acetalization, or

 ii. an acetal of an aliphatic aldehyde containing from 1 to 18 carbon atoms, by trans-acetalization;

 c) optionally, catalytic hydrogenolysis of the acetal alkyl monosaccharide or monosaccharide derivative obtained in b) preferentially, without an acid catalyst, and

 d) recovering a mixture of positional isomers of monosaccharide alkyl monoethers or of a monosaccharide derivative obtained in c) in which the alkyl group (R) comprises between 1 1 to 18 carbon atoms

 or

 recovering a mixture of positional isomers of monosaccharide alkyl monoacetals or of a monosaccharide derivative obtained in b) in which the alkyl group (R) comprises between 1 1 to 18 carbon atoms.

As used herein, the term "monosaccharide" refers to polyhydroxyaldehyde (aldose) or polyhydroxyketone (ketosis).

 Preferably, said monosaccharide unit has 6 carbon atoms, also referred to as "hexose". The term "hexose" refers to both aldohexoses, ketohexoses, their derivatives and the like.

Preferably, said hexose is selected from the group consisting of glucose, mannose, galactose, allose, altrose, gulose, idose and talose. According to one embodiment, the monosaccharide derivative is anhydrosaccharide or a sugar alcohol.

 An "anhydrosaccharide" is to be understood as a monosaccharide obtained by dehydration, by the removal of one or more water molecules from a corresponding mono-, di-, tri- or oligosaccharide or from a derived from a mono-, di-, tri- or oligo-saccharide such as a hydrogenated mono-, di-, tri- or oligosaccharide. An example of a suitable anhydrosaccharide may be a monoanhydrosaccharide such as a hexitane selected from the group consisting of 1,4-anhydro-D-sorbitol (1,4-arlitan or sorbitan); 1,5-anhydro-D-sorbitol (polygalitol); 3,6-anhydro-D-sorbitol (3,6-sorbitan); 1, 4 (3,6) - anhydro-D-mannitol (mannitan); 1,5-anhydro-D-mannitol (styracitol); 3,6-anhydro-D-galactitol; 1,5-anhydro-D-galactitol; 1,5-anhydro-D-talitol and 2,5-anhydro-L-iditol.

 The preferred hexitane is obtained by the dehydration of sorbitol to form, for example, 1,4-sorbitan, 3,6-sorbitan or 2,5-sorbitan.

 According to one embodiment, said monosaccharide derivative is a sugar-alcohol. As used herein, the term "sugar alcohol", also known as "polyol" refers to a hydrogenated form of monosaccharide whose carbonyl group (aldehyde or ketone) has been reduced to a primary or secondary hydroxyl . Said sugar-alcohol may be, for example, selected from the group consisting of erythritol, threitol, arabitol, ribitol, mannitol, sorbitol, galactitol, volemitol, isomalt, maltitol, lactitol, maltotriitol, maltotetretol and polyglycitol. Preferably, the sugar alcohol is a hexitol chosen for example from mannitol, sorbitol, galactitol and volemitol, more preferably sorbitol, xylitol or mannitol.

 According to one embodiment, the process according to the invention may comprise a step of dehydration of said monosaccharide in order to obtain a monoanhydrosaccharide, for example, when the monosaccharide derivative is a sugar-alcohol. Typically, the monosaccharide is melted before the dehydration step. The dehydration step can be carried out with a catalyst for example with an acid catalyst.

 According to the invention, the dehydration step is carried out under a hydrogen atmosphere at a pressure preferably of about 20 to 50 bar.

 Advantageously, the dehydration step is carried out at a temperature between 120 and 170 ° C, preferably between 130 and 140 ° C.

Typically, the monosaccharide derivative is purified after the dehydration step, for example by crystallization, recrystallization or chromatography. According to one embodiment, said monosaccharide derivative is a glycosylated monosaccharide, in other words an alkylglycoside.

 As used herein, the term "alkylglycoside" refers to a monosaccharide where the reducing moiety is bonded to an alkyl group by glycosylation, as described in the state of the art. Typically, the monosaccharide may be bonded to the alkyl group by an oxygen atom (an O-glycoside), a nitrogen atom (a glycosylamine), a sulfur atom (a thioglycoside), or a carbon atom (a C glycoside). The alkyl group may have a preferably varied chain length, the alkyl group is a C1-C4 alkyl group. An even more preferred alkyl group is methyl or ethyl. Typically, the alkyl glycoside is a hexoside. Alkyl glycosides may be, for example, chosen from a group consisting of methyl glucoside, ethyl glucoside, propyl glucoside, butyl glucoside, methyl xyloside, ethyl xyloside, propyl xyloside, butyl xyloside, methyl mannoside, ethyl mannoside, propyl mannoside, butyl mannoside, methyl galactoside, ethyl galactoside, propyl galactoside and butyl galactoside.

 According to the invention, the acetalization or trans-acetalization step comprises:

 i) optionally, a step of preheating said monosaccharide or said monosaccharide mixture, preferably at a temperature of between 70 and 130 ° C., typically between 90 and 110 ° C.,

 ii) a step of adding the aliphatic aldehyde or an aliphatic aldehyde derivative to said monosaccharide and

 iii) a step of adding a catalyst, preferably an acid catalyst.

 Typically, the acetal of an aliphatic aldehyde may be a di-alkyl acetal of the corresponding aldehyde. Di-methyl acetals and diethyl acetals are preferred.

 Step i) is particularly advantageous in that it can be carried out in the absence of a solvent.

Preferably, the acid catalyst used during the acetalization or trans-acetalization step and, if appropriate, during the dehydration step may be a homogeneous or heterogeneous acidic catalyst. The term "homogeneous" as used in the term "homogeneous acid catalyst" refers to a catalyst that is in the same phase (solid, liquid or gas) or in the same aggregate state as the reagent. Conversely, the term "heterogeneous" as used in the term "heterogeneous acid catalyst" refers to a catalyst that is in a different phase (solid, liquid or gas) than the reagents.

 Said acid catalyst used during the acetalization stage or trans-acetalization and optionally in the dehydration step may be independently selected from solid or liquid acids, organic or inorganic, solid acids being preferred. In particular, the preferred acid catalyst is selected from para-toluene sulfonic acid, methanesulfonic acid, camphorsulfonic acid (CSA) and sulfonic resins.

 Typically, the acetalization or trans-acetalisation step is carried out at temperatures between 70 and 130 ° C, typically between 70 and 90 ° C. The temperature of the reaction mixtures may vary depending on the reagents and solvents used. The reaction time is determined by the degree of conversion achieved.

 According to one embodiment, the step of acetalization or trans-acetalization can be carried out by an aliphatic aldehyde or the acetal thereof, typically a linear or branched aliphatic aldehyde or acetal thereof. The acetalization or trans-acetalization step may be typically carried out with an aliphatic aldehyde or the acetal thereof having 1 1, 12, 13, 14, 15, 16, 17 or 18 carbon atoms, for example selected from undecanal, dodecanal, tridecanal, tetradecanal, pentadecanal, hexadecanal, heptadecanal, octodecanal. Preferably, the C 1 -C 13 aliphatic aldehyde or acetal thereof is a C 12 aliphatic aldehyde or acetal thereof, for example, a dodecanal or acetal thereof.

 The term "acetal thereof" or "their acetal (s)" as used herein includes the di-alkyl acetal of the corresponding C1-C18 aliphatic aldehyde. More particularly, the di-methyl or di-ethyl acetals of the C 1 -C 18 aliphatic aldehyde are preferred.

 According to one embodiment, the acetalization or trans-acetalisation step can be carried out with or without a solvent. When the reaction is carried out in the presence of a solvent, the solvent is preferably a polar solvent.

Typically, the solvent may be chosen from dimethylformamide (DMF), dimethylsulfoxide (DMSO), dimethylacetamide (DMA), acetonitrile (CH ₃ CN), tetrahydrofuran (THF), 2-methyltetrahydrofuran (2Me-THF) cyclopentyl methyl ether (CPME), methanol (MeOH), ethanol (EtOH), propanol (PrOH), isopropanol (iPrOH), butanol (BuOH), dibutyl ether (DBE), methyl tert-butyl ether (MTBE) and trimethoxypropane (TMP).

 In-depth experimental work has led to a selection of conditions allowing the observation of conversion rates and optimal yields during the stages of acetalization or trans-acetalization. The best results have been obtained when the molar ratio "aliphatic aldehyde C1-C18 or their acetal: monosaccharide" is between 5: 1 and 1: 5, preferably between 4: 1 and 1: 4, and advantageously between 3: 1 and 1: 3.

 The inventors have shown more particularly that, during an acetalization reaction, the aliphatic aldehyde aliphatic C1-C18: monosaccharide molar ratio of between 1: 1 and 1: 5, preferably between 1: 1 and 1: 4, and preferably between 1: 3 and 1: 2 improves yields and provides optimal conversion rates.

 The inventors have furthermore shown that during the trans-acetalization reactions, a C 1 -C 18 aliphatic acetal molar ratio: monosaccharide of between 1: 1 and 5: 1, preferably between 5: 4 and 4: 1, preferably between 3: 1 and 4: 3, more preferably between 3: 2 and 2: 5 improves yields and provides optimal conversion rates. The catalysts used are the same as during the acetalization reaction.

 According to one embodiment, the method of the invention further comprises at least one neutralization and / or filtration and / or purification step after any of the dehydration steps, if any, of acetalization or trans - acetalization.

 When a purification step is provided, said purification step can be, for example, crystallization, recrystallization or chromatography. Preferably, the chromatography is carried out using a non-aqueous polar solvent. In general, when a filtration and / or purification step is provided before the hydrogenolysis step, the non-aqueous polar solvent may be identical to that used in the hydrogenolysis step.

 Advantageously, the hydrogenolysis step is carried out at a temperature of between 80 ° C. and 140 ° C., and / or at a hydrogen pressure of between 15 ° C. and 15 ° C.

50 bar, preferably between 20 and 40 bar.

The hydrogenolysis step is advantageously carried out in an aprotic polar solvent, preferably a non-aqueous solvent. Indeed, the aprotic solvents offer a better conversion. Examples of aprotic solvents are, among others, without limitation, alkanes, 1,2,3-trimethoxypropane (TMP), tert-butyl methyl ether (MTBE), tetrahydrofuran (THF), 2-methyl tetrahydrofuran (2Me-THF), dibutyl ether (DBE) and cyclopentyl methyl ether (CPME). Preferably, the aprotic solvent is CPME. Alkanes are advantageous because they allow better solubilization of hydrogen in the medium. However, the conversion is lower than other aprotic solvents such as CPME. In general, of the alkanes, dodecane and heptane are preferred.

 The hydrogenolysis step is preferably carried out in a polar aprotic solvent at a temperature of between 80 ° C. and 140 ° C. and / or under a hydrogen pressure of between 15 and 50 bar, in the presence of a suitable catalyst. to hydrogenolysis reactions.

 Preferably, the hydrogenolysis step is carried out in a non-aqueous polar solvent at a temperature of between 100 ° C. and 130 ° C. and / or at a pressure of between 25 and 35 bar.

 Generally, the hydrogenolysis is carried out in the presence of a suitable catalyst such as a catalyst based on precious metals or base metals. More particularly, the base metals can be ferrous or non-ferrous metals. Typically, the hydrogenolysis is carried out in the presence of a ferrous metal catalyst.

 As an indication, a metal catalyst belonging to the group of ferrous metals may be nickel, cobalt or iron.

 Preferably, the hydrogenolysis is carried out using a catalyst based on precious metals such as palladium, rhodium, ruthenium, platinum or iridium.

 As a rule, the catalyst used during the hydrogenolysis can be attached to a support such as carbon, alumina, zirconia or silica or any mixture thereof. Such a support is for example a ball. Thus, a palladium catalyst attached to charcoal (Pd / C) beads can be advantageously used. These catalysts can be doped by the addition of precious metals or common metals. We speak of doping agent. Typically, the doping agent is 1 to 10% by weight of the catalyst.

The invention also relates to a bactericidal or bacteriostatic composition comprising a mixture of positional isomers of monoethers or of monosaccharide alkyl monoacetals or of a monosaccharide derivative having an alkyl ether or alkyl acetal radical in two distinct positions of the monosaccharide or of the derivative of monosaccharide and the pharmaceutically acceptable salts thereof wherein the alkyl group comprises from 1 to 18 carbon atoms, preferably from 1 to 13 carbon atoms.

 The term "pharmaceutically acceptable salts" refers to any salt which upon administration to the patient is capable of providing (directly or indirectly) a compound such as that described herein. The preparation of salts can be carried out by methods known in the state of the art.

 Preferably, the monosaccharide is a C6 monosaccharide or derivative thereof, said monosaccharide derivative being a glycosylated and / or hydrogenated and / or dehydrated monosaccharide such as an alkylglycoside, preferentially, the monosaccharide or the monosaccharide derivative is:

 a hexose selected from the group consisting of glucose, mannose, galactose, allose, altrose, gulose, idose and talose,

 a hexitol chosen from mannitol, sorbitol, galactitol and volemitol; a hexitane chosen from 1,4-anhydro-D-sorbitol (1,4-arlitan or sorbitan);

 1,5-anhydro-D-sorbitol (polygalitol); 3,6-anhydro-D-sorbitol (3,6-sorbitan); 1, 4 (3,6) -anhydro-D-mannitol (mannitan); 1,5-anhydro-D-mannitol (styracitol); 3,6-anhydro-D-galactitol; 1,5-anhydro-D-galactitol; 1,5-anhydro-D-talitol and 2,5-anhydro-L-iditol or

 Typically, the alkyl glycoside is a hexoside selected from glucoside, mannoside, galactoside, alloside, altroside, iodoside and taloside.

 By "position isomer" is meant regioisomers, more particularly isomer of monoethers or monoacetals of monosaccharide alkyl or monosaccharide derivative in which the monoether or monoacetal radical of alkyl is positioned on different oxygens of the monosaccharide or of the monosaccharide derivative.

 Typically, when the monosaccharide is a hexoside, said monoacetal alkyl radical is at the 1, 2-0 position; 2,3-0-; 3,4-0- or 4,6-0- of the hexoside or when the monosaccharide derivative is hexitol, said monoacetal alkyl radical is at the 1,2-position; 2,3-0-; 3,4-0-; 4.5-0- or 5,6-0- of hexitol or when the monosaccharide derivative is a hexitane, said monoacetal alkyl radical is in position 2,3-0-; 3.5-0- or 5.6-0- hexitane.

Preferably, when the monosaccharide is a hexoside, said alkyl monoether radical is in the 2-0-, 3-0-, 4-0- or 6-0- position of the hexoside or when the monosaccharide derivative is a hexitol, said alkyl monoether radical is in the 1 - O-, 2-0-, 3-0-, 4-0-, 5-0- or 6-0- position of hexitol or when the monosaccharide derivative is a hexitane, said alkyl monoether radical is in the 2-0-, 3-0-, 5-0- or 6-0- position of hexitane.

 According to one variant, the monosaccharide derivative is a sorbitan and the said alkyl monoacetal radical is in the 3,5-O- or 5,6-O-position or the said alkyl mono-ether radical is in the 3-O-, 5-O- or 6-0-.

 According to one variant, the monosaccharide derivative is a glucoside and said monoacetal alkyl radical is in the position 4,6-O- or said alkyl monoether radical is in the 4-O- or 6-O-position.

Advantageously, the mixture of positional isomers of monosaccharide alkyl monoethers or of a monosaccharide derivative comprises at least one compound chosen from methyl 4,6-O-pentylidene α-D-glucopyranoside; methyl 4,6-O-hexylidene a-D-glucopyranoside; methyl 4,6-O-octylidene α-D-glucopyranoside, methyl 4,6-O-decylidene α-D-glucopyranoside; methyl 4,6-O-dodecylidene a-D-glucopyranoside; methyl 4,6-O-dodecylidene β-D-glucopyranoside; methyl 4,6-O-dodecylidene α-D-mannopyranoside; methyl 4,6-O-dodecylidene a-D-galactopyranoside and mixtures thereof.

 According to one embodiment, the mixture of positional isomers of monosaccharide alkyl monoacetals or of a monosaccharide derivative comprises at least methyl 6-O-pentyl-D-glucopyranoside and 4-O-pentyl-α. Methyl D-glucopyranoside; methyl 6-O-hexyl-D-glucopyranoside and methyl 4-O-hexyl-D-glucopyranoside; methyl 6-O-octyl-D-glucopyranoside and methyl 4-O-octyl-D-glucopyranoside; methyl 6-O-decyl α-D-glucopyranoside and methyl 4-O-decyl α-D-glucopyranoside, methyl 6-O-dodecyl α-D-glucopyranoside and 4-O-dodecyl α- Methyl D-glucopyranoside; methyl 6-O-dodecyl-D-mannopyranoside and methyl 4-O-dodecyl-D-mannopyranoside; methyl 6-O-dodecyl-α-D-galactopyranoside and methyl 4-O-dodecyl-α-D-galactopyranoside or mixtures thereof

 Typically, the composition is bactericidal or bacteriostatic with respect to Gram-positive bacteria.

Advantageously, the bactericidal or bacteriostatic composition is incorporated into a food, cosmetic, pharmaceutical, phytosanitary, veterinary or surface treatment composition. Such as for example, a composition cosmetic and / or dermatological cleaning and / or care for the skin, in particular in the form of a cream, a gel, a powder, a lotion, a butter in particular, a shower gel, soap, shampoo, shower bath , deodorant, antiperspirant, wet wipe, sunscreen formulation or decorative cosmetic formulation.

 The invention also relates to a use of a bactericidal or bacteriostatic composition according to the invention as a hygiene or dermatological product for external use.

 Typically a "hygiene product" refers to any product used for cleaning, disinfection or hygiene, including for example a lotion, mousse, spray and liquid but also wipes or any medium likely to be impregnated with the composition according to the invention. The term "dermatological product" refers to any product intended for application to the skin or mucous membranes.

Use in the treatment or prevention of Gram-positive bacterial infection.

 The invention further relates to a composition according to the invention for use in the treatment or prevention of bacterial infections by Gram-positive bacteria.

 By "treatment" is meant curative treatment (aimed at at least reducing, eradicating or halting the development of the infection) in a patient. By "prevention" is meant prophylactic treatment (aimed at reducing the risk of the onset of infection) in a patient.

 The "patient" may be, for example a human or a non-human mammal (for example a rodent (mouse, rat), a feline, a dog or a primate) affected by or likely to be affected by infections bacterial and in particular Gram positive. Preferably, the subject is a human.

 The term "Gram-positive" refers to bacteria that are stained in dark blue or purple by Gram staining, as opposed to gram-negative bacteria that can not retain the purple dye. The staining technique is based on the membrane and wall characteristics of the bacteria.

Typically, Gram-positive bacteria are bacteria of the branching of Firmicutes, typically of the Bacilli class, chosen especially from bacteria of the order Lactobacillales or Bacillales. According to one embodiment of the invention, the bacteria of the order Bacillales are chosen from the family of Alicyclobacillaceae, Bacillaceae, Caryophanaceae, Listeriaceae, Paenibacillaceae, Pasteuriaceae, Planococcaceae, Sporolactobacillaceae, Staphylococcaceae, Thermoactinomycetacea and Turicibacteraceae

 Typically, the bacteria of the Listeriaceae family are for example of the genus Brochothrix or Listeria and may be typically selected from L. fleischmannii, L. grayi, L. innocua, L. ivanovii, L. marthii, L. monocytogenes, L. rocourtiae, L. seeligeri, L. weihenstephanensis and L welshimeri.

 When the Gram-positive bacteria are bacteria of the Staphylococcaceae family, they are chosen in particular from the bacteria of the genus Staphylococcus, Gemella, Jeotgalicoccus, Macrococcus, Salinicoccus and Nosocomiicoccus.

 Bacteria of the genus Staphylococcus, for example chosen from S. arlettae, S. agnetis, S. aureus, S. auricularis, S. capitis, S. caprae, S. carnosus, S. caseolyticus, S. chromogenes, S. cohnii, S. condidenti, S. delphini, S. devriesei, S. epidermidis, S. equorum, S. felis, S. florettii, S. gallinarum, S. haemolyticus, S. hominis,

S. hyicus, S. intermedius, S. kloosii, S. leei, S. lentus, S. lugdunensis, S. lutrae, S. massiliensis, S. microti, S. muscae, S. nepalensis, S. pasteuri, S. Pettenkoferi, S. piscifermentans, S. pseud intermedius, S. pseudolugdunensis, S. pulvereri, S. rostri, S. saccharolyticus, S. saprophyticus, S. schleiferi, S. sciuri, S. simiae, S. simulans, S. stepanovicii , S. succinus, S. vitulinus, S. warneri and S. xylosus.

 According to another embodiment of the invention, the bacteria of the order Lactobacillales are selected from a family of Aerococcaceae, Carnobacteriaceae, Enterococcaceae, Lactobacillaceae, Leuconostocaceae and Streptococcaceae.

 Typically, the bacteria of the family Enterococcaceae are selected from bacteria of the genus Bavariicoccus, Catellicoccus, Enterococcus, Melissococcus, Pilibacter, Tetragenococcus, Vagococcus.

 Bacteria of the Enterococcus genus are chosen for example from E. malodoratus, E. avium, E. durans, E. faecalis, E. faecium, E. gallinarum, E. hirae, E. solitarius, preferably E. avium, E. durans, E. faecalis and E. faecium.

Bacteria of the genus Staphylococcus and more particularly S. aureus are responsible for many infections of the skin or mucous membranes such as the vaginal or nasal mucosa. For example, infections such as folliculitis, abscesses, paronychia, boils, impetigo, interdigital infections, anthrax (anthrax staphylococcal), cellulitis, superinfections of wounds, otitis sinusitis, hydradenitis, infectious mastitis, post-traumatic skin infections or burned skin infections.

 Bacteria of the Enterococcus genus including E. faecalis are responsible for endocarditis, bladder infections, prostate and epididymis

 The invention also relates to a method for treating or preventing a bacterial infection by Gram-positive bacteria, preferentially an infection of the skin or mucous membranes, by preferentially topical administration, to an individual in need thereof, a therapeutically effective amount of the composition according to the invention.

 In a person infected with a gram-positive bacterium, the term "therapeutically effective amount" means an amount sufficient to prevent the infection to progress to aggravation, or even sufficient to reduce the infection. In an uninfected person, the "therapeutically effective amount" is the amount sufficient to protect a person who is brought into contact with a Gram-positive bacterium and to prevent the occurrence of the infection caused by this gram-positive bacterium.

 Typically, topical administration is effected by application to the skin or to the mucous membranes of the composition according to the invention.

Method for disinfecting or preventing the bacterial colonization of a substrate

 The invention further relates to a method for disinfecting or preventing bacterial colonization by Gram-positive bacteria of a substrate comprising contacting the substrate with a composition according to the invention.

 Typically, the substrate is any medium likely to be colonized by Gram-positive bacteria and capable of transmitting the infection to an animal by contact or by ingestion.

 For example, the substrate may be a food of plant or animal origin or a food composition comprising such foods or an extract of these foods and in particular cereals, fruits, vegetables, meat, fish, offal.

The substrate may also be one or more elements selected from metals, plastics, glass, concrete, stone. Preferably the substrate is a utensil, a tool or a device used in the food industry, (kitchen utensils, containers, cold storage system, refrigerator, cold rooms ..) in a hospital environment, such as for example tools for surgery or prostheses or in public transport (transit bar, seats ...).

 The invention also relates to a composition for disinfecting, purifying, sterilizing or purifying surfaces.

 Although having distinct meanings, the terms "comprising", "containing", "comprising" and "consisting of" have been used interchangeably in the description of the invention, and may be replaced by other.

 The invention will be better understood on reading the following figures and examples given solely by way of example. Examples

 The sugar alkyl acetals (sorbitan and methyl glycopyranoside) were prepared by acetalization or transacetalization of the sugars according to the procedure previously described in the patent No. 13/01375 "Process for the preparation of long-chain alkyl cyclic acetals, based on of sugars ". The sugar alkyl acetals are then reduced using reducing conditions without acid catalyst previously described in the patent No. 14/01346. The method used is identical in the case of alkyl acetals of sorbitan and alkyl acetals of methyl glycopyranosides. As an indication, the synthesis of acetals and ethers is detailed below.

EXAMPLE 1 General Procedure for the Preparation of Alkyl Acetates of Methyl Glycopyranoside (A)

In a 100 ml flask under an argon atmosphere, methyl glycopyranoside (2 equivalents) is dissolved in dry THF (10 mL) in the presence of sodium sulfate (1.5 equivalents). The aldehyde (1 equivalent) is added dropwise over a period of one minute, followed by Amberlyst 15 (20% by weight relative to the aldehyde). The reaction mixture is magnetically stirred at reflux (65 ° C.) for 3 hours. After returning to ambient temperature, the reaction medium is filtered, washed with ethyl acetate (2 × 25 mL) and the filtrate is concentrated under reduced pressure. The residue is purified by silica gel column chromatography (AcOEt / cyclohexane) to give alkyl acetals of methyl glycopyranoside. Example 1a: Me

Methyl 4,6-O-Pentylidene α-D-glucopyranoside (1a): Compound 1a was prepared from methyl Γα-D-glucopyranoside (7.49 g, 38.5 mmol) and pentanal (1.64 g, 19 mmol) ) according to procedure (A). After reaction, the residue was purified by column chromatography on silica gel (80: 20 EtOAc / cyclohexane) to give (2.14 g, 43%) as a white solid. M.p. = 78 ° C; ¹ H NMR (300 MHz, CDCl ₃ ) δ _Η : 0.88 (3H, t, J = 7, CH ₃ alkyl), 1.21-1.44 (4H, m, 2 (CH ₂ ) alkyl), 1.52-1.72 (2H, m, CH ₂ alkyl), 2.80 (1H, d, J = 9, OH ³ ), 3.23 (1H, t, J = 9, H ³ ), 3.31 (1H, d, J = 2, OH ² ), 3.40 (3H, s, OCH 3), 3.48 (1H, t, J = 10, H ² ), 3.52-3.67 (2H, m, H ⁵ + H ⁶ ), 3.83 (1H, td, J = 9 and 2, H ⁴ ), 4.09 (1H, dd, J = 10 and 4, H ⁶ ), 4.52 (1H, t, J = 5, H ⁷ ), 4.73 (1H, d, J = 4, H ¹ ); ¹³ C NMR (75 MHz, CDCl 3): _C : 14.05 (CH ₃ ), 22.62 (CH ₂ ), 26.30 (CH ₂ ), 34.03 (CH ₂ ), 55.54 (OCH ₃ ), 62.62 (CH ⁵ ), 68.57 ( CH ₂ ⁶ ), 71.70 (CH ⁴ ), 72.98 (CH ² ), 80.47 (CH ³ ), 99.87 (CH ¹ ), 102.81 (CH ⁷ ). IR v _max : 3399 (OH), 2956, 2862, 1428, 1390, 1062, 1041, 989; HRMS (ESI ⁺ ) calcd for C ₂₁ H ₂₂ Na0 ₆ : 285.1309 [M + Na] ⁺ , found: 285.1315 (-2.2 ppm); Rf = 0.27 (EtOAc / cyclohexane 80:20).

Example 1b: e

Methyl 4,6-O-hexylidene α-D-glucopyranoside (1b): Compound 1b was prepared from methyl Γα-D-glucopyranoside (3.22 g, 16.6 mmol) and hexanal (0.83 g, 8.3 mmol) according to procedure (A). After reaction, the residue was purified by column chromatography on silica gel (EtOAc / cyclohexane 80:20) to give 1b (0.98 g, 43%) as a white solid. Mp = 84 ° C; ¹ H NMR (300

MHz, CDCl3) δ _Η : 0.86 (3H, t, J = 7, CH ₃ alkyl), 1.05-1.30 (4H, m, 2 (CH ₂ ) alkyl), 1.31-1.46 (2H, m, CH ₂ alkyl) , 1.52-1.74 (2H, m, CH ₂ alkyl), 3.02 (1H, br s, OH ³ ), 3.23 (1H, t, J = 9, H ³ ), 3.40 (3H, s, OCH 3), 3.47 ( 1H, t, J = 10, H ² ), 3.52-3.66 (2H, m, H ⁵ + H ⁶ ), 3.83 (1H, t, J = 9, H ⁴ ), 4.09 (1H, dd, J = 10 and 5, H ⁶ ), 4.52 (1H, t, J = 5, H ⁷ ), 4.72 (1H, d, J = 4, H ¹ ); ¹³ C NMR (75 MHz, CDCl 3): _C : 14.10 (CH ₃ ), 22.62 (CH ₂ ), 23.86 (CH ₂ ), 31.74 (CH ₂ ), 34.28 (CH ₂ ),

55.51 (OCH 3), 62.62 (CH ⁵ ), 68.56 (CH ₂ ⁶ ), 71.61 (CH ⁴ ), 72.95 (CH ² ), 80.49 (CH ³ ), 99.90 (CH ¹ ), 102.81 (CH ⁷ ); IR v _max : 3433 (OH), 2925 (-CH ₃ ), 2860 (-CH ₂ -), 1465, 1379, 1061, 983; HRMS (ESI ⁺⁾ calculated for Ci ₃ H ₂ 4Na0 _6: 299.1465 [M + Na] ^+; measured: 299.1464 (+0.4 ppm); Rf = 0.27 (80:20 EtOAc / cyclohexane).

Example 1c: ^e

Methyl 4,6-O-octylidene α-D-glucopyranoside (1c): Compound 1c was prepared from methyl Γα-D-glucopyranoside (3.22 g, 16.6 mmol) and octanal (1.06 g, 8.3 mmol) according to procedure (A). After reaction, the residue was purified by column chromatography on silica gel (EtOAc / cyclohexane 50:50) to give 1c (0.94 g, 37%) as a white solid. Melting point = 80 ° C; ¹ H NMR (300 MHz, CDCl ₃ ) δ _Η : 0.85 (3H, t, J = 7, CH ₃ alkyl), 1.07-1.31 (8H, m, 4 (CH ₂ ) alkyl), 1.32-1.47 (2H, m, CH ₂ alkyl), 1.50-1.73 (2H, m, CH ₂ alkyl), 3.02 (2H, br s, OH ² + OH ³ ), 3.23 (1H, t, J = 9, H ³ ), 3.40 (3H, s, OCH 3), 3.48 (1H, t, J = 10, H ² ), 3.52-3.67 (2H, m, H ⁵ ), 3.83 (1H, t, J = 9, H ⁴ ), 4.09 ( 1H, dd, J = 10 and 5, H ⁶ ), 4.52 (1H, t, J = 5, H ⁷ ), 4.72 (1H, d, J = 4, H ¹ ); ¹³ C NMR (75 MHz, CDCl 3) 5 _C 14.18 (CH _3), 22.73 (CH _2), 24.18 (CH _2), 29.26 (CH _2), 29.51 (CH _2), 31.85 (CH _2), 34.33 ( CH ₂ ), 55.53 (OCH ₃ ), 62.62 (CH ⁵ ), 68.56 (CH ₂ ⁶ ), 71.68 (CH ⁴ ), 72.97 (CH ² ), 80.48 (CH ³ ), 99.88 (CH ¹ ), 102.82 (CH ² ), ⁷ ); IR _max : 3368 (OH), 2924, 2857, 1465, 1378, 1128, 1090, 1064, 1037, 993; HRMS (ESI ⁺ ) calcd for C ₅ H ₂₈ Na0 ₆ : 327.1778 [M + Na] ⁺ ; measured: 327.1780 (-0.6 ppm); Rf = 0.21 (50:50 EtOAc / cyclohexane).

Example 1d: e

Methyl 4,6-O-decylidene α-D-glucopyranoside (1d): Compound 1d was prepared from methyl Γα-D-glucopyranoside (20 g, 102 mmol) and decanal (7.97 g, 51 mmol). ) according to procedure (A). After reaction, the residue was purified by silica gel column chromatography (80: 20 EtOAc / cyclohexane) to give 1d (7.48 g, 44%) as a white solid. M.p. = 72 ° C; ¹ H NMR (300 MHz, CDCl 3) δ _Η : 0.87 (3H, t, J = 7, CH ₃ alkyl), 1.16-1.32 (12H, m, 6 (CH ₂ ) alkyl), 1.33-1.45 (2H, m). , CH ₂ alkyl), 1.55-1.72 (2H, m, CH ₂ alkyl), 2.61 (2H, br s, OH ³ + OH ² ), 3.24 (1H, t, J = 9, H ³ ), 3.42 ( 3H, s, OCH ₃ ), 3.49 (1H, t, J = 10, H ² ), 3.53-3.68 (2H, m, H ⁵ ), 3.84 (1H, t, J).

= 9, H ⁴ ), 4.11 (1H, dd, J = 10 and 5, H ⁶ ), 4.53 (1H, t, J = 5, H ⁷ ), 4.74 (1H, d, J = 4, H ¹ ); ¹³ C NMR (75 MHz, CDCl 3): _C : 14.03 (CH ₃ ), 22.59 (CH ₂ ), 24.08 (CH ₂ ), 29.25 (CH ₂ ), 29.46 (CH ₂ ), 29.49 (2CH ₂ ), 31.82 (CH ₂ ), 34.19 (CH ₂ ), 55.20 (OCH ₃ ), 62.54 (CH ⁵ ), 68.43 (CH ₂ ⁶ ), 70.90 (CH ⁴ ), 72.65 (CH ² ) 80.53 (CH ³ ), 100.02 (CH ¹ ), 102.64 (CH ⁷ ); IR v _max : 3393 (OH), 2922, 2853, 1466, 1378, 1112, 1088, 1063, 1037, 990; HRMS (ESI ⁺ ) calcd for C ₁₇ H ₃₂ Na0 ₆ : 355.2091 [M + Na] ⁺ ; measured: 355.2102 (-3.2 ppm); Rf = 0.32 (80:20 EtOAc / cyclohexane).

Example 1 e: e

Methyl 4,6-O-Dodecylidene α-D-glucopyranoside (1e): Compound 1e was prepared from methyl Γα-D-glucopyranoside (3.22 g, 16.6 mmol) and dodecanal (1.52 g, 8.3 mmol) according to procedure (A). After reaction, the residue was purified by column chromatography on silica gel (EtOAc / cyclohexane 60:40) to give 1d (0.77 g, 26%) as a white solid. M.p. = 69 ° C; ¹ H NMR (300 MHz, CDCl ₃ ) δ _Η : 0.86 (3H, t, J = 7, CH ₃ ), 1 .17-1 .32 (16H, m, 8 CH ₂ ), 1 .33-1 .47 (2H, m, CH ₂ ), 1.53-1.74 (2H, m, CH ₂ ), 2.64 (2H, br s, OH ³ + OH ² ), 3.24 (1H, t, J = 9.0, CH ³ ), 3.41 (3H, s, OCH 3), 3.49-3.68 (3H, m, CH ⁵ + CH ⁶ + CH ² ), 3.84 (1H, t, J = 9.0, CH ⁴ ), 4.10 (1H). , dd, J = 10.0 and 5.0, CH ⁶ ), 4.52 (1H, t, J = 5.0, CH ⁷ ), 4.74 (1H, d, J = 4.0, CH ¹ ); ¹³ C NMR (75 MHz, CDCl 3): _C : 14.24 (CH ₃ ), 22.80 (CH ₂ ), 24.20 (CH ₂ ), 29.46 (CH ₂ ), 29.58 (CH ₂ ), 29.62 (CH ₂ ), 29.67 ( CH ₂ ), 29.74 (CH ₂ ), 29.76 (CH ₂ ), 32.03 (CH ₂ ), 34.36 (CH ₂ ), 55.57 (OCH 3), 62.63 (CH ⁵ ), 68.57 (CH ₂ ⁶ ), 71 .81 ( CH ⁴ ), 73.02 (CH ² ), 80.46 (CH ³ ), 99.85 (CH ¹ ), 102.84 (CH ⁷ ); IR v _max : 3388 (OH), 2921, 2852, 1466, 1378, 1089, 1063, 1037, 991; HRMS (ESI ⁺⁾ calculated for Ci ₉ H ₃ 6Na0 _6: 383.2404 [M + Na] ^+; measured: 383.2398 (+1.6 ppm); Rf = 0.30 (EtOAc / cyclohexane 60:40).

Example 1 f:

Methyl 4,6-O-Dodecylidene β-D-glucopyranoside (1 f): Compound 1f was prepared from methyl β-D-glucopyranoside (5.00 g, 25.7 mmol) and dodecanal (2.37 g, 12.8 g). mmol) according to procedure (A). After reaction, the residue was purified by silica gel column chromatography (EtOAc / cyclohexane, 30:70 to 50:50) to give 1f (1.30 g, 28%) as a white solid. . Mp = 84 ° C; ¹ H NMR (300 MHz, CDCl 3) δ _Η : 0.87 (3H, t, J = 6.7, CH ₃ ), 1.25 (16H, br s, 8 CH ₂ ), 1 .34-1 .45 (2H). , m, CH ₂ ), 1.53-1.73 (2H, m, CH ₂ ), 3.25-3.34 (2H, m, CH ² + CH ⁵ ), 3.44 (1H, dd, J = 9.0, 7.0, CH ³ ), 3.56 (4H, s, CH ₂ ⁶ + OCH ₃ ), 3.73 (1H, m, CH ⁴ ), 4.18 (1H, dd, J = 10.4, 4.4, CH ₂ ⁶ ), 4.28 (1H, d, J = 7.7, CH ¹ ), 4.54 (1H, t, J = 5.1, CH ⁷ ); ¹³ C NMR (75 MHz, CDCl ₃ ) _C : 14.13 (CH ₃ ), 22.70 (CH ₂ ), 24.14 (CH ₂ ), 29.35 (CH ₂ ), 29.45 (CH ₂ ), 29.50 (CH ₂ ), 29.56 (CH ₂ ), 29.63 (CH ₂ ), 29.65 (CH ₂ ), 31.92 (CH ₂ ), 34.23 (CH ₂ ), 55.51 (OCH ₃ ), 66.21 (CH ⁵ ), 68.21 (CH ₂ ⁶ ), 73.19 (CH ⁴ ), 74.61 (CH ² ), 80.00 (CH ³ ), 102.83 (CH ⁷ ), 104.07 (CH ¹ ); IR v _max : 3650 (OH), 2950, 2824, 2867, 2159, 2028, 1112; HRMS (ESI ⁺⁾ calcd for Ci9H ₃₆ Na0 _6: 383.2404 [M + Na] ^+; measured: 383.2395 (+2.3 ppm). Rf = 0.30 (EtOAc / cyclohexane 40:60)

Example 1 q:

Methyl 4,6-O-Dodecylidene α-D-mannopyranoside (1 g): Compound 1 g was prepared from methyl Γα-D-mannopyranoside (4.00 g, 20.5 mmol) and dodecanal (3.45 g, 18.7). mmol) according to procedure (A). After reaction, the reaction medium is concentrated under reduced pressure and dissolved in CH ₂ Cl ₂ . The organic phase is washed with water (3 x 100 ml), with a saturated NaCl solution (2 x 100 ml), dried (Na ₂ SO ₄ ) and concentrated under reduced pressure. The residue was purified by column chromatography on silica gel (EtOAc / cyclohexane, 20:80 to 50:50) to give 1 g (0.73 g, 11%) as a white solid. M.p. = 104 ° C; ¹ H NMR (300 MHz, CDCl ₃ ) δ _Η : 0.88 (3H, t, J = 6.9, CH ₃ ), 1.17-1.32 (16H, m, 8 CH ₂ ), 1.37-1. 42 (2H, m, CH ₂ ), 1.58-1.68 (2H, m, CH ₂ ), 3.37 (3H, s, OCH ₃ ), 3.53-3.72 (3H, m, CH ³ + CH ⁵ + CH ⁶ ), 3.98 (1H, dd, J = 9.0, 3.7, CH ² ), 4.13 (1H, dd, J = 3.6, 1, ⁴ , CH ⁴ ), 4.58 (1H, dd, J = 8.8; , 2.9, CH ⁶ ), 4.10 (1H, t, J = 5.1, CH ⁷ ), 4.73 (1H, d, J = 1, 3, CH ¹ ); ¹³ C NMR (75 MHz, CDCl ₃ ) _C : 14.13 (CH ₃ ), 22.69 (CH ₂ ), 24.10 (CH ₂ ), 29.35 (CH ₂ ), 29.46 (CH ₂ ), 29.51 (CH ₂ ), 29.56 (CH ₂ ), 29.63 (CH ₂ ), 29.65 (CH ₂ ), 31.92 (CH ₂ ), 34.40 (CH ₂ ), 55.05 (OCH ₃ ), 63.00 (CH ⁵ ), 68.38 (CH ₂ ⁶ ), 68.81 (CH ² ), 70.82 (CH ⁴ ), 78.23 (CH ³ ), 101.15 (CH ¹ ), 103.06 (CH ⁷ ); IR v _max : 3380 (OH), 2924, 2852, 1466, 1156, 1029, 682; HRMS (ESI ⁺⁾ calculated for Ci ₉ H ₃₆ Na0 _6: 383.2404 [M + Na] ^+; measured: 383.2396 (+2.2 ppm). Rf = 0.2 (cyclohexane / EtOAc, 70:30). Example 1

Methyl 4,6-O-Dodecylidene α-D-galactopyranoside (1 h): Compound 1 was prepared from methyl Γα-D-galactopyranoside (5.00 g, 25.7 mmol) and dodecanal (2.37 g, 1 g). 2.9 mmol) according to procedure (A). After reaction, the reaction medium is concentrated under reduced pressure to give 1 h (2.30 g, 45%) in the form of a white solid without purification by chromatography. M.p. = 1-15 ° C; ¹ H NMR (300 MHz, CDCl ₃ ) δ _Η : 0.89 (3H, t, J = 6.7, CH ₃ ), 1.15-1.50 (18H, m, 9 CH ₂ ), 1.61 -1 1.71 (2H, m, CH ₂ ), 3.45 (3H, s, OCH ₃ ), 3.61 (1H, app., CH ⁵ ), 3.77-3.94 (3H, m, CH ⁴ + CH ² CH ⁶ ). , 4.04 (1H, d, J = 2.5, H ³ ), 4.14 (1H, dd, J = 12.5, 1, 4, CH ⁶ ), 4.59 (1H, t, J = 5.2, CH ⁷ ), 4.91 (1H, d, J = 3.2, CH ¹ ); ¹³ C NMR (75 MHz, CDCl ₃ ): _C : 14.06 (CH ₃ ), 22.50 (CH ₂ ), 23.49 (CH ₂ ), 29.27 (CH ₂ ), 29.34 (CH ₂ ), 29.41 (CH ₂ ), 29.48; (CH ₂ ), 29.55 (CH ₂ ), 29.61 (CH ₂ ), 31.97 (CH ₂ ), 34.47 (CH ₂ ), 55.66 (OCH ₃ ), 62.45 (CH ⁵ ), 68.92 (CH ₂ ⁶ ), 69.82 (CH ² ), 69.92 (CH ⁴ ), 75.42 (CH ³ ), 100.1 (CH ⁷ ), 102.1 (CH ¹ ); IR v _max : 3414, 3328 (OH), 2916, 2850, 2160, 1121, 1032; HRMS (ESI ⁺⁾ calcd for Ci9H Na0 _{36 6} 383.2404 [M + Na] ^+; measured: 383.2389 (+4.0 ppm). Rf = 0.6 (EtOAc / cyclohexane, 60:40).

EXAMPLE 2: General Procedure for the Preparation of Mixture of Regioisomers of alkyl ethers of methyl glycopyranoside (B) In a 100 ml autoclave made of stainless steel, the alkyl acetal of methyl glycopyranoside (3 mmol) is dissolved in cyclopentyl methyl ether (CPME, 30 mL) and 5% -Pd / C (0.45 g, 5 mol% palladium) is then added. The reactor is sealed, purged three times with hydrogen and the hydrogen is introduced at a pressure of 30 bar. The reaction mixture is mechanically stirred and heated at 120 ° C for 15 hours. After cooling to room temperature, the hydrogen pressure is released and the reaction mixture is diluted in absolute ethanol (100 mL) and filtered (Millipore Durapore filter 0.01 μm). The filtrate is concentrated under reduced pressure to give the mixture of alkyl ether regioisomers of methyl glycopyranoside. Example 2a: ^Me

Methyl 6-O-Pentyl α-D-glucopyranoside (2a) and methyl 4-O-pentyl OC-D-glucopyranoside (2a '): Compounds 2a and 2a' were prepared from 4,6-O methyl pentylidene α-D-glucopyranoside 1 a (4.00 g, 15 mmol) according to the general procedure (B). A 70:30 mixture of 2a and 2a '(1.51 g, 38%) is obtained as a white paste. To facilitate the characterization of the compounds, the regioisomers of the mixture can be separated by chromatography on a column of silica gel (EtOAc / cyclohexane, from 50:50 to 100: 0 then EtOH / EtOAc 10:90). 2a: Colorless oil. ¹ H NMR (300 MHz, CDCl ₃ ) δ _Η : 0.84 (3H, t, J = 7, CH ₃ alkyl), 1 .14-1 .36 (4H, m, 2 (CH ₂ ) alkyl), 1. 41-68 (2H, m, CH ₂ alkyl), 3.34 (3H, s, OCH ₃ ), 3.40-3.82 (7H, m), 4.53- 4.81 (4H, m, anomeric CH + 30H); ¹³ C NMR (75 MHz, CDCl ₃ ) _C : 14.06 (CH ₃ ), 22.53 (CH ₂ ), 28.20 (CH ₂ ), 29.29 (CH ₂ ), 55.12 (OCH ₃ ), 70.20 (CH ₂ ), 70.57. (CH), 70.74 (CH), 71.91 (CH), 72.05 (CH ₂ ), 74.26 (CH), 99.56 (CH); IR v _max : 3382 (OH), 2929, 2861, 1455, 1363, 1192, 1144, 108, 1040, 900; HRMS (ESI ⁺ ) calcd for C ₂₁ H ₂₄ Na0 ₆ : 287.1465 [M + Na] ⁺ ; measured: 287.1467 (-0.8 ppm); Rf = 0.35 (EtOAc / EtOH 10: 1). 2a ': Colorless oil. ¹ H NMR (300 MHz, CDCl ₃ ) δ _Η : 0.86 (3H, t, J = 7, CH ₃ alkyl), 1 .16-1 .38 (4H, m, 2 (CH ₂ ) alkyl), 1. 42-1.66 (2H, m, CH ₂ alkyl), 3.16 (3H, br s, OH), 3.21 (1H, t, J = 10), 3.37 (3H, s, OCH ₃ ), 3.42-3.87 (7H, m), 4.71 (1H, d, J = 3, anomeric CH); ¹³ C NMR (75 MHz, CDCl ₃ ) _C : 14.1 1 (CH ₃ ), 22.61 (CH ₂ ), 28.26 (CH ₂ ), 30.05 (CH ₂ ), 55.32 (OCH ₃ ), 61.92 (CH ₂₎ ), 71.00 (CH), 72.61 (CH), 73.14 (CH ₂ ), 74.52 (CH), 77.86 (CH), 99.35 (CH); IR v _max : 3388 (OH), 2928, 2852, 1452, 1371, 1092, 1083, 1037, 931; HRMS (ESI ⁺ ) calcd for C ₂₁ H ₂₄ Na0 ₆ : 287.1465 [M + Na] ⁺ ; measured: 287.1465 (+0.2 ppm); Rf = 0.40 (EtOAc / EtOH 10: 1). Example 2b: ^e

Methyl 6-O-Hexyl α-D-glucopyranoside (2b) and methyl 4-O-hexyl α-D-glucopyranoside (2b '): Compounds 2b and 2b' were prepared from 4,6-O 1-methyl hexylidene α-D-glucopyranoside (5.50 g, 20 mmol) according to the general procedure (B). A 72:28 mixture of 2b and 2b '(2.18 g, 37%) was obtained as a colorless oil. To facilitate the characterization of the compounds, the regioisomers of the mixture can be separated by gel column chromatography silica (EtOAc / cyclohexane, 50:50 to 100: 0 then EtOH / EtOAc 10:90). 2b: Colorless oil. ¹ H NMR (300 MHz, CDCl ₃ ) δ _Η : 0.84 (3H, t, J = 7, CH ₃ alkyl), 1 .13-1 .38 (6H, m, 3 (CH ₂ ) alkyl), 1. 44-1.64 (2H, m, CH ₂ alkyl), 3.38 (3H, s, OCH ₃ ), 3.39-3.78 (8H, m), 4.53 (3H, br s, OH), 4.71 (1H, d , J = 4, CH-anomeric); ¹³ C NMR (75 MHz, CDCl ₃ ) _C 14.10 (CH ₃ ), 22.66 (CH ₂ ), 25.75 (CH ₂ ), 29.60 (CH ₂ ), 31.75 (CH ₂ ), 55.18 (OCH ₃ ) , 70.24 (CH ₂ ), 70.55 (CH), 70.79 (CH), 71.94 (CH), 72.13 (CH ₂ ), 74.28 (CH), 99.56 (CH); IR v _max : 3376 (OH), 2928, 2859, 1455, 1364, 1192, 1144, 1006, 1043, 900; HRMS (ESI ⁺⁾ calculated for Ci ₃ H ₂₆ Na0 _6: 301 .1622 [M + Na] ^+; measured: 301.1612 (+ 3.3 ppm); Rf = 0.32 (EtOAc / EtOH 10: 1). 2b ': Colorless oil. ¹ H NMR (300 MHz, CDCl ₃ ) δ _Η : 0.87 (3H, t, J = 7, CH ₃ alkyl), 1 .17-1 .40 (6H, m, 3 (CH ₂ ) alkyl), 1. 46-1.66 (2H, m, CH ₂ alkyl), 2.43-2.78 (3H, br s, OH), 3.23 (1H, t, J = 10), 3.39 (3H, s, OCH ₃ ), 3.48 (1H, dd, J = 10 and 4), 3.53-3.64 (2H, m), 3.64-3.91 (4H, m), 4.73 (1H, d, J = 4, CH-anomeric); ¹³ C NMR (75 MHz, CDCl ₃ ): _C : 14.16 (CH ₃ ), 22.72 (CH ₂ ), 25.83 (CH ₂ ), 30.38 (CH ₂ ), 31.80 (CH ₂ ), 55.41 (OCH ₃ ) , 62.05 (CH ₂ ), 71.00 (CH), 72.72 (CH), 73.24 (CH ₂ ), 74.80 (CH), 77.91 (CH), 99.27 (CH); IR v _max : 3395 (OH), 2927, 2852, 1456, 1365, 1192, 1114, 1027, 896; HRMS (ESI ⁺⁾ calculated for Ci ₃ H ₂₆ Na0 _6: 301 .1622 [M + Na] ^+; measured: 301.1610 (+4.0 ppm); Rf = 0.38 (EtOAc / EtOH 10: 1).

Example 2c:

6-O-Octyl α-D-glucopyranoside methyl (2c) and 4-O-octyl OC-D-glucopyranoside methyl (2c '): Compounds 2c and 2c' were prepared from 4,6-O α-octylidene α-D-glucopyranoside methyl 1 c (5.00 g, 16.4 mmol) according to the general procedure (B). A 75:25 mixture of 2c and 2c '(2.30 g, 40%) was obtained as a colorless oil. To facilitate the characterization of the compounds, the regioisomers of the mixture can be separated by chromatography on a column of silica gel (EtOAc / cyclohexane, from 50:50 to 100: 0 then EtOH / EtOAc 10:90). 2c: Colorless oil. ¹ H NMR (300 MHz, CDCl _{3) δ} Η: 0.86 (3H, t, J = 7, CH ₃ alkyl), 1 .15-1 .38 (10H, m, 5 (CH ₂₎ alkyl), 1. 48-1.68 (2H, m, CH ₂ alkyl), 3.40 (3H, s, OCH ₃ ), 3.42-3.92 (8H, m), 4.22 (3H, br s, OH), 4.73 (1H, d , J = 4, CH-anomeric); ¹³ C NMR (75 MHz, CDCl ₃ ): _C : 14.22 (CH ₃ ), 22.78 (CH ₂ ), 26.15 (CH ₂ ), 29.39 (CH ₂ ), 29.59 (CH ₂ ), 29.72 (CH ₂ ), 31 96 (CH ₂ ), 55.30 (OCH ₃ ), 70.44 (CH ₂ ), 71.12 (CH), 72.08 (CH), 72.24 (CH), 74.44 (CH ₂ ), 77.36 (CH), 99.60 (CH). ); IR v _max : 3371 (OH), 2923, 2854, 1456, 1365, 1,192, 1,144, 1,108, 1044, 900; HRMS (ESI ⁺ ) calcd for C ₅ H ₃₀ NaO ₆ : 329.1935 [M + Na] ⁺ ; measured: 329.1943 (-2.5 ppm); Rf = 0.26 (EtOAc / EtOH 10: 1). 2c ': White solid. ¹ H NMR (300 MHz, CDCl ₃ ) δ _Η : 0.86 (3H, t, J = 7, CH ₃ alkyl), 1 .09-1 .39 (10H, m, 5 (CH ₂ ) alkyl), 1 .43-1 .66 (2H, m, CH ₂ alkyl), 2.58 ( 3H, br s, OH), 3.23 (1H, t, J = 10); 3.39 (3H, s, OCH ₃ ), 3.48 (1H, dd, J = 10 and 4), 3.53- 3.64 (2H, m), 3.66-3.89 (4H, m), 4.73 (1H, d, J). = 4, CH-anomeric); ¹³ C NMR (75 MHz, CDCl ₃ ) _C : 14.20 (CH ₃ ), 22.76 (CH ₂ ), 26.18 (CH ₂ ), 29.37 (CH ₂ ), 29.58 (CH ₂ ), 30.44 (CH ₂ ), 31 93 (CH ₂ ), 55.41 (OCH ₃ ), 62.08 (CH ₂ ), 71.01 (CH), 72.75 (CH), 73.25 (CH ₂ ), 74.84 (CH), 77.94 (CH), 99.28 (CH), ); IR v _max : 3388 (OH), 2922, 2853, 1456, 1365, 1192, 1144, 1110, 1045, 899; HRMS (ESI ⁺ ) calcd for C ₅ H ₃ O NA ₆ : 329.1935 [M + Na] ⁺ ; measured: 329.1935 (-0.2 ppm); Rf = 0.38 (EtOAc / EtOH 10: 1). Example 2d

Methyl 6-O-Decyl α-D-glucopyranoside (2d) and methyl 4-O-decyl OC-D-glucopyranoside (2d '): Compounds 2d and 2d' were prepared from 4,6-O -decylidene α-D-glucopyranoside methyl 1d (6.00 g, 18 mmol) according to the general procedure (B). A 77:23 mixture of 2d and 2d (1 .52 g, 25%) was obtained as a white paste. To facilitate the characterization of the compounds, the regioisomers of the mixture can be separated by chromatography on a column of silica gel (EtOAc / cyclohexane, from 50:50 to 100: 0 then EtOH / EtOAc 10:90). 2d: Colorless oil. ¹ H NMR (300 MHz, CDCl ₃ ) δ _Η : 0.86 (3H, t, J = 7, CH ₃ alkyl), 1-1.338 (14H, m, 7 (CH ₂ ) alkyl), 1 .47-1.66 (2H, m, CH ₂ alkyl), 3.40 (3H, s, OCH ₃ ), 3.42-3.89 (8H, m), 4.32 (3H, br s, OH), 4.73 (1H, d, J = 4, CH-anomeric); ¹³ C NMR (75 MHz, CDCl ₃ ): _C : 14.22 (CH ₃ ), 22.79 (CH ₂ ), 26.15 (CH ₂ ), 29.45 (CH ₂ ), 29.65 (CH ₂ ), 29.72 (2CH ₂ ), 29.74; (CH ₂ ), 32.02 (CH ₂ ), 55.27 (OCH ₃ ), 70.41 (CH ₂ ), 70.48 (CH), 71.02 (CH), 72.04 (CH), 72.23 (CH ₂ ), 74.40 (CH) 99.60 (CH); IR v _max : 3400 (OH), 2919, 2852, 1467, 1369, 1123, 1043, 1014, 901; HRMS (ESI ⁺⁾ calculated for Ci ₇ H ₃ 4Na0 _6: 357.2248 [M + Na] ^+; measured: 357.2247

(+0.1 ppm); Rf = 0.30 (EtOAc / EtOH 10: 1). 4d: White solid. ¹ H NMR (300 MHz, CDCl _{3) δ} Η: 0.88 (3H, t, J = 7, CH ₃ alkyl), 1 .10-1 .39 (14H, m, 7 (CH ₂₎ alkyl), 1. 47-1.68 (2H, m, CH ₂ alkyl), 2.13 (4H, br s, OH + H), 3.25 (1H, t, J = 10); 3.41 (3H, s, OCH ₃ ), 3.48 (1H, dd, J = 10 and 4), 3.54-3.68 (2H, m), 3.69-3.94 (3H, m), 4.75 (1H, d, J); = 4, CH-anomeric); ¹³ C NMR (75 MHz, CDCl 3) 5 _C: 14.25 (CH _3), 22.82 (CH _2), 26.21 (CH _2), 29.45 (CH _2), 29.63 (CH _2),

29.70 (CH ₂ ), 29.73 (CH ₂ ), 30.47 (CH ₂ ), 32.02 (CH ₂ ), 55.47 (OCH ₃ ), 62.18 (CH ₂ ), 70.99 (CH), 72.82 (CH), 73.28 (CH ₂₎ ), 75.08 (CH), 77.95 (CH), 99.19 (CH); IR v _max : 3370 (OH), 2923, 2853, 1466, 1370, 1317, 1192, 1112, 1070, 1050, 899; HRMS (ESI ⁺ ) calculated for C ₇ H 43 N ₄ O ₆ : 357.2248 [M + Na] ⁺ ; measured: 357.2252 (-1.2 ppm); Rf = 0.38 (EtOAc / EtOH 10: 1).

Example 2e:

Methyl 6-O-Dodecyl α-D-glucopyranoside (2e) and methyl 4-O-dodecyl α-D-glucopyranoside (2e '): Compounds 2e and 2e' were prepared from 4,6-O methyl dodecylidene α-D-glucopyranoside 1 e (5.00 g, 14 mmol) according to the general procedure (B). 73:27 2nd and 2nd mixture (2.52 g, 51%) was obtained as a white solid. To facilitate the characterization of the compounds, the regioisomers of the mixture can be separated by chromatography on a column of silica gel (EtOAc / cyclohexane, from 50:50 to 100: 0 then EtOH / EtOAc 10:90). 2nd: White solid. ¹ H NMR (300 MHz, CDCl ₃ ) δ _Η : 0.87 (3H, t, J = 7, CH ₃ alkyl), 1 .09-1 .44 (18H, m, 9 (CH ₂ ) alkyl), 1. 47-1.70 (2H, m, CH ₂ alkyl), 3.41 (3H, s, OCH ₃ ), 3.43-3.84 (7H, m), 4.21 (3H, br s, OH), 4.74 (1H, d , J = 4, CH-anomeric); ¹³ C NMR (75 MHz, CDCl ₃ ): _C : 14.25 (CH ₃ ), 22.82 (CH ₂ ), 26.17 (CH ₂ ), 29.50 (CH ₂ ), 29.67 (CH ₂ ), 29.73 (CH ₂ ), 29.77; (CH ₂ ), 29.80 (2CH ₂ ), 29.83 (CH ₂ ), 32.06 (CH ₂ ), 55.35 (OCH ₃ ), 70.33 (CH), 70.51 (CH ₂ ), 71.23 (CH), 72.10 (CH ₂ ), ), 72.30 (CH ₂ ), 74.49 (CH), 99.57 (CH); IR v _max : 3402 (OH), 2918, 2851, 1467, 1370, 1057, 0150, 902; HRMS (ESI ⁺ ) calcd for C38HasNaOe: 385.2561 [M + Na] ⁺ ; measured: 385.2558 (+0.6 ppm); Rf = 0.16 (EtOAc / EtOH 1 0: 1). 2nd ': white solid. ¹ H NMR (300 MHz, CDCl ₃ ) δ _Η : 0.87 (3H, t, J = 7, CH ₃ alkyl), 1 .14-1 .42 (18H, m, 9 (CH ₂ ) alkyl), 1. 47-1.71 (2H, m, CH ₂ alkyl), 2.16 (3H, br s, OH), 3.24 (1H, t, J = 1 O); 3.41 (3H, s, OCH ₃ ), 3.49 (1H, dd, J = = 10 and 4), 3.54-3.66 (2H, m), 3.69-3.91 (4H, m), 4.74 (1H, d, J = 4, CH-anomeric); ¹³ C NMR (75 MHz, CDCl ₃ ): _C : 14.26 (CH ₃ ), 22.83 (CH ₂ ), 26.20 (CH ₂ ), 29.49 (CH ₂ ), 29.64 (CH ₂ ), 29.74 (2CH ₂ ), 29.77; (CH ₂ ), 29.80 (CH ₂ ), 30.47 (CH ₂ ), 32.06 (CH ₂ ), 55.46 (OCH ₃ ), 62.1 (CH ₂ ), 70.99 (CH), 72.81 (CH), 73.28 (CH ₂₎ ), 75.05 (CH), 77.94 (CH), 99.20 (CH); IR v _max : 3295 (OH), 2913, 2848, 1739, 1469, 1370, 1114, 067, 1042, 993; HRMS (ESI ⁺⁾ calculated for Ci ₉ H ₃ 8Na0 _6: 385.2561 [M + Na] ^+; measured: 385.2574 (-3.5 ppm); Rf = 0.24 (EtOAc / EtOH 10: 1). Example 2f:

 2f 2f

Methyl (2f) 6-O-dodecyl α-D-mannopyranoside and methyl 4-O-dodecyl α-D-mannopyranoside (2f): Compounds 2f and 2f were prepared from 4,6-O-dodecylidene methyl α-D-mannopyranoside 1 g (0.70 g, 1.94 mmol) according to the general procedure (B). After reaction, the residue was purified by silica gel column chromatography (EtOAc / cyclohexane, 40:60). A 75:25 inseparable mixture of 2f and 2f (0.24 g, 34%) was obtained as a colorless oil. ¹ H NMR (300 MHz, CDCl ₃ ) δ _Η for the major regioisomer 2f: 0.88 (3H, t, J = 6.7, CH ₃ ), 1 .20-1 .35 (18H, m, 9 CH ₂ ), 1 .55-1 .61 (2H, m, CH _2), 3.35 (3H, s, OCH _3), 3.44-3.57 (2H, m, OCH _2), 3.60- 3.98 (6H, m, CH ² + CH ³ + CH ⁴ + CH ⁵ + CH ₂ ⁶ ), 4.73 (1H, d, J = 1.5, CH ¹ ); ¹³ C NMR (75 MHz, CDCl 3) 5 _C for the majority regioisomer 2f: 14.06 (CH ₃ ), 22.63 (CH ₂ ), 25.95 (CH ₂ ), 29.30 (CH ₂ ), 29.42 (CH ₂ ), 29.44 (CH 3) ₂ ), 29.54 (CH ₂ ), 29.57 (CH ₂ ), 29.58 (CH ₂ ), 29.61 (CH ₂ ), 31.86 (CH ₂ ), 54.96 (OCH ₃ ), 69.50 (CH ⁵ ), 69.65 (CH ² ), ⁴ ), 70.37 (CH ² ), 71.12 (CH ₂ ⁶ ), 71.67 (CH ₃ ), 72.14 (OCH ₂ ), 100.7 (CH ¹ ); IR v _max : 3650, 3238 (OH), 2921, 2852, 2159, 2029, 1976, 1156; HRMS (ESI ⁺ ) calcd for C38HasNaOe: 385.2561 [M + Na] ⁺ ; measured: 385.2555 (+1.5 ppm); Rf = 0.22 (cyclohexane / EtOAc, 60:40).

Example 2g:

Methyl (2g) 6-O-Dodecyl α-D-galactopyranoside and methyl 4-O-dodecyl OC-D-galactopyranoside (2 g '): Compounds 2g and 2g' were prepared from 4,6-O methyl dodecylidene α-D-galactopyranoside 1 h (0.69 g, 1.90 mmol) according to the general procedure (B). After reaction, the residue was purified by silica gel column chromatography (EtOAc / cyclohexane, 50:50). An inseparable 90:10 mixture of

2g and 2g (0.19g, 27%) was obtained as a white solid. Melting point = 110 ° C; ¹ H NMR (300 MHz, CDCl ₃ ) δ _Η for the majority regioisomer 2g: 0.87 (3H, t, J = 6.6, CH ₃ ), 1.24 (18H, br s, 9 CH ₂ ), 1 .55- 1.60 (2H, m, CH ₂ ), 3.41 (3H, s, OCH ₃ ), 3.48 (2H, t, J = 6.7, OCH ₂ ), 3.67-3.90 (5H, m, 3 CH + CH ₂ ). 4.04-4.05 (1H, m, CH), 4.83 (1H, d, J = 3.5, CH ¹ ); ¹³ C NMR (75 MHz, CDCl ₃ ) 5 _C for the majority regioisomer 2g ': 14.24

(CH ₃ ), 22.81 (CH ₂ ), 26.17 (CH ₂ ), 29.47 (CH ₂ ), 29.59 (CH ₂ ), 29.61 (CH ₂ ), 29.70 (CH ₂ ), 29.74 (CH ₂ ), 29.76 (2 CH ₂ ), 29.78 (CH ₂ ), 32.44 (CH ₂ ), 55.59 (OCH ₃ ), 69.68 (CH), 70.47 (CH), 71.1 (CH), 71 34 (CH), 72.30 (CH ₂ ), 99.84 (CH ¹ ); IR v _max : 3651, 3250 (OH), 2917, 2849, 2493, 2430, 2159, 2029, 1976, 1042; HRMS (ESI ⁺ ) calcd for C38HasNaOe: 385.2561 [M + Na] ⁺ ; measured: 385.2548 (+3.2 ppm); Rf = 0.30 (cyclohexane / EtOAc, 40:60). EXAMPLE 3 Synthesis of a Sorbitan Acetal

Dehydration of sorbitol:

 D-sorbitol (20 g, 10 mmol) and 0.1 mol% of camphorsulfonic acid are added to a 150 ml autoclave of stainless steel. The reactor is hermetically sealed, purged three times with hydrogen and then the hydrogen is introduced to a pressure of 50 bar. The system is then heated to 140 ° C and stirred with a mechanical stirrer for 15 hours. After cooling to room temperature, the hydrogen pressure was released and the reaction crude was diluted in ethanol (200 mL) to obtain a yellow homogeneous mixture. The solvent is evaporated under reduced pressure and the residue is then crystallized from cold methanol and filtered under vacuum. The crystalline material was washed with cold methanol to give 1,4-sorbitan (5.88 g, 35% theoretical) as a white solid. The purity is> 98%, as determined by HPLC, while the crystals showed a melting point of 13-1-14 ° C. The degree of conversion of the reaction was determined to be 73%, whereby a mixture of sorbitol, 1,4-sorbitan, isosorbide and some by-products is obtained in a very limited amount, so that the ratio of 1,4-sorbitan: isosorbide was determined to be 80:20.

 Acetalisation of sorbitan in DMF:

In a sealed tube, the 1.4 sorbitan (0.5 g, 3 mmol) was dissolved in DMF (1.4 mL). Valeraldehyde (107 μl, 1 mmol) was added dropwise under argon followed by the addition of camphorsulfonic acid (10 mg, 10% m) before closing the tube. The mixture is heated to 95 ° C with magnetic stirring. After 15 hours, the reaction mixture was cooled and the solvent evaporated under reduced pressure. A degree of conversion of 95% has been achieved. The residue was diluted in ethyl acetate and the excess of 1, 4 sorbitan was filtered and washed with ethyl acetate. The filtrate was concentrated under reduced pressure. The residue was purified by flash chromatography (EtOAc: cyclohexane 80:20 to 100: 0) to give the sorbitan acetal (0.22 g, 89% isolated yield) as a colorless oil. HPLC revealed a mixture of 4 isomers. Trans-acetalization of sorbitan in ethanol:

 In a round-bottomed flask of 1,4-sorbitan (0.5 g, 3 mmol) was dissolved in ethanol (7.5 ml) and 1,1-diethoxypentane (1.15 ml, 6 mmol) dissolved in water. ) was added under a stream of argon, followed by camphorsulfonic acid (50 mg, 10% w / w). The mixture is heated to 80 ° C and with magnetic stirring. After 3 hours, the mixture was neutralized and concentrated under reduced pressure. The residue was purified by flash chromatography (80:20 to 100: 0 ethyl acetate / cyclohexane) to give the sorbitan acetal (0.43 g, 66% isolated yield) as a colorless oil. HPLC revealed a mixture of 4 isomers.

EXAMPLE 4 Synthesis of a Sorbitan Ether "One-Pot" Synthesis of Sorbitan Ethers from 1-A-Sorbitan

In a 100 mL round bottom flask, 1,4-sorbitan (10 g, 62 mmol) is dissolved in dry CPME (30 mL) in the presence of Na ₂ SO ₄ (6.5 g, 50 mmol), under an argon atmosphere. Valdeldehyde (3.3 mL, 31 mmol) was added dropwise, followed by Amberlyst 15 (530 mg, 20% mvaletaldehyde). The mixture is heated to 80 ° C with magnetic stirring. After 3 hours, the hot mixture is filtered, washed with CPME (2 x 25 mL) and the filtrate is concentrated under reduced pressure. Without additional purification, the mixture is diluted in CPME (300 mL), dried over MgSO ₄ and filtered. The filtrate is introduced into a 500 ml stainless steel autoclave, and 5% -Pd / C (3.3 mg) is added. The reactor is well closed, purged three times with hydrogen, before hydrogen is introduced under pressure (30 bar). The system is heated to 120 ° C and stirred for 15 hours. After cooling to room temperature, pressurized hydrogen is released, the reaction mixture is dissolved in absolute ethanol (250 mL) and filtered (Millipore Durapore Filter 0.01 micron). The filtrate is evaporated under reduced pressure and the residue (5.8 g) is purified by flash chromatography (EtOAc / cyclohexane 90:10 to 100: 0, then EtOH / EtOAc 10:90). Thus a mixture of pentyl (1,4) sorbitan ethers (3.97 g, 56%) was obtained as a colorless oil (purity> 98% by RM NMR).

EXAMPLE 5 Measurement of the Bacteriostatic Properties of Acetals and Methyl Glucopyranoside Ethers on Gram-Positive Bacteria The bacteriostatic properties of the derivatives are evaluated by measuring their minimum inhibitory concentration (MIC) with respect to the bacteria tested. Such a measurement is carried out by a microdilution method carried out in a 96-well microplate according to the conditions defined below. The bacteria tested:

 Minimum inhibitory growths (MICs) are performed on Gram-positive bacterial strains according to the recommendations of the Clinical Laboratory Standards Institute, 6th ed., Approved standard M100-S1 7. CLSI, Wayne, PA, 2007).

 The Gram-positive bacteria studied are: L monocytogenes (CIP 103575), E. faecalis (ATCC® 29212 ™) and S. aureus (ATCC® 292213 ™).

 The compounds of interest tested:

 C5, C6, C8, C1 0 and C12 methyl glucopyranoside acetals and ethers (number of carbons in the alkyl chain).

Inoculum preparation:

The cultures studied, freshly isolated (after incubation on a blood agar at 37 ° C. for 18 h), are taken up in sterile water (10 ml) until obtaining a suspension at 0.5 Mac Farland (Me). that is 1 to 2 χ 1 0 ⁸ CFU (bacteria) / cm ³ . The bacterial suspension was then diluted to obtain a final concentration of 5 ^χ 10 ⁵ CFU / cm ³ .

Preparation of multiwell plates for reading the MIC:

Each well contains an identical amount of Mueller-Hinton medium (rich medium allowing the culture of the bacteria) and bacteria of 5 ^χ 10 ⁵ CFU / cm ³ final.

 The compounds of interest to be tested are solubilized in 2.5% of ethanol before being diluted to different concentrations of two in two.

 On the multiwell plate, a first series has been provided comprising the culture medium without the compound of interest to be tested. It corresponds to the growth control (control wells). These controls serve as a reference for comparing bacterial growth with those of subsequent wells comprising different concentrations of the compound of interest to be tested. The second set of wells comprises the stock solution of the compound of interest to be tested at a concentration in the 4 mM well. Each series of wells was diluted two by two until the last set for a final concentration of

0.003 mM. Each concentration is duplicated within the same plate. The plate is incubated for 18 hours at 37 ° C. The reading after incubation shows a disorder in the control wells (revealing a bacterial growth). In case of antibacterial activity, the bacterial growth is inhibited which results in the absence of appearance of disorder or bacterial pellet. Inhibition of this bacterial growth by the tested compound may correspond to either a bacteriostatic activity of the molecule (inhibits growth bacterial) or bactericidal activity of the molecule (causes death of the bacterium).

Bacterial enumeration:

 In order to determine whether the tested agents are bactericidal, the minimum bactericidal concentration (CMB) is determined. The CMB corresponds to the concentration leaving a number of bacterial survivors <4 Log. For this, a bacterial count is made from clear wells or without bacterial pellet (C≤CMI). To do this, a dilution was made with the two wells of the same concentration before

 100 ^

seeding on a blood agar using the Spiral technique. After incubation for 24 h at 37 ° C, the visual count was used to determine the minimum concentration from which no further bacterial growth occurs.

Tests on acetal derivatives and methyl glucopyranoside ethers

 The tests were performed on Gram-positive bacteria with methyl glucopyranoside derivatives. The test compound solutions are diluted in ethanol to a solvent concentration that does not act on bacterial growth (2.5% m). The solutions after sterilization are diluted in water. However, C10 and C1 2 methyl glucopyranoside acetals have low solubility in water. Due to the formation of precipitates in the solutions, the effect of these methyl glucopyranoside acetals at 010 and C1 2 could not be evaluated. The results of the antimicrobial tests obtained on the three bacterial strains L monocytogenes (CIP 103575), E. faecalis (ATCC® 2921 2 ™) and S. aureus (ATCC® 292213 ™) are summarized in Table 1.

The results below (Table 1) reveal that methyl glucopyranoside derivatives having a hydrophobic chain of less than 8 carbons (Inputs 1 and 2) have a minimum inhibitory concentration greater than 4mM. In other words, these compounds have no inhibitory effect on the growth of gram-positive bacteria. Inhibition of bacterial growth is observed from compounds having aliphatic chains greater than or equal to 8 carbons. Indeed, this is indicated by the absence of turbidity of the then corresponding to the octylidene of methyl glucopyranoside and the mixtures of ethers (4-O-alkyl and 6-O-alkyl) in 08 and 010 (entries 3 and 4). These compounds have a MIC between 0, 12 and 4 mM and more precisely between 2 and 4 mM. Methyl dodecyl glucopyranoside (entry 5) shows the best results. Indeed, a MIC less than 0.1 mM and more precisely between 0.1 2 and 0.03 mM depending on the bacterial strains studied is measured.

Table 1. Antimicrobial Results for Methyl Glucopyranoside Derivatives on Gram-positive: Minimal Inhibitory Concentration (MIC) in mmol / L EXAMPLE 6 Measurement of the Bacteriostatic Properties of Acetals and Sorbitan Ethers Derivatives on Gram-Positive Bacteria

The C5, C6, C8, C10 and C12 sorbitan acetals and ethers were then tested under the same conditions as above and on the same bacterial strains (see Example 5). The results obtained are summarized in Table 2.

Gram positive: Minimum Inhibitory Concentration (MIC) in mmol / L Based on the observation of 96-well microplates, sorbitan ethers and acetals with aliphatic chains less than or equal to 10 carbons do not exhibit antimicrobial properties because all wells contain a bacterial disorder or pellet. The only bacterial inhibition is observed for compounds derived from dodecyl (entry 5).

 In fact, with concentrations of less than 12 mM, the acetal and the C1 2 ether of sorbitan inhibit the bacterial strains studied. Note that the inventors were able to obtain more soluble C12 compounds for analysis of their bacteriostatic properties compared to the preceding methyl glucopyranoside compounds and more particularly the methyl glucopyranoside 4,6-O-dodecylidene.

EXAMPLE 7: Bactericidal property of acetal derivatives or ethers of sorbitan or of methyl glucopyranoside on Gram-positive bacteria

In order to determine the bactericidal effect of the compounds having bacteriostatic properties, the no-disturbed wells of Examples 5 and 6 were reseeded on agar. The results obtained after incubation overnight are shown in Table 3.

Table 3. Antimicrobial Results for Methyl Glucopyranoside Derivatives and Gram-Positive Sorbitan Derivatives: Minimal Inhibitory Concentration (MIC) in mmol / L, Minimal Bactericidal Concentration (CMB) in mmol / L (in italics)

These results show that the compounds having a C8 group have no bactericidal effect since below 2 to 4 mM, clones are observed on agar after reseeding. Methyl glucopyranoside (EthCI OMeGlu) has a CMB of 0.5 mM against L monocytogenes and E. faecalis (Inputs 1 and 3). Nevertheless, for S. aureus which is a more virulent strain, the CMB amounts to 2 mM (entry 2). The strongest bactericidal effect is observed for methyl glucopyranoside C12 ethers (EthC12MeGlu). Indeed, a CMB of 0.12 mM (entry 2) is measured for S. aureus and 0.03 mM (entries 1 and 3) with respect to L monocytogenes and E. faecalis.

 As regards the sorbitan derivatives, only the compounds containing 12-carbon chains and exhibiting bacterial inhibition were analyzed and compared with products of the same chain length but on methyl glucopyranoside. Sorbitan dodecylidene acetal has been shown to be a bactericidal compound of the L monocytogenes and E. faecalis strains. 0.03 mM and bacteriostatic S. aureus at 0.12 mM. In order to confirm that the measured properties of the acetals are those of the amphiphilic compound and not of its hydrolysis products, the properties of dodecanal have been tested on the different bacterial strains and no antimicrobial activity has been observed at lower concentrations or equal to 4 mM. Thus, the C12 acetal of sorbitan is active as such and this activity does not come from the corresponding aldehyde.

 While the mixture of dodecyl sorbitan ethers has a CMB of 0.12 mM for all Gram positive strains tested. With MICs of 0.03 mM, sorbitan acetals are as effective as methyl chain glucopyranoside ethers of the same chain length against L monocytogenes and E. faecalis. (entries 1 and 3).

 However, the mixture of C12 sorbitan ethers is on the same scale as the methyl glucopyranoside EthC12s for S. aureus (entry 2). In addition, the C12 sorbitan acetals show results identical to those of methyl glucopyranoside EthC12 for all the strains tested. It can therefore be concluded that the C12 sorbitan acetals and ethers, even in the form of a mixture of regioisomers and diastereoisomers, have very interesting antimicrobial and bactericidal properties.

 These results show that the sorbitan derivatives can present a new range of highly active bacteriostatic and bactericidal products. EXAMPLE 8 Evaluation of Surfactant and Antimicrobial Properties

During the study of the physicochemical and antimicrobial properties, all the synthesized products could be tested. These analyzes highlight the different profiles of amphiphilic compounds: hydrotropes and surfactants, as well as the values of the Minimum Inhibitory Concentrations (MIC) of each compound on Gram-positive bacteria. The best surfactant and antimicrobial results are compared in Table 4.

Table 9. Comparative Results Between Critical Micellar Concentrations (CMC) and Minimum Inhibitory Concentrations (MIC) in (mmol / L) on the Products of Interest: Minimum Inhibitory Concentration (MIC) in mmol / L

From the above results, it is found that the C12 derivatives of methyl glucopyranoside and sorbitan have the best results for both their surfactant and antimicrobial properties (on Gram positive) because they have the lowest CMC and CMI. For methyl dodecyl glucopyranoside and dodecylidene sorbitan (inputs 1 and 2), the CMC value is in the range of MIC. The dodecyl-sorbitan ether has a slightly lower CMC (0.09 mM) than its MIC (0.12 mM), but these concentrations are still relatively close (entry 3).

EXAMPLE 9 Comparative Tests with Compounds Known from the Prior Art

The activity of the sorbitan or methyl glucopyranoside derivatives has been compared with that of compounds of similar structures or of a commercial compound such as monolaurin (ML) in the table below.

Table 5. Comparative Results Between Reference Products and Methyl Glucopyranoside and Sorbitan Ethers: Minimal Inhibitory Concentration (MIC) in mmol / L

The results obtained demonstrate that the derivatives according to the invention are just as effective as monolaurin (ML) since the difference in MIC obtained between the mixtures of sugar C12 ethers (EthC12MeGlu and EthC12Sorb) and monolaurin is

10 weak. In addition, the presence as a mixture of regioisomers of the ethers does not affect the antimicrobial properties in view of the results between the pure 6-0-EthC12MeGlu (MIC of 0.04 mM on L. monocytogenes) and the mixture (4+ 6) -O-EthC12MeGlu (MIC of 0.03 mM on L. monocytogenes). This clearly indicates that each of the isomers of the mixture can be active to varying degrees on different bacterial strains. In

If 4-0-EthC12MeGlu were completely inactive, the observed MIC of the (4 + 6) -O-EthC12MeGlu mixture would necessarily be greater than 0.04 nM.

 The connective function between the lipophilic and hydrophilic part also affects the MIC values. Thus, in the case of the methyl dodecyl glucopyranoside derivatives, the MICs are slightly lower for the ethers compared with the corresponding ester.

(0.03-0.12 mM for EthC12MeGlu and 0.08-0.31 mM for EstC12MeGlu). However, since the stability of the ether functions in a biological medium is higher than the esters (sensitive to esterases), the compounds comprising an ether function will therefore have a prolonged activity which makes these derivatives particularly advantageous compounds.

EXAMPLE 10 Measurement of the Bacteriostatic Properties of C12 Monosaccharide Acetals and C12 Monosaccharide Derivatives on Gram-Positive Bacteria The best results having been observed with compounds having a C1 2 alkyl group, tests were carried out on a larger panel of Gram-positive strains with compounds obtained according to Examples 1 and 2.

The compounds of interest tested:

 Methyl glucopyranoside acetals

 • Methyl 4,6-O-Dodecylidene α-D-glucopyranoside (1 e)

 Methyl 4,6-O-Dodecylidene β-D-glucopyranoside (1 f)

 Mixture of methyl glycopyranoside ethers

 Methyl 6-O-Dodecyl α-D-glucopyranoside (2e) and methyl 4-O-dodecyl-D-glucopyranoside (2e ')

 Methyl 6-O-Dodecyl α-D-mannopyranoside (2f) and methyl 4-O-dodecyl-D-mannopyranoside (2f)

 Methyl 6-O-Dodecyl α-D-galactopyranoside (2 g) and methyl 4-O-dodecyl-D-galactopyranoside (2 g)

 Mixture of sorbitan ethers

 3-0-Dodecyl-1,4-D-sorbitan, 5-O-dodecyl-1,4-D-sorbitan and 6-O-dodecyl-1,4-D-sorbitan

- Preparation of the inoculum:

The cultures studied, freshly isolated (after incubation on a blood agar at 37 ° C. for 18 h), are taken up in sterile water (10 ml) until obtaining a suspension at 0.5 Mac Farland (Me). at 1 to 2 ^χ 1 0 ⁸ CFU (bacteria) / cm ³ . The bacterial suspension was then diluted in order to obtain a final concentration of 1 ^× 10 ⁶ CFU / cm ³ .

 - Preparation of multiwell plates for reading the MIC:

Each well contains an identical amount of Mueller-Hinton medium (rich medium allowing the culture of bacteria) and bacteria of 0.5 ^χ 1 0 ⁶ CFU / cm ³ final. The compounds of interest to be tested are solubilized in ethanol or DMSO at 25 mg / ml before being diluted to different concentrations of two in two. On the multi-well plate, a first series has been provided comprising the culture medium without the compound of interest to be tested. It corresponds to the growth control (control wells). These controls serve as a reference for comparing bacterial growth with those of subsequent wells comprising different concentrations of the compound of interest to be tested. The second set of wells comprises the stock solution of the compound of interest to be tested at a concentration in the well of 256 mg / L (7 mM). Each series of wells was diluted two-fold to the last set for a final concentration of 0.25 mg / L (0.0007 mM). Each concentration is duplicated within the same plate. The plate is incubated for 18 hours at 37 ° C. The reading after incubation shows a disorder in the control wells (revealing a bacterial growth). In case of antibacterial activity, the bacterial growth is inhibited which results in the absence of appearance of disorder or bacterial pellet.

 Minimum inhibitory growth (MIC) is performed on Gram-positive bacterial strains according to the recommendations of the Clinical Laboratory Standards Institute, 6th ed, Approved standard M100-S17 CLSI, Wayne, PA, 2007 ). The clinical strains were isolated at the Lyon hospital.

 The gram-positive bacteria studied are as follows:

- Staphylococci S. aureus; ATCC ^® ™ 29213, ATCC 25923,

 Staphylococci S. aureus strains resistant to methicillin (Lac-Deleo USA 300), (MU 3), (HT 2004-0012), LY 199-0053, (HT 2002-0417), (HT 2006-1004),

Staphylococcal S. aureus strains resistant to daptomycin (ST 2015-0188) (ST 2014 1288), (ST 2015-0989).

- Enterococci E. faecalis (ATCC ^® 29212 ™), clinical strains of enterococci

E. faecalis isolated from urine: the strain 015206179901 (hereinafter 9901), the strain 015205261801 (hereinafter 1801)

 - Enterococci: E. faecium (CIP 103510), clinical strains c / Enterococci E. faecium: Van A 0151850763 (hereinafter Van A); the strain 015 205731401 (hereinafter 1401),

- Listeria: L monocytogenes (CIP 103575), isolated clinical strain of blood culture (015189074801, LM1), isolated strain of cerebrospinal fluid (015170199001, LM2), isolated clinical strain of blood culture (015181840701, LM3). Preparation of the inoculum:

The cultures studied, freshly isolated (after incubation on a blood agar at 37 ° C. for 18 h), are taken up in sterile water (10 ml) until a suspension of 0.5 Mac Farland (Me) is obtained. at 10 ⁸ CFU (bacteria) / cm ³ . The bacterial suspension was then diluted in order to obtain a final concentration of 10 ⁶ CFU / cm ³

- Results for strains of the genus Staphylococcus

 Table 6. Antimicrobial results for methyl glycopyranoside ethers and acetals derivatives as well as sorbitan on different strains of Staphylococcus aureus: Minimal Inhibitory Concentration (MIC) in mg / L

According to the observation of the 96-well microplates, all the acetal or ether derivatives of monosaccharides are active against the strains of staphylococci tested (8 <CMI < 64 mg / L) except for galactose ether (C12-Eth-a-MeGalac) and acetal for glucose (C12-Ac-a-MeGlu) (MIC> 256 mg / L).

 - Results for Enterococcus genus strains

 Table 7. Antimicrobial results for sugar ethers derivatives and sugar and sorbitan acetals on various enterococcal strains. Minimal Inhibitory Concentration (MIC) in mg / L

Good antibacterial activity observed for all the enterococci strains 32 <MIC <8 mg / L for all the molecules tested except the acetal has glucose (C12-Ac-a-MeGlu). - Results for strains of the genus Listeria

 Table 8. Antimicrobial results for sugar ethers derivatives and sugar and sorbitan acetals on different strains of Listeria Minimal Inhibitory Concentration (MIC) in mg / L.

 Good antibacterial activity observed on all strains of Listeria 64 <

MIC <8 mg / L for all tested molecules.

Claims

A bactericidal or bacteriostatic composition comprising a mixture of positional isomers of monoethers or monoacetals of monosaccharide alkyl or monosaccharide derivative, said monosaccharide derivative being a glycosylated and / or hydrogenated and / or dehydrated monosaccharide, said mixture of isomers of monoethers or monoacetals of monosaccharide or monosaccharide derivative being obtained by a process comprising the following steps:

 a) an acetalization or trans-acetalization of a monosaccharide or a monosaccharide derivative with an aliphatic aldehyde containing from 1 to 18 carbon atoms or the acetal thereof, b) optionally, catalytic hydrogenolysis of the monosaccharide alkyl acetal or the monosaccharide derivative obtained in a) preferentially, without an acid catalyst, and

 c) recovering a mixture of positional isomers of monosaccharide alkyl monoethers or the monosaccharide derivative obtained in b) in which the alkyl group (R) comprises between 1 1 to 18 carbon atoms

 or

 recovering a mixture of positional isomers of monosaccharide alkyl monoacetals or of a monosaccharide derivative obtained in a) in which the alkyl group (R) comprises from 1 to 18 carbon atoms.

A bactericidal or bacteriostatic composition comprising a mixture of positional isomers of monoethers or monoacetals of monosaccharide alkyl or monosaccharide derivative, having an alkyl ether or alkyl acetal radical in two distinct positions of the monosaccharide or of the monosaccharide derivative as well as the pharmaceutically acceptable salts thereof wherein the alkyl group comprises from 1 to 18 carbon atoms, said monosaccharide derivative being a glycosylated and / or hydrogenated and / or dehydrated monosaccharide, preferentially the alkyl group comprises from 1 to 13 atoms of carbon.

3. Composition according to either of claims 1 and 2 characterized in that the monosaccharide is a C6 monosaccharide or their alkyl glycoside, preferably, the monosaccharide is:

 a hexose selected from the group consisting of glucose, mannose, galactose, allose, altrose, gulose, idose and talose

 a hexitane chosen from 1,4-anhydro-D-sorbitol (1,4-arlitan or sorbitan);

 1,5-anhydro-D-sorbitol (polygalitol); 3,6-anhydro-D-sorbitol (3,6-sorbitan); 1, 4 (3,6) -anhydro-D-mannitol (mannitan); 1,5-anhydro-D-mannitol (styracitol); 3,6-anhydro-D-galactitol; 1,5-anhydro-D-galactitol; 1,5-anhydro-D-talitol and 2,5-anhydro-L-iditol or

 a hexitol chosen from mannitol, sorbitol, galactitol and volemitol.

4. Composition according to any one of claims 1 to 3, characterized in that the monosaccharide is a sorbitan and said alkyl acetal radical is in position 3,5-0- or 5,6-0- or said alkyl monoether radical. is in position 3-0-, 5- O- 0U 6-O-.

 5. Composition according to any one of claims 1 to 3, characterized in that the monosaccharide is a glucoside and said alkyl monoacetal radical is in position 4,6-0- or said alkyl monoether radical is in position 4-0- or 6-0.

6. Composition according to any one of claims 1 to 5, characterized in that it is bactericidal or bacteriostatic vis-à-vis Gram-positive bacteria.

7. The composition as claimed in claim 6, characterized in that the Gram-positive bacteria are bacteria of the Branching of Firmicutes, typically of the Bacilli class, chosen in particular from bacteria of the order Lactobacillales or Bacillales.

8. Composition according to either of Claims 6 and 7, characterized in that the Gram-positive bacteria are bacteria of the order Bacillales chosen from the family of Alicyclobacillaceae, Bacillaceae, Caryophanaceae, Listeriaceae, Paenibacillaceae, Pasteuriaceae. , Planococcaceae, Sporolactobacillaceae, Staphylococcaceae, Thermoactinomycetacea and Turicibacteraceae.

9. Composition according to claim 8, characterized in that the Gram-positive bacteria are bacteria of the family Listeriaceae such as a bacterium of the genus Brochothrix or Listeria typically, chosen from L fleischmannii, L grayi, L. innocua, L. ivanovii, L. marthii, L. monocytogenes, L. rocourtiae, L. seeligeri, L. weihenstephanensis and L. welshimeri.

10. Composition according to claim 8, characterized in that the Gram-positive bacteria are bacteria of the family Staphylococcaceae chosen from bacteria of the genus Staphylococcus, Gemella, Jeotgalicoccus, Macrococcus, Salinicoccus and Nosocomiicoccus.

1 1. Composition according to Claim 10, characterized in that the bacteria

Gram positive are bacteria of the genus Staphylococcus selected from S. arlettae, S. agnetis, S. aureus, S. auricularis, S. capitis, S. caprae, S. carnosus, S. caseolyticus, S. chromogenes, S. cohnii , S. condimenti, S. delphini, S. devriesei, S. epidermidis, S. equorum, S. felis, S. florettii, S. gallinarum, S. haemolyticus, S. hominis, S. hyicus, S. intermedius, S. kloosii, S. leei, S. lentus, S. lugdunensis, S. lutrae, S. massiliensis, S. microti, S. muscae, S. nepalensis, S. pasteuri, S. pettenkoferi, S. piscifermentans, S. pseudintermedius , S. pseudolugdunensis, S. pulvereri, S. rostri, S. saccharolyticus, S. saprophyticus, S. schleiferi, S. sciuri, S. simiae, S. simulans, S. stepanovicii, S. succinus, S. vitulinus, S. warneri and S. xylosus.

 12. Composition according to either of Claims 6 and 7, characterized in that the Gram-positive bacteria are Lactobacillales chosen from a family of Aerococcaceae, Carnobacteriaceae, Enterococcaceae, Lactobacillaceae, Leuconostocaceae and Streptococcaceae.

13. Composition according to claim 12 characterized in that the bacteria to

Gram positive are bacteria of the family Enterococcaceae selected from bacteria of the genus Bavariicoccus, Catellicoccus, Enterococcus, Melissococcus, Pilibacter, Tetragenococcus, Vagococcus.

 14. Composition according to either of Claims 12 and 13, characterized in that the Gram-positive bacteria are bacteria of the genus Enterococcus selected from E. malodoratus, E. avium, E. durans, E. faecalis, E. faecium, E. gallinarum, E. hirae, E. solitarius, preferentially E. avium, E. durans, E. faecalis and E. faecium.

 15. Composition according to any one of claims 1 to 14 characterized in that it is incorporated into a food composition, cosmetic, pharmaceutical, phytosanitary, veterinary or surface treatment.

 16. Composition according to any one of claims 1 to 14, for use as a hygiene or dermatological product for external use.

17. A composition as defined in any one of claims 1 to 14 for use in the treatment or prevention of bacterial infections by Gram-positive bacteria.

18. The composition of claim 17 wherein the infection with Gram-positive bacteria is an infection of the skin or mucous membranes, preferably an infection selected from folliculitis, abscess, paronychia, furuncle, impetigo, interdigital infections, anthrax (staphylococcal anthrax), cellulitis, superinfection of wounds, otitis sinusitis, hydradenitis, infectious mastitis, post-traumatic skin infection and burned skin infection.

 19. A method of disinfecting or preventing bacterial colonization by Gram-positive bacteria of a substrate comprising contacting the substrate with a composition according to any one of claims 1 to 14.