Abstract: A process for enzymatically converting a furanoside substrate in a product of interest, includes contacting the substrate with an enzyme in presence of an alcohol acceptor, wherein the enzyme is preferably Araf51, and wherein the product is preferably an alkyl furanoside. The mutant Araf51 enzyme showing improved transglycosylation activity in comparison with the native wild-type (wt) Araf51 enzyme, and a method for screening the mutants are also described.

Abstract: The present invention relates to the use of at least one compound of formula (I) or (II), in which R1 is H and n is an integer from 2 to 10, for the preparation of a medicament for treating diseases chosen from the group comprising tumour, cancer, viral disease, bacterial disease, fungal disease, disease of the immune system, auto-immune disease or disease linked to a deficiency in immunostimulation, in human beings and warm-blooded animals. The invention also relates to new products having a mannose or mannitol termination as well as a method for preparing them.

Abstract: The present invention relates to the use of at least one compound of formula (I) or (II), in which R1 is H and n is an integer from 2 to 10, for the preparation of a medicament for treating diseases chosen from the group comprising tumour, cancer, viral disease, bacterial disease, fungal disease, disease of the immune system, auto-immune disease or disease linked to a deficiency in immunostimulation, in human beings and warm-blooded animals. The invention also relates to new products having a mannose or mannitol termination as well as a method for preparing them.

Abstract: The present invention relates to a novel method of chemically preparing functionalized derivatives of ?-(1,3)-glucans, enabling obtaining oligosaccharides which are free or which comprise specific groups such as, for example, sulphate, phosphate, methyl, in pre-defined positions. This method includes a reaction between a glycosyl donor of formula (Ia) or (Ib) and a glycosyl acceptor of formula (II), defined in the claims. Application: Preparation of biologically active compounds which can be used in the agricultural, cosmetic or pharmaceutical fields.

Abstract: The invention concerns a method for preparing Laminaribiose comprising a step for glycoside binding between a donor and an acceptor of glycosyl. The invention is characterized in that the glycosyl donor is in pyranose form and corresponds to formula (II); the glycosyl acceptor is in furanose form and corresponds to formula (III); said binding step is performed in solution in an anhydrous organic solvent, at a temperature ranging between −80° C. and 40° C., for a time interval ranging between 1 minute and 8 hours, in the presence of a suitable promoter.

Abstract: The invention concerns a novel method for preparing by chemical process functionalised &bgr;-(1,3)-glucan derivatives, enabling to obtain free oligosaccharides or comprising specific groups such as, for instance, sulphate, phosphate, methyl, in predetermined positions. Said method consists in reacting a glycosyl donor of formula (Ia) or (Ib) with a glycosyl scavenger of formula (II), as defined in the claims. The invention is useful for preparing biologically active principles for use in the agricultural, cosmetic or pharmaceutical field.