Efficient regioselective chemical modifications of maltotriose: an easy access to oligosaccharidic scaffold.

Regioselective chlorination of fully unprotected maltotriose has given in high yield 1(I),2(I-III),3(I-III),4(III)-octa-O-acetyl-6(I-III)-trichloro-6(I-III)-trideoxymaltotriose. Moreover, regioselective ditritylation of methyl β-maltotrioside has provided the two regioselectively C(6)-disubstituted trisaccharides. Selective deprotection of these new compounds gives the corresponding diol and halogenated analogues, respectively, in good yield. All compounds have been completely characterized and the substitution pattern in the oligosaccharidic sequence has been elucidated. A new family of amphiphilic carbohydrates, namely the 6-deoxy-6-alkylthiomaltotriose derivatives, bearing either two or three thioalkyl hydrophobic chains, respectively, has been synthesized. Critical micellar concentration (CMC) values as well as the antimicrobial properties have been evaluated for amphiphilic compounds.