Influence of intramolecular hydrogen bonds on regioselectivity of glycosylation. Synthesis of lupane-type saponins bearing the OSW-1 saponin disaccharide unit and its isomers. (24th March 2016) - Kuczynska, Kinga
Highlights: Lupane-type saponins bearing OSW-1 disaccharide and its stereoisomers were prepared. Influence of hydrogen bond network on regioselectivity of glycosylation was studied. Inversion of the arabinopyranoside rings was observed. Cytotoxic activity of lupane-type saponins was evaluated in vitro. Graphical abstract: Abstract: A series of lupane-type saponins bearing OSW-1 disaccharide unit as well as its regio- and stereoisomers were prepared and used for the structure–activity relationships (SAR) study. Unexpected preference for 1→4-linked regioisomers and an unusual inversion of the conformation of the sugar rings were noted. Cytotoxic activity of new lupane compounds was evaluated in vitro and revealed that some saponins exhibited an interesting bioactivity profile against human cancer cell lines. Influence of the protecting groups on the cytotoxicity was investigated. These results open the way to the synthesis of various lupane-type triterpene and saponin derivatives as potential anticancer compounds.