Three 1-thio-beta-D-glucopyranosides from the seeds of Afrostyrax lepidophyllus Mildbr.

Three new 1-thioglycosides namely methylthiomethyl 1-thio-beta-D-glucopyranoside (Afrostyraxthioside A), methylsulfonylmethyl 1-thio-beta-D-glucopyranoside (Afrostyraxthioside B) and methylsulfonylmethylthiomethyl 1-thio-beta-D-glucopyranoside (Afrostyraxthioside C) were isolated from the seeds of Afrostyrax lepidophyllus Mildbr. Their structures were mainly elucidated by using one- and two-dimensional NMR and mass spectroscopies and also by an efficient one-step synthesis. Moreover, Afrostyraxthiosides A, B and C constitute a new subclass of 1-thioglycosides isolated from natural sources.