Novel α-glucosidase inhibitors, CKD-711 and CKD-711a produced by Streptomyces sp. CK-4416 III : physico-chemical properties and structure elucidation

Abstract

We have isolated two novel α-glucosidase inhibitors, O-[4-deoxy-4-(2,3-epoxy-3-hydroxymethyl-4,5,6-trihydroxycyclohexane- 1-y1-amino)-α-D-glucopyranosyl]- (1→4)-O-α-D-glucopyranosyl- (1→4)-α-D-glucopyranose (named CKD-711) and its hexameric analog CKD-711a, from the fermentation broth of Streptomyces sp. CK-4416. HRFAB-MS and NMR analyses reveal that molecular formulae of CKD-711 and CKD-711a are C25H43NO20 and C37H63NO30, respectively with the latter containing two more glucose moieties than the former. Detailed chemical structures of both compounds have been characterized by high-resolution two-dimensional NMR methods.