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-yl-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.