New α-glucosidase inhibitors from marine algae-derived Streptomyces sp. OUCMDZ-3434

摘要

Wailupemycins H ( 1 ) and I ( 2 ) with a new skeleton coupled two 6-(2-phenylnaphthalene-1-yl)pyrane-2-one nuclei to a –CH₂– linkage were identified from the culture of Streptomyces sp. OUCMDZ-3434 associated with the marine algae, Enteromorpha prolifera . Compounds 1 and 2 are two new α-glucosidase inhibitors with the K_i/IC₅₀ values of 16.8/19.7 and 6.0/8.3 μ M, respectively. In addition, the absolute configurations of wailupemycins D ( 3 ) and E ( 4 ) are also resolved in this paper for the first time.