Shuang WANG, Ling ZHANG, Liang-Yan LIU, Ze-Jun DONG, Zheng-Hui LI, Ji-Kai LIU
Investigation of the culture of basidiomycete Polyporus ellisii led to the isolation of a novel compound 3β, 9α, 15α-trihydroxy-(22E, 24R)-10(5→4)-abeo-ergosta-6, 8(14), 22-trien-5-one(1) with a new 5/7/6/5 ring system of ergosterol skeleton. In addition, five new steroids, 5β, 6β-epoxy-3β, 7α, 9α-trihydroxy-(22E, 24R)-ergosta-8(14), 22-dien-15-one(2), 5β, 6β-epoxy-3β, 7α-dihydroxy-(22E, 24R)-ergosta-8(14), 22-dien-15-one(3), 5α, 6α-epoxy-3β, 9α, 15α-trihydroxy-(22E, 24R)-ergosta-8(14), 22-dien-7-one(4), 15α-acetoxy-(22E, 24R)-ergosta-4, 6, 8(14), 22-tetraen-3-one(5), 15β-methoxy-(22E, 24R)-ergosta-4, 6, 8(14), 22-tetraen-3-one(6), along with four known ergosterols(7-10), were obtained. All structures were elucidated based on 1D and 2D NMR spectral data. New compounds were evaluated for cytotoxicity against five human cancer cell lines, only compound 4 was found to exhibit a favorable cytotoxicity profile toward all tested tumor cell lines.