Antitumor sterols from the mycelia of Cordyceps sinensis
作者:Jin Woo Bok、Leonard Lermer、Jeff Chilton、Hans G Klingeman、G.H.Neil Towers
DOI:10.1016/s0031-9422(99)00128-4
日期:1999.8
Activity guided fractionations led to the isolation of two antitumor compounds 5 alpha,8 alpha-epidioxy-24(R)-methylcholesta-6,22-dien-3 beta-D-glucopyranoside and 5,6-epoxy-24(R)-methylcholesta-7,22-dien-3 beta-ol from the methanol extract of Cordyceps sinensis. Two previously known compounds, ergosteryl-3-O-beta-D-glucopyranoside and 22-dihydroergosteryl-3-O-beta-D-glucopyranoside were also isolated. The structures of hitherto unknown sterols were established by 1D and 2D NMR spectroscopic techniques with the former synthesized in order to confirm the identity of the sugar moiety by chemical correlation. The glycosylated form of ergosterol peroxide was found to be a greater inhibitor to the proliferation of K562, Jurkat, WM-1341, HL-60 and RPMI-8226 tumor cell lines by 10 to 40% at 10 mu g/ml than its previously identified aglycone, 5 alpha,8 alpha-epidioxy-24(R)-methylcholesta-6,22-dien-3 beta-ol. (C) 1999 Elsevier Science Ltd. All rights reserved.
Clayton et al., Journal of the Chemical Society, 1953, p. 2015,2018
作者:Clayton et al.
DOI:——
日期:——
Biogenesis‐Guided Synthesis and Structural Revision of Sarocladione Enabled by Ruthenium‐Catalyzed Endoperoxide Fragmentation
作者:Yuhan Ning、Hailong Tian、Jinghan Gui
DOI:10.1002/anie.202101451
日期:2021.5.10
Sarocladione is the first 5,10:8,9‐diseco‐steroid with a 14‐membered macrocyclic diketone framework to have been isolated from a natural source. Herein we report a biomimetic synthesis of sarocladione in only two or seven steps from inexpensive, commercially available ergosterol. The key feature of this synthesis was a novel ruthenium‐catalyzed endoperoxide fragmentation, which transformed various