16653-52-4Relevant articles and documents
A practical synthesis of cephalostatin 1
Shi, Yong,Jia, Lanqi,Xiao, Qing,Lan, Quan,Tang, Xiaohu,Wang, Dahai,Li, Min,Ji, Yu,Zhou, Tao,Tian, Weisheng
supporting information; experimental part, p. 786 - 790 (2011/10/09)
Let's get practical: A new practical synthetic strategy for natural sterols starting from pregnan-(16S,20S)-diols and steroid-(16S),22-lactones is presented. A tandem double oxymercuration-demercuration and a substitution-ketalization cascade are consider
Synthesis and biological activity of unsymmetrical bis-steroidal pyrazines related to the cytotoxic marine natural product cephalostatin 1
Heathcock,Smith
, p. 6828 - 6839 (2007/10/02)
A mild, high-yielding synthesis of symmetrical steroidal pyrazines was achieved from the dimerization of 2-amino-3-ketosteroids, which were produced in situ from the triphenylphosphine-water reduction of the corresponding α-azido ketone. 2-Azidocholestan-3-one gave the dimeric steroidal pyrrazine very cleanly, and two known dimeric pyrazines based on androstanone were also made using this methodology. Both C2-symmetric geometric isomers of the dimeric steroidal pyrrazine derived from cholestane were prepared by reaction of 2,3-diaminocholestane with cholestane-2,3-dione. A route to unsymmetrical bis-steroidal pyrazines was based on the observation that α-acetoxy ketones react with α-amino oximes directly with no need for oxidation of intermediate dihydropyrazines. Heating either 2β,17β-dihydroxyandrostan-3-one diacetate or 2β,17β-dihydroxyhecogenin-3-one diacetate with 2-amino-3-methoxyiminocholestane in toluene at 145°C gave the corresponding unsymmetrical pyrazine in moderate yield. Five of the steroidal pyrazines were evaluated in the National Cancer Institute's new in vitro, disease-oriented antitumor screen, but none showed sufficient activity to warrant in vivo investigation.
Diosgenin, chlorogenin and isochiapagenin from Solanum bahamense L.
Coll,Adam,Padron,et al.
, p. 225 - 226 (2007/10/02)
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