Highly efficient epoxidation of unsaturated steroids using magnesium bis(monoperoxyphthalate) hexahydrate
作者:João F.S. Carvalho、M. Manuel Cruz Silva、M. Luisa Sá e Melo
DOI:10.1016/j.tet.2009.01.100
日期:2009.4
Fast generation of epoxides from the corresponding homoallylic and allylic steroidal olefins was developed by using magnesium bis(monoperoxyphthalate) hexahydrate (MMPP) as oxidant suspended in acetonitrile (CH3CN) at reflux temperature. The protocol involves the use of a safe readily available oxidant along with an easy work-up, which renders the process very efficient. Selective 4,5- and 5,6-epoxidations
Efficient Chemoenzymatic Synthesis, Cytotoxic Evaluation, and SAR of Epoxysterols
作者:João F. S. Carvalho、M. Manuel Cruz Silva、João N. Moreira、Sérgio Simões、M. Luisa Sá e Melo
DOI:10.1021/jm9003973
日期:2009.7.9
A library of diastereomerically pure epoxysterols, prepared by combining chemical and enzymatic methodologies, was evaluated for cytotoxicity toward human cancer and noncancer cell lines. Unsaturated steroids were oxidized by magnesium bis(monoperoxyphthal ate) hexahydrate in acetonitrile, and the resulting epimeric epoxides were enzymatically separated using Novozym 435 or lipase AY. Some of the synthesized epoxysterols have potent cytotoxicity and higher activity on cancer cell lines HT29 and LAMA-84.
Isolation and structure elucidation of seven new polyhydroxylated sulfated sterols from the ophiuroid Ophiolepis superba
Holland, Herbert L.; Jahangir, Canadian Journal of Chemistry, 1983, vol. 61, p. 2165 - 2170
作者:Holland, Herbert L.、Jahangir
DOI:——
日期:——
788. Steroidal αβ-epoxy-ketones. Part I. Rearrangement of 4α,5-epoxy-5α-cholestan-3-one and its 4β,5β-isomer by means of the boron trifluoride–ether complex