【文章名】Isolation, Biological Significance, Synthesis, and Cytotoxic Evaluation of New Natural Parathiosteroids A-C and Analogues from the Soft Coral Paragorgia sp.
Isolation, Biological Significance, Synthesis, and Cytotoxic Evaluation of New Natural Parathiosteroids A-C and Analogues from the Soft Coral Paragorgia sp.
作者
Poza, Javier Jesus;Fernandez, Rogelio;Reyes, Fernando;Rodriguez, Jaime;Jimenez, Carlos;
[摘要]：Three unusual new steroid thioesters, parathiosteroids A-C (I-III), were isolated from the 2-propanol ext. of the soft coral Paragorgia sp. collected in Madagascar. Their structures, detd. by detailed spectroscopic anal., were confirmed by synthesis and represent the first isolation of natural steroids bearing a C22 thioester in their side chain. These compds. displayed cytotoxicity against a panel of three human tumor cell lines at the micromolar level. The prepn. of several analogs revealed structure/activity relationships in this type of steroids, for example, that the XCH2CH2NHCOCH3 moiety (X = S, O, NH) in the side chain is essential for the antiproliferative activity, and a low degree of oxidn. in the A-ring results in higher bioactivity. These natural products could be biosynthetic intermediates in the steroid side chain degrdn. pathway involving activation with CoA and b-oxidns.
