Chemical transformation and biological activities of ambrein, a major product of ambergris from Physeter macrocephalus (sperm whale).

Ten new derivatives (2-11) of ambrein (1), isolated from ambergris, were prepared by chemical transformation. Oxidation and/or cyclization were effected by reactions with selenium oxide or p-toluenesulfonyl chloride or with the use of shortwave UV light. The structures of 2-12 were elucidated by spectroscopic analysis, with the structure and relative configuration of 9 confirmed by single-crystal X-ray crystallography. The cytotoxic activities of 1-12 were investigated against human liver carcinoma (Hepa59T/VGH), colon adenocarcinoma (WiDr), lung carcinoma (A-549), and human breast adenocarcinoma (MCF-7) cell lines. The anti-inflammatory activities of 1-11, in terms of the inhibition of human neutrophil function, were also evaluated.