Carcinogenesis vol.17 no.9 pp.2009-2012, 1996 Synthesis and mutagenicity of some cydopenta[c]phenanthrenes and indeno[c]phenanthrenes

Abstract

To whom correspondence should be addressed An efficient two-step synthesis of 8(7/)-9,10,ll,12-tetra-hydrodicyclopenta[a,c]phenanthren-7-one, based on the high pressure Diels-Alder cycloaddition of 4-acetoxy-2-cyclopenten-1-one with l-(l-naphthyJ)cyclopentene and a subsequent dehydrogenation-aromatization reaction, is reported. Further, the synthesis of two cyclopenta[c]-phenanthrenes and indeno[c]phenanthrenes is described. Structural analysis of the new products by XH and 13C NMR spectroscopy is presented. The mutagenic activity of the compounds in Salmonella typhimurium was estimated by Ames ' test. Three compounds were shown to be muta-genic for the strain TA 100. The mutagenic activities exhibited by cyclopenta[c]phenanthrenes are compared with those shown by the related cyclopenta[a]phenan-threnes and then discussed with respect to the effect of the cyclopentane ring facing the bay region. Indeno[c]phen-anthrenes are mostly inactive. The effect of benzoannulation on the mutagenic activities of cyclopenta[c]phenanthrenes is discussed