Center for Biological NMR, P.O. Box 300012, Department of Chemistry, Texas A & M University, College Station, Texas 77842-3012, U.S.A. Department of Applied Science, Okayama University of Science, 1-1 Ridai-cho, Okayama 700, Japan 700-0005 Manuscript received 9 November 1998 Catharanthus roseus cultured cells produce several new oxidized products from (5R)-(+)-pulegone and (2S, 5R)-(—)-menthone, in some of which a double bond migration has occurred. Products were identified using NMR and mass spectrometry. The pleasant fragrances of some of the products suggest possible use as perfumery agents.