Approach to the synthesis of side-chain eudesmanediols: synthesis of kudtriol from 1-(α)-santonin

摘要: The synthesis of an eudesmanic alcohol, kudtriol (1), is described along with its 11-deoxy analogue (19) starting from 1 -(α)-santonin in ten steps. known intermediate methyl (11S)-3-oxoeudesm-4-en-12-oate (5b) was taken through the new intermediates (11S)-eudesm-4-en-12-oate (6), (11S)eudesm-4-en-12-al (17), 11-hydroxyeudesm-4-en-12-al (18), and eudesm-4-ene-11,12-diol (8). construction side-chain diol moiety last mentioned achieved by application Vedejs' enolate hydroxylation on (17). sensitised photo-oxygenation cum reduction sequence transformed ene (8) into title compound (1). A similar (11S)eudesm-4-en-12-ol (16) resulted 11-deoxykudtriol (19).