Study of Catalytic Hydrogenation and Methanol Addition to α-Methylene-γ-Lactone of Eremanthine Derivatives

Abstract

The sesquiterpene lactones guaia-1(10),11(13)-dieno-4α-hydroxy,9α-acetyl-15-iodine-12,6α-lactone (2), guaia-1(10),4(15),11(13)-trieno-9α-hydroxy-12,6α-lactone (3), (11S)-guaia-4(15),10(14)-dieno-9α-hydroxy-13-methoxy-12,6α-lactone (4), (11S)-guai-1(10)-eno-4α,9α-dihydroxy-13-methoxy-12,6α-lactone (5), and guaia-1(10),11(13)-dieno-4α,9α-dihydroxy-15-iodine-12,6α-lactone (6) were previously obtained starting from the natural product eremanthine (1). In this paper we report the catalytic hydrogenation reactions of allylic derivatives 2–5 and the methanol addition to α-methylene-γ-lactone of the iodohydrin 6.