S. Gurunath et al., ALUMINA-CATALYZED DERIVATIZATION OF SESQUITERPENE LACTONES, Indian journal of chemistry. Sect. B: organic chemistry, including medical chemistry, 36(11), 1997, pp. 1047-1049
Two new derivatives 2 and 4 have been obtained by the alumina-catalyse
d reaction of methanol with sesquiterpene lactones 1 and 3 previously
isolated from Cyathocline species. The structures of 2 and 4 have been
elucidated by extensive NMR studies.