From the thin epicuticular wax layer of the tropical fern Nephrolepis
biserrata, three new drimane-type sesquiterpenes (1 beta,11 alpha-diac
etoxy-11,12-epoxydrim-7-ene, 1 beta,6 alpha,11 alpha-triacetoxy-11,12-
epoxydrim-7-ene, 1 beta,3 beta,11 alpha-triacetoxy-11,12-epoxydrim-7-e
ne) were isolated. All these new compounds contain a hemiacetal esteri
fied with acetic acid.