substitution of the glycosidic moiety of 1 or 2 by ester and ethers , as well as the esterification and etherification of alpha-peltatin ( 4 ) including its glucosidic ethylidene and thenylidene cyclic acetals ( 25 and 26 ) , has afforded compounds of much less activity than that of 1 .
C0014996
ethers
C0000967
acetals