Sir: Among natural sesquiterpene alcohols, those possessing the A6-protoilludane skeleton (1) have attracted attention as synthesis targets because of the unique methylene- cyclobutane structural feature.'Illudol (2), a member of this class, has recently been obtained by total synthesis2 Fomannosin (3) has been shown to arise through protoilludane precursors in nature3 and has not yet been successfully~ ynthesized.~ The relation ...
