Central pathway of photochemical decomposition of the 10-membered ring
analog 9 proved to be a fragmentation reaction of naphthoate ester, a
n analog to Norrish Type II split, leading to the formation of unstabl
e fulvene derivative 10 and 2-hydroxy-7-methoxy-5-methyl-1-naphthoic a
cid 4, which implied the mechanism of photodecomposition of neocarzino
statin chromophore 1.