7.7
[]. Richard J Duffy, et al. Asymmetric synthesis, structure, and reactivity of unexpectedly stable spiroepoxy-beta-lactones including facile conversion to tetronic acids: application to (+)-maculalactone A. J Org Chem. 29 Jul ;74():4772-.
H4-H
P26-P264-P2-P+P+P-P+P6+P5-P4+P4-P5+P5+P-P6-P45-P5
GHS5,GHS6
265