methyl 8-acetyl-10,10-dimethoxy-9-oxodecanoate

methyl 7-(1-hydroxy-2-oxocyclopentyl)heptanoate

二溴戊烷

(5-溴代戊)丙二酸二乙酯

7-(2-bromo-5-oxo-1-cyclopentenyl)heptanoic acid