氯乙酸乙酯

2-ethoxycarbonyl-1-(2-hydroxyphenyl)-1-α,2α,2aβ,8bβ-tetrahydro-3H-cyclobuta-[c]-chromen-3-one

diethyl t-3,c-4-bis(2-hydroxyphenyl)cyclobutane-r-1,t-2-dicarboxylate