1,2,3,4-Cyclobutanetetracarboxylic acid, tetramethyl ester, (1.alpha.,2.alpha.,3.beta.,4.beta.)- 1,2,3,4-Cyclobutanetetracarboxylic acid, tetramethyl ester, cis-1,2,trans-1,3,trans-1,4- 1032-95-7 NSC122966 cis, trans, cis-1,2,3,4-Cyclobutanetetracarboxylic acid tetramethyl ester