3,5-Dimethylpyrrole-2,4-dicarboxylic acid 2-tert-butyl ester 4-ethyl ester2-tert-Butyl 4-ethyl 3,5-dimethyl-1H-pyrrole-2,4-dicarboxylate2-tert-Butyl 4-ethyl 3,5-dimethyl-1H-pyrrole-2,4-dicarboxylate 98%3,5-DIMETHYL-1H-PYRROLE-2,4-DICARBOXYLIC ACID 2-TERT-BUTYL ESTER 4-ETHYL ESTER