5-Cyanomethyl-3-(2-methoxycarbonyl-ethyl)-4-methyl-1H-pyrrole-2-carboxylic acid tert-butyl ester

5-{2-Amino-1-[(R)-3-methoxycarbonylmethyl-3-methyl-5-oxo-pyrrolidin-(2Z)-ylidene]-ethyl}-3-(2-methoxycarbonyl-ethyl)-4-methyl-1H-pyrrole-2-carboxylic acid tert-butyl ester

(3R,4E)-9-tert-Butoxycarbonyl-5-cyano-8-(2-methoxycarbonylethyl)-3-methoxycarbonylmethyl-3,7-dimethyl-2,3-dihydrodipyrrin-1(10H)-one