(2,2,5-Trimethyl-4-oxo-1-piperidyl)maleic acid diethyl ester (E)-2-(2,2,5-Trimethyl-4-oxo-1-piperidinyl)-2-butenedioic acid diethyl ester 110998-14-6 2-BUTENEDIOIC ACID, 2-(2,2,5-TRIMETHYL-4-OXO-1-PIPERIDINYL)-, DIETHYL ESTER, (E) 2-Butenedioic acid, 2-(2,2,5-trimethyl-4-oxo-1-piperidinyl)-, diethyl ester, (E)- BRN 5591642