tert-Butyl 4-(2-ethoxy-2-oxoethylidene)piperidine-1-carboxylate;(1-Boc-piperidin-4-ylidene)acetic Acid Ethyl Ester;[1-(tert-Butoxycarbonyl)piperidin-4-ylidene]acetic Acid Ethyl Ester;4-(2-Ethoxy-2-oxoethylidene)piperidine-1-carboxylic Acid tert-Butyl Ester;Ethyl (1-Boc-piperidin-4-ylidene)acetate;Ethyl [1-(tert-Butoxycarbonyl)piperidin-4-ylidene]acetate;4-(Ethoxycarbonylmethylene)-1-(tert-butoxycarbonyl)piperidine;4-[(Ethoxycarbonyl)methylene]piperidine-1-carboxylic acid tert-butyl ester;[1-(tert-Butoxycarbonyl)piperidin-4-ylidene]acetic acid ethyl ester;tert-Butyl 4-(2-ethoxy-2-oxoethylidene)-1-piperidinecarboxylate;tert-butyl 4-(ethoxycarbonylmethylene)piperidine-1-carboxylate;tert-butyl 4-(2-ethoxy-2-oxoethylidene)-1-piperidinecarboxylate;t-butyl 4-(2-ethoxy-2-oxoethylidene)tetrahydropyridine-;ethyl [1-(tert-butoxycarbonyl)piperidin-4-ylidene]acetate;1-tert-butoxycarbonyl-4-ethoxycarbonylmethylenepiperidine;(1-tert-butoxycarbonylpiperidin-4-ylidene)acetic acid ethyl ester;tert-Butyl 4-(2-ethoxy-2-oxoethylidene)tetrahydro-1(2H)-pyridinecarboxylate;Ethyl 2-(1-Boc-4-piperidylidene)acetate