4-(4-Fluoro-phenyl)-piperidine-1,3-dicarboxylic acid 1-tert-butyl ester 3-ethyl ester

(3R,4S)-4-(4-Fluoro-phenyl)-piperidine-3-carboxylic acid {(R)-3-[6-(4-chloro-phenylsulfanyl)-2-(4-methoxy-phenyl)-3-oxo-2,3-dihydro-pyridazin-4-yl]-1-methyl-propyl}-amide