1: 1,4-dihydro-2,6-dimethyl-5-methoxy-carbonyl-4-(3-nitrophenyl)pyridine-3-carboxylic acid With thionyl chloride; N,N-dimethyl-formamide in dichloromethane 1 h; Sonographic reactionCooling with ice; 2: 3-hydroxy-N-phenylmethylpiperidine in dichloromethane 2.5 h; Cooling with iceSonographic reaction;