[S:1](/[CH:4]=[CH:5]\[C:6]([OH:8])=O)[C:2]#[N:3].C(N(CC)CC)C.ClC(OCC)=O.[NH:22]1[CH2:27][CH2:26][CH2:25][CH2:24][CH2:23]1>C1(C)C=CC=CC=1>[S:1](/[CH:4]=[CH:5]\[C:6]([N:22]1[CH2:27][CH2:26][CH2:25][CH2:24][CH2:23]1)=[O:8])[C:2]#[N:3]To a stirred suspension of compound 2 (3.06 g., 0.023 mole) in 60 ml of dry toluene, triethylamine (2.35 g., 0.023 mole) in 10 ml of dry toluene was added dropwise, keeping the temperature of the mixture at 0°-5° C. To the resulting solution was added dropwise, ethyl chloroformate (2.53 g., 0.023 mole) in 15 ml of dry toluene at 0°-5° C. After stirring the mixture for 15 minutes, piperidine (2.0 g., 0.023 mole) in 15 ml of dry toluene was added dropwise at 0°-5° C. The mixture was allowed to warm to room temperature, stirred for an additional 2 hours and filtered. The filtrate was washed with water, dried (MgSO4) and concentrated to give an oil which solidified, 2.6 g. The solid was recrystallized from ethanol: mp 88°-90° C.; IR (KBr) 2175, 1630 cm-1
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