Urea → HCID 131723233, compound

Participants

Reaction Steps

A solution of N-benzyl-2-(R,S)-(4-cyano-benzyl)-malonamic acid (10 g, 32.4 mmol), (S)-amino-cyclohexyl-acetic acid methyl ester (5.94 g, 34.7 mmol), diisopropylethyl-amine (6.45 ml, 37.9 mmol), 3-hydroxy-3H-benzo[d][1,2,3]triazin-4-one (1.32 g, 8.1 mmol), and dimethylformamide (100 ml) was cooled to 10° C. A solution of dicyclohexyl-carbodiimide (7.83 g, 37.9 mmol) in toluene (10 ml) was added dropwise and the reaction mixture stand over night. The precipitated urea was sucked off, the filtrate was evaporated in vacuo, solved in ethyl acetate, washed with saturated sodium hydrogen carbonate-solution and brine, dried, and evaporated in vacuo. Crystallization from n-heptane/isopropanol gave 9.91 g (66%) of the desired product. mp.: 170-174° C., MS m/z: 462 (M+H)+.

Provenance & Evidence