ClC(OCC(C)C)=O.[C:9]1([C:15]2[N:16]=[C:17]([CH2:26][CH2:27][C:28]([OH:30])=O)[NH:18][C:19]=2[C:20]2[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=2)[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=1.[CH2:31]([N:33](CC)CC)C.Cl.CN.N12CCCN=C1CCCCC2>CN(C)C=O.O>[CH3:31][NH:33][C:28](=[O:30])[CH2:27][CH2:26][C:17]1[NH:16][C:15]([C:9]2[CH:10]=[CH:11][CH:12]=[CH:13][CH:14]=2)=[C:19]([C:20]2[CH:21]=[CH:22][CH:23]=[CH:24][CH:25]=2)[N:18]=13.2 ml (0.024 mol) of isobutyl chloroformate are added dropwise at -5° to a solution of 7.0 g (0.024 mol) of 4,5-diphenylimidazole-2-propionic acid and 3.36 ml (0.024 mol) of triethylamine in 80 ml of dimethylformamide. After stirring at 0°-5° for 30 minutes 1.64 g (0.024 mol) of methylamine hydrochloride and 3.36 ml (0.024 mol) of triethylamine in 32 ml of dimethylformamide and 1.65 ml of water are added. The temperature is then left to rise to room temperature and the mixture is stirred for a further 20 hours. After concentration under reduced pressure the residue is boiled up in 250 ml of methanol and treated with 3.6 ml (0.024 mol) of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), whereby a clear solution results. 4.8 g of N-methyl-4.5-diphenylimidazole-2-propionamide, m.p. 195°-200° (dec.), result by cooling in an ice-bath. From the mother liquor there are obtained by concentration and treatment with water a further 2 g of the same product, m.p. 195°-200°. Total yield: 6.8 g (93%).
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