Dicyclohexylcarbodiimide → HCID 12769261, compound

Participants

Reaction Steps

A solution of Z-2-phenyl-2-(2-ureidocarbonylprop-2-yloxyimino)acetic acid (460 mg) in dichloromethane (6 ml) and dimethylformamide (2 ml) was added slowly to a stirred solution of dicyclohexylcarbodiimide (370 mg) and diphenylmethyl (6R,7R)-3-(1-methyltetrazol-5-ylthiomethyl)-7-aminoceph-3-em-4-carboxylate (790 mg) in dichloromethane (10 ml) and dimethylformamide (3 ml) and the mixture was stirred for 20 hr. The solution was filtered, the filtrate was evaporated, and the residue was dissolved in ethyl acetate (50 ml). The filtered solution was washed with 2N- hydrochloric acid (2×15 ml) and saturated sodium hydrogen carbonate solution (2×15 ml), dried (Na2SO4) and evaporated. The residue was purified on silica gel plates in light petroleum-ethyl acetate (1:1 v/v) to give the ester, 580 mg, λmax (Nujol) 3400, 3280 (NH, NH2), 1788 (β-lactam), 1720, 1710 (--CO2R), 1685, 1670 cm-1 (--CONHCONH2, --CONH--), τ(DMSO d6) 0.60 (--CONHCO--), 8.59 (--C(Me)2 --), 2.0-2.9 (Phenyls), --0.06 (--CONH--), 3.87 (7 H), 4.62 (6H), 5.9, 6.5 (2--CH2 --), 5.59, 5.79 (3--CH2 --), 6.09 (--N--Me), 3.0 (--CH Ph2).

Provenance & Evidence