Acetate → HCID 131710772, compound

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Reaction Steps

A solution of sodium 3-acetoxymethyl-7β-[2-hydroxyimino-2-(thien-2-yl)acetamido]ceph-3-em-4-carboxylate (syn-isomer; 0.89 g) in dimethylformamide (11 ml.) containing triethylamine (0.22 g) was treated with 2-chloroethylisocyanate (0.25 g). The solution was allowed to stand at room temperature for thirty minutes, then at 5° for a further hour. It was poured into cold (5°) 2N hydrochloric acid, extracted three times with ethyl acetate, and the combined extracts washed with 2N-hydrochloric acid then water then extracted three times with a cold (5°) saturated aqueous sodium bicarbonate solution. The combined aqueous extracts were washed with ethyl acetate, acidified (2N-hydrochloric acid) and apidly extracted with ethyl acetate. The combined extracts were dried, concentrated to ca. 5 ml., and the concentrate added dropwise to petroleum (b.p. 40°-60° 250 ml.) The precipitated solid was filtered and dried to give the title acid (0.8 g; 76%), [α]D +33° (c 0.7 DMSO) λmax. (pH 6 phosphate buffer) 264 nm. (ε 17,200), νmax. (Nujol), 1786 (β-lactam), 1734 (acetate), 1682 and 1508 cm.-1 (CONH), τ (DMSO-d6) values include 0.12 (doublet J 9 Hz; NH), 2.12, 2.56, 2.74 (three guartets; thienyl protons), 7.97 (s; OCOCH3).

Provenance & Evidence