Pyridine → HCID 131715965, compound

Participants

Reaction Conditions

Reaction Steps

p-Methoxybenzyl 7-phenylacetamido-3-[2-(4-methylthiazol-5-yl)vinyl]-3-cephem-4-carboxylate (trans-isomer) (0.720 g, 1.28 mmol) was dissolved in methylene chloride (3 ml). The resultant solution was poured into a solution of phosphorus pentachloride (0.800 g, 3.84 mmol) and pyridine (1.04 ml, 12.8 mmol) in methylene chloride (20 ml) at -30° C. The resultant solution was stirred for 3 hours under ice-cooling and poured into methanol (20 ml) as pre-cooled to -30° C., followed by stirring the mixture for 1 hour at ambient temperature. The reaction solution obtained was poured into a mixture of aqueous saturated sodium chloride solution (20 ml) and methylene chloride (20 ml), and the resulting mixture was stirred for 1 hour. The mixture was cooled to stand until it separated into the aqueous phase and organic solvent phase. The aqueous phase separated out was extracted with methylene chloride (20 ml) and the methylene chloride extract was combined with the organic phase mentioned above. The combined organic phase was washed with aqueous saturated sodium hydrogen carbonate solution, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue obtained was purified chromatographically on a column of silica gel (Wako gel C-300) (20 g) as developed with benzene-ethyl acetate (3:1) as the development solvent. The titled compound, 7-amino-3-[2-(4-methylthiazol-5-yl)vinyl]-3-cephem-4-carboxylic acid (trans-isomer) p-methoxybenzyl ester (0.443 g, 78%) was obtained.

Provenance & Evidence