Pyridine → HCID 131713647, compound

Participants

Reaction Steps

In the manner described in Example 12, 3.2 g of 3-[(1-methyl-1H-tetrazol-5-yl)-thiomethyl]-7β-[(2R)-2-(4-aminophenyl)-2-(4-ethyl-2,3-dioxopiperazine-1-carboxamido)-acetamido]-3-cephem-4-carboxylic acid diphenylmethyl ester p-toluenesulphonate are reacted with 2.65 g of (2R)-2-BOC-amino-2-diphenylmethoxycarbonylethoxycarbonyl chloride and 0.67 ml of pyridine in 65 ml of tetrahydrofuran and worked up. The resulting crude product is chromatographed over 400 g of silica gel, and 500 ml fractions are taken. The fractions are eluted with toluene/ethyl acetate (1:1). By reprecipitating fractions 7-28 from CH2Cl2 /ether/hexane, 3-[(1-methyl-1H-tetrazol-5-yl)-thiomethyl]-7β-{(2R)-2-[4-((2R)-2-BOC-amino-2-diphenylmethoxycarbonylethoxycarbonylamino)-phenyl]-2-(4-ethyl-2,3-dioxopiperazine-1-carboxamido)-acetamido}-3-cephem-4-carboxylic acid diphenylmethyl ester is obtained. [α]D20 =-69°±1° (1.00% in CDCl3).

Provenance & Evidence