反应详情

The combined extracts (upper layer + extracted layer) were combined and by adding cold methanol, the total volume was brought to 200 ml. This methanolic solution containing cefatrizine was added slowly to methanol, kept at a constant pH 5.1 by automatic addition of 10% triethylamine in methanol. The mixture was further stirred for one hour and then kept overnight at about -15° C. The crystalline precipitate was filtered, washed with 95% methanol and 99% methanol, respectively and dried in vacuo to constant weight. The yield was 8.408 g. of 7-[D-α-amino-p-hydroxyphenylacetamido]-3-[(1H)-1,2,3-triazol-5-yl-thiomethyl]-3-cephem-4-carboxylic acid-methanolate. The PMR spectrum of the product indicated an exact 1:1 ratio between cefatrizine and methanol, while crude yield of cefatrizine methanolate was 63.83%.

1. waitkept overnight at about -15° C
2. filtrationThe crystalline precipitate was filtered
3. washwashed with 95% methanol and 99% methanol
4. customrespectively and dried in vacuo to constant weight