反应详情

温度

16 °C

A mixture of 1.69 g of the product of Step A, 0.685 g of pyridine hydroiodide, 1.16 g of benzhydryl 3-acetoxymethyl-7-amino-ceph-3-eme-4-carboxylate and 1.36 g of dicyclohexylcarbodiimide was admixed with 17 ml of dimethylformamide and the mixture was cooled to 16° C. for 30 minutes and was then vacuum filtered. 400 ml of ether were added to the filtrate and the mixture was stirred for 5 minutes and allowed to stand for one hour. The mixture was decanted and the gum was washed with ether and was added to 50 ml of ether. The mixture was kneaded until concretization and was vacuum filtered. The product was washed with ether and dried to obtain 1.92 g of raw product which was chromatographed over silica gel. Elution with a 91-9 chloroform-acetonitrile mixture yielded 790 mg of amorphous syn isomer of benzhydryl 3-acetoxymethyl-7-[2-(2-tritylamino-4-thiazolyl)-2-(2-thiocyanatoethoxyimino)-acetamido]-ceph-3-eme-4-carboxylate

1. filtrationvacuum filtered
2. addition400 ml of ether were added to the filtrate
3. waitto stand for one hour
4. customThe mixture was decanted
5. washthe gum was washed with ether
6. additionwas added to 50 ml of ether
7. filtrationfiltered
8. washThe product was washed with ether
9. customdried
10. customto obtain 1.92 g of raw product which
11. customwas chromatographed over silica gel
12. washElution with a 91-9 chloroform-acetonitrile mixture