反应详情

A solution of 1 g of the product of Step A, 0.38 g of pyridine hydroiodide, 0.63 g of dicyclohexylcarbodiimide, 0.60 g of benzhydryl 3-acetoxymethyl-7-amino-ceph-3-eme-4-carboxylate and 5 ml of anhydrous dimethylformamide was stirred at room temperature for 30 minutes and was vacuum filtered to remove dicyclohexylurea. 100 ml of ether were added to the filtrate and the mixture was stirred for 10 minutes and was vacuum filtered. The product was rinsed with ether and was chromatographed over silica gel. Elution with a 7-1 ethyl acetate-ethanol mixture yielded 0.524 g of the syn isomer of benzhydryl 3-acetoxymethyl-7-[2-2tritylamino-4-thiazolyl)-2-(2-morpholinoethoxyimino)-acetamido]-ceph-3-eme-4-carboxylate hydroiodide melting at 167° C. (decomposition).

1. filtrationfiltered
2. customto remove dicyclohexylurea
3. addition100 ml of ether were added to the filtrate
4. filtrationfiltered
5. washThe product was rinsed with ether
6. customwas chromatographed over silica gel
7. washElution with a 7-1 ethyl acetate-ethanol mixture