反应详情

A mixture of 2.775 g of the product of Step C, 14 ml of acetone and 4.5 ml of N hydrochloric acid was stirred for 2 hours at room temperature and the acetone was evaporated under reduced pressure. 20 ml of ethyl acetate were added thereto and the mixture was stirred and decanted. The organic phase was washed 4 times with 10 ml of slightly salted water and the wash waters were extracted with 5 ml of ethyl acetate. The combined organic phases were dried and vacuum filtered and the filter was rinsed with ethyl acetate. The filtrate was evaporated to dryness under reduced pressure and the residue was taken up in ether. Crystallization and efflorescence occured and the mixture was vacuum filtered. The product was rinsed with ether and dried to obtain 1.88 g of the syn isomer of diphenylmethyl 7-[2-(2-tritylamino-4-thiazolyl)-2-hydroxyimino-acetamido]-3-acetoxymethyl-ceph-3-eme-4-carboxylate with Rf=0.5 (ether containing 20% of acetone).

1. customthe acetone was evaporated under reduced pressure
2. addition20 ml of ethyl acetate were added
3. stirringthe mixture was stirred
4. customdecanted
5. washThe organic phase was washed 4 times with 10 ml of slightly salted water
6. extractionthe wash waters were extracted with 5 ml of ethyl acetate
7. customThe combined organic phases were dried
8. filtrationvacuum filtered
9. washthe filter was rinsed with ethyl acetate
10. customThe filtrate was evaporated to dryness under reduced pressure
11. customCrystallization and efflorescence
12. filtrationfiltered
13. washThe product was rinsed with ether
14. customdried