p-Nitrobenzyl 7-{2(2-formamido-4-thiazolyl)-2-methoxyiminoacetamido}-3-chloro-3-cephem-4-carboxylate → 7-{2-(2-Formamido-4-thiazolyl)-2-methoxyiminoacetamido}-3-chloro-3-cephem-4-carboxylic acid

p-Nitrobenzyl 7-{2-(2-formamido-4-thiazolyl)-2-methoxyiminoacetamido}-3-chloro-3-cephem-4-carboxylate (syn isomer, 0.8 g.) was dissolved in a mixed solution of methanol (30 ml.) and tetrahydrofuran (60 ml.). After adding 10% palladium carbon (0.4 g.) to the solution, the mixture was subjected to catalytic reduction at room temperature under atmospheric pressure. The catalyst was filtered off, and the filtrate was concentrated under reduced pressure. Water (30 ml.) was added to the residue and the mixture was adjusted to pH 7.5 with an aqueous solution of sodium bicarbonate. After removing the insoluble substance from the mixture by filtration, the filtrate was washed with ethyl acetate (50 ml.). Ethyl acetate (70 ml.) was added to the solution, and the mixture was adjusted to pH 1.5 with 10% hydrochloric acid and then shaked sufficiently. After the ethyl acetate layer was removed, the aqueous layer was extracted with ethyl acetate (30 ml.) twice. The ethyl acetate layer and the extracts were combined together, washed with a saturated aqueous solution of sodium chloride, dried over magnesium sulfate and then concentrated under reduced pressure to give 7-{2-(2-formamido-4-thiazolyl)-2-methoxyiminoacetamido}-3-chloro-3-cephem-4-carboxylic acid (syn isomer 0.48 g.), m.p. 165° to 174° C. (dec.).

1. customwas subjected to catalytic reduction at room temperature under atmospheric pressure
2. filtrationThe catalyst was filtered off
3. concentrationthe filtrate was concentrated under reduced pressure
4. additionWater (30 ml.) was added to the residue
5. customAfter removing the insoluble substance from the mixture
6. filtrationby filtration
7. washthe filtrate was washed with ethyl acetate (50 ml.)
8. additionEthyl acetate (70 ml.) was added to the solution
9. customAfter the ethyl acetate layer was removed
10. extractionthe aqueous layer was extracted with ethyl acetate (30 ml.) twice
11. washwashed with a saturated aqueous solution of sodium chloride
12. dry with materialdried over magnesium sulfate
13. concentrationconcentrated under reduced pressure

ORD 기록

ord-6e2297bc81134b8ebc235d8ac3e9d231

출처 데이터셋

uspto-grants-1986_08

DOI

10.6084/m9.figshare.5104873.v1

특허 번호

US04604456