70356-03-5Relevant articles and documents
Cefaclor preparation and preparation method thereof
-
Paragraph 0033; 0088; 0089, (2017/04/29)
The invention discloses a cefaclor preparation and a preparation method thereof. The preparation method comprises: preparing cefaclor crystal, pretreating a main material and auxiliary materials, weighing, mixing, forming, and packaging; wherein the preparation of the cefaclor crystal includes subjecting 7-ACCA and potassium (R)-[(3-ethoxy-1-methyl-3-oxoprop-1-enyl)amino]phenylacetate to silylation, acylation, condensation, acid hydrolysis, extraction and cleaning, decoloring, and crystallization; the preparation comprises the cefaclor crystal as the main material and auxiliary materials, the cefaclor crystal is /=33 degrees in angle of repose, 0.50-0.60 g/m in bulk density, 0.70-0.80 g/ml in compactness and 40-60 Mum in D10 of particle size distribution, 120-140 Mum in D50 and 210-230 Mum in D90. The conversion rate of cefaclor in chemical synthesis is increased, reaction conditions are simplified, the crystal form and particle size distribution of the cefaclor crystal are improved, and the quality of finished cefaclor crystal is improved.
Process for the preparation of 3-chloro-cefem compounds
-
, (2008/06/13)
The process comprises a series of stages essentially comprising the protection of the functional groups of the side chain of Ampicillin, esterification of the acid group, oxidation to sulphoxide, expansion of the thiazole ring to a thiazine ring, ozonolysis of the exomethylene cefam derivative obtained, substitution of the hydroxyl group by chlorine and de-protection of the functional groups, in which the order of some stages can be varied without affecting the final result.