Process for the preparation of 7-beta-aminocephem-3-01-4-carboxylic acid compounds

• Main Author: ROBERT BURNS WOODWARD
• Format: Patent
• Language: English
• Published: 28.12.1979
• Subjects: CHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION ORPROCESSING OF GOODS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; HETEROCYCLIC COMPOUNDS; METALLURGY; ORGANIC CHEMISTRY; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE

The preparation of 7-ss-amino-3-cephem-3-01-4-carboxylic acid compounds of the formula wherein Ra DIVIDED 1 represents hydrogen or an amino-protecting group RA DIVIDED 1, and Rb DIVIDED 1 represents hydrogen or an acyl group Ac, or Ra DIVIDED 1 and Rb DIVIDED 1 together represent a bivalent amino-protecting group, RA DIVIDED 2 represents hydroxyl, halogen or a radical which together with the carbonyl grouping -C(=O)- forms a protected carboxyl group, and R3 represents an optionally substituted alpha -phenyl-lower alkyl group, and of the corresponding 2-cephem compounds, is effected by treating a corresponding 2-(3-amino-2-oxo-4-thio-1-azetidinyl)-3-substituted-hydroxycrotonic acid compound with a base. Compounds obtained which have a salt-forming group may be converted to a salt, and salts obtained may be converted to the free compound. The compounds obtained according to the invention can further be oxidised to the corresponding 1-oxide. The enol derivatives thus prepared exhibit antimicrobial properties or can be used as intermediates for the preparation of compounds having such properties.