Process for preparing cephalosporins
US4036835A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 1, 1976 |
| Grant date | Jul 19, 1977 |
| Priority date | — |
| Expiry date | Mar 1, 1996 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07F9/2458
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for preparing cephalosporins of structure: ##STR1## where R is hydrogen, C.sub.1 to C.sub.4 alkyl, cyano-methyl-, thienyl-methyl, furyl-methyl-, naphthyl-methyl-, phenyl-methyl-, phenoxy-methyl-, phenyl-isopropyl-, phenoxy-isopropyl-, pyridyl-4-thiomethyl-, and tetrazolyl-1-methyl; R.sup.1 is hydroxyl, C.sub.2 to C.sub.4 alkoxy, trichloroethoxy-, benzyloxy-, p-methoxy-benzyloxy-, p-nitrobenzyloxy-, benzhydryloxy-triphenylmethoxy-, phenacyloxy-, and p-halophenacyloxy; Z is hydrogen, hydroxyl, --O--alkyl, --O--CO--alkyl, --Br, --I, --N.sub.3, --NH.sub.2, --O--CO--CH.sub.3, --O--CO--NH.sub.2 and an --S--mononuclear nitrogen heterocyclic ring; Wherein a compound of structure ##STR2## is reacted in a suitable solvent at a temperature between -20.degree. C and +80.degree. C, in the presence of an aqueous organic or inorganic acid with an azoderivative of the formula: ##STR3## where R.sup.2 and R.sup.3 are equal or different and represent lower alkyl, a mononuclear aryl ring, CN--, a mononuclear heterocyclic ring, or the radicals --COR.sup.4, --COOR.sup.4, ##STR4## --CONHR.sup.4, or R.sub.2 and R.sub.3 together may represent the residues: ##STR5## where T represents >CH.sub.2, >…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.