Patent · US Expired

Preparation of 3-substituted cephalosporins

US4301280A · kind A · utility

2Cited by
3References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 1, 1980
Grant dateNov 17, 1981
Priority date
Expiry dateMay 1, 2000

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P20/55
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

There is described a process for preparing an enamine of formula (IX): ##STR1## where R.sup.2 is a carboxylic acid protecting group and R.sup.3 is the residue of a carboxylic acid derived acyl group and where R.sup.5 and R.sup.6 are the same or different C.sub.1-4 alkyl or C.sub.7-10 aralkyl groups; or taken together with the adjacent nitrogen atom form a heterocyclic ring containing from 4 to 8 carbon atoms and optionally a further heteroatom selected from oxygen and nitrogen; by reacting a compound of formula (XII): ##STR2## with an amine of formula HNR.sup.5 R.sup.6, the reactant of formula (XII) being prepared by reaction of an appropriate enol derivative with a phosphorus reagent. The enamines of formula (IX) are useful in the preparation of 3-hydroxycephalosporins.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.