摘要:
A process for preparing an azetidinone derivative represented by the formula (1) ##STR1## wherein R.sup.1 represents a substituted or unsubstituted aryl group, a substituted or unsubstituted phenylmethyl group or a substituted or unsubstituted phenoxymethyl group, R.sup.2 represents a hydrogen atom or a group for protecting carboxylic acid and Ar represents a substituted or unsubstituted phenyl group, the process comprising reacting a thiazolineazetidinone derivative represented by the formula (2) ##STR2## wherein R.sup.1 and R.sup.2 are as defined above with a sulfonyl bromide represented by the formula (3)Ar--SO.sub.2 --Br (3)wherein Ar is as defined above in water-containing organic solvent.
摘要:
Disclosed is a method of producing a 3-exomethylenecepham of the formula ##STR1## wherein R.sup.1 is amino or substituted amino and R.sup.2 is a carboxy-protecting group comprising reacting a cephem of the formula ##STR2## wherein R.sup.1 and R.sup.2 are as defined above and X is halogen with lead metal while maintaining the pH of the reaction system at about 0.1 to 8. The cephem (I) may be reacted with a catalytic amount of lead metal or a lead compound in the presence of a metal having a greater ionization tendency than lead.
摘要:
This invention provides azetidinone derivatives represented by the formula ##STR1## and processes for preparing the same. The azetidinone derivatives are used as the intermediates for producing cephalosporin compounds useful as antibiotic agents.
摘要:
This invention provides azetidinone derivatives represented by the formula ##STR1## and processes for preparing the same. The azetidinone derivatives are used as the intermediates for producing cephalosporin compounds useful as antibiotic agents.
摘要:
This invention provides azetidinone derivatives represented by the formula ##STR1## and processes for preparing the same. The azetidinone derivatives are used as the intermediates for producing cephalosporin compounds useful as antibiotic agents.
摘要:
This invention provides a process for preparing a 3-exo-methylenecepham derivative represented by the formula ##STR1## wherein R.sup.1 represents an aralkyl or aryloxymethyl group both of which may be substituted on the aromatic ring, and R.sup.2 represents a carboxyl-protecting group, the process comprising subjecting a compound represented by the formula ##STR2## wherein R.sup.1 and R.sup.2 are as defined above, to a cyclization reaction in an acidic water-containing solvent.
摘要:
This invention provides thiazolinoazetidinone derivatives represented by the formula ##STR1## and processes for preparing the same. The thiazolinoazetidinone derivatives are used as the intermediates for producing cephalosporin compounds useful as antibiotic agents.
摘要:
This invention provides a process for preparing 2-oxycephalosporin derivative represented by the formula ##STR1## wherein R.sup.1 represents hydrogen atom, acyl group, or lower alkoxycarbonyl group optionally substituted with halogen atom, R.sup.2 represents hydrogen atom, halogen atom or acyloxy group optionally substituted with halogen atom, R.sup.3 represents hydrogen atom, lower alkyl group optionally substituted with halogen atom, or phenyl-lower alkyl group which may be optionally substituted with nitro group, halogen atom or lower alkoxy group on the phenyl ring, and R.sup.4 represents lower primary or secondary alkyl or lower alkylcarbonyl, the process comprising electrolytically oxidizing a cephalosporin derivative represented by the formula ##STR2## wherein R.sup.1, R.sup.2 and R.sup.3 are as defined above, in the presence of a lower carboxylic acid or lower primary or secondary alcohol, and a supporting electrolyte.
摘要:
This invention provides a process for preparing a thiazolinoazetidinone derivative represented by the formula ##STR1## wherein R.sup.1 represents aralkyl group or aryloxymethyl group and R.sup.2 represents acyl group, the process comprising electrolyzing a compound of the formula ##STR2## wherein R.sup.1 is as defined above in the presence of a lower fatty acid.
摘要:
This invention provides thiazolinoazetidinone derivatives represented by the formula ##STR1## and processes for preparing the same. The thiazolinoazetidinone derivatives are used as the intermediates for producing cephalosporin compounds useful as antibiotic agents.