摘要:
Disclosed is a method of producing a 3-exomethylenecepham of the formula wherein R¹ is amino or substituted amino and R² is a carboxyl-protecting group comprising reacting a cephem of the formula wherein R¹ and R² 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:
Disclosed is a method of producing a 3-exomethylenecepham of the formula wherein R¹ is amino or substituted amino and R² is a carboxyl-protecting group comprising reacting a cephem of the formula wherein R¹ and R² 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.