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:
The invention provides a process for preparing a β-lactam derivative represented by the following formula (2) and/or the corresponding enol tautomer (which may be produced depending on its structure), the process comprising oxidizing an alkenyl-substituted β-lactam derivative represented by the following formula (1) in the presence of a ruthenium catalyst or a rhenium catalyst using a periodic acid or a salt thereof:
wherein R¹ is a hydrogen atom, a C₁₋₄ alkyl group or a C₁₋₄ haloakyl group, R² is a hydrogen atom, a C₁₋₄ alkyl group or a phenyl group which may have a substituent, A is a group represented by the formula
a group represented by the formula
or a group represented by the formula
wherein R³ is an amino group or a protected amino group, R⁴ is a hydrogen atom or a group for protecting a carboxylic acid, one of R⁵ and R⁶ is a hydrogen atom and the other is either a hydroxyl group or a protected hydroxyl group, or R⁵ and R⁶, when taken together, represent an oxo group or a group represented by the formula
wherein R⁷ is a hydrogen atom, a C₁₋₄ alkyl group, a phenyl group which may have a substituent, or a group -COOR⁸ wherein R⁸ is a hydrogen atom or a C₁₋₄ alkyl group, X is a hydrogen atom, a halogen atom, a hydroxyl group or a protected hydroxyl group, and Y is a group of the formula -SO₂Ar or -SAr wherein Ar is an aryl group which may have a substituent or a nitrogen-containing aromatic heterocyclic group which may have a substituent; and
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:
A halogenated compound of formula A-X is prepared by reacting in an organic solvent at least one halogenatihg agent selected from halogenating agents of formula and halogenating agents of formula and at least one compound selected from lower alkyl sulfones, lower alkenyl sulfones, aryl sulfones and heterocyclic sulfones at the same time, with a hydroxyl group containing compound of the formula A - OH.
摘要:
The invention provides a process for preparing a β-lactam derivative represented by the following formula (2) and/or the corresponding enol tautomer (which may be produced depending on its structure), the process comprising oxidizing an alkenyl-substituted β-lactam derivative represented by the following formula (1) in the presence of a ruthenium catalyst or a rhenium catalyst using a periodic acid or a salt thereof:
wherein R¹ is a hydrogen atom, a C₁₋₄ alkyl group or a C₁₋₄ haloakyl group, R² is a hydrogen atom, a C₁₋₄ alkyl group or a phenyl group which may have a substituent, A is a group represented by the formula
a group represented by the formula
or a group represented by the formula
wherein R³ is an amino group or a protected amino group, R⁴ is a hydrogen atom or a group for protecting a carboxylic acid, one of R⁵ and R⁶ is a hydrogen atom and the other is either a hydroxyl group or a protected hydroxyl group, or R⁵ and R⁶, when taken together, represent an oxo group or a group represented by the formula
wherein R⁷ is a hydrogen atom, a C₁₋₄ alkyl group, a phenyl group which may have a substituent, or a group -COOR⁸ wherein R⁸ is a hydrogen atom or a C₁₋₄ alkyl group, X is a hydrogen atom, a halogen atom, a hydroxyl group or a protected hydroxyl group, and Y is a group of the formula -SO₂Ar or -SAr wherein Ar is an aryl group which may have a substituent or a nitrogen-containing aromatic heterocyclic group which may have a substituent; and
摘要:
A halogenated compound of formula A-X is prepared by reacting in an organic solvent at least one halogenatihg agent selected from halogenating agents of formula and halogenating agents of formula and at least one compound selected from lower alkyl sulfones, lower alkenyl sulfones, aryl sulfones and heterocyclic sulfones at the same time, with a hydroxyl group containing compound of the formula A - OH.