title: The comparative stability of different types of penicillin and cephalosporin N-pyrryl derivatives.
abstract: The kinetics of the decomposition of potassium salts of 4-thia-1-azabicyclo[3.2.0.]heptane-3,3-dimethyl-6-amino-7-oxo-N- [2(1H-pyrrolyl)acetyl] -2-carboxylic acid (6R, trans), 4-thia-1-azabicyclo[3.2.0]heptane-3,3-dimethyl-6-amino-7-oxo-N-[2-phenyl - 2(1H-pyrrolyl)acetyl]-2-carboxylic acid (6R, trans), 5-thia-1-azabicyclo[4.2.0.]oct-2-ene-3- [(acetyloxy)methyl]-7-amino-8-oxo-N-[2(1H-pyrrolyl)acetyl]-2-ca rbo xylic acid (6R, trans), 5-thia-1-azabicyclo[4.2.0.]oct-2-ene-3- [(acetyloxy)methyl]-7-amino-8-oxo-N-[2-phenyl-2(1H-pyrrolyl)acetyl ]- 2-carboxylic acid (6R, trans), 5-thia-1-azabicyclo[4.2.0.]oct-2-ene-7-amino-3-methyl-8-oxo-N- [2(1H-pyrrolyl)-acetyl]-2-carboxylic acid (6R, trans) and 5-thia-1-azabicyclo[4.2.0.]oct-2-ene-7-amino-3-methyl-8-oxo- N-[2-phenyl-2(1H-pyrrolyl)acetyl]-2-carboxylic acid (6R, trans), in aqueous solution at 37 degrees C and at ionic strength of 0.5 mol.l-1 have been studied over the 2.3-11.5 pH range. In all cases, the hydrolysis of these compounds is subject to acid-base catalysis and, in some instances, to a general catalysis by various species present in the buffer solutions. The experimental results have been analyzed and discussed in relation to the hydrolytic mechanisms.
authors: Departmento Interfacultativo de Bioquímica, Facultades de Biologia y Veterinaria, Universidad de León, Spain.
authors: M J
authors: MJ
authors: Arín
authors: M T
authors: MT
authors: Diez
authors: F
authors: F
authors: Salto
mesh_terms: D002511:Cephalosporins / Q000032:analysis / Q000138:chemical synthesis*; D055598:Chemical Phenomena; D002621:Chemistry; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D010406:Penicillins / Q000032:analysis / Q000138:chemical synthesis*; D011758:Pyrroles / Q000032:analysis / Q000138:chemical synthesis
chemical_list: D002511:Cephalosporins; D010406:Penicillins; D011758:Pyrroles