Synthesis of substituted 3-cyano-2-pyridones: Part III - Enzyme kinetics

Lipases from Candida cylindracea and hog pancreas have been used to study t he reaction kinetics of enzyme catalysed synthesis of substituted 3-cyano-2 -pyridones by cyclization of 1,3-diketones with cyanoacetamide. Influence o f diketone:cyanoacetamide ratio, enzyme:substrate ratio, temperature, organ ic media, type of enzyme and alkyl substituents on the reaction is reported . Kinetics for allosteric enzymes is indicated and apparent rate constants are calculated. However, the activation parameters obtained are more compat ible with the Henry-Michaelis-Menten approach and the corresponding kinetic s is also discussed.