Kinetic and thermodynamic analysis for lipase-catalyzed hydrolytic resolution of (R,S)-alcohols though their azolyl carbamates

Bioprocess Biosyst Eng. 2012 Aug;35(6):953-62. doi: 10.1007/s00449-012-0680-x. Epub 2012 Jan 17.

Abstract

A new approach to the lipase-catalyzed hydrolytic resolution of (R,S)-azolyl carbamates for obtaining chiral azolyl carbamates and alcohol is described. With (R,S)-1-phenylethyl azolyl carbamates as the model substrates, the best reaction condition of using (R,S)-1-phenylethyl 4-bromopyrazole carbamate (1) as the substrate in water-saturated diisopropyl ether at 45 °C is selected. The kinetic constants, and hence enantiomeric ratio of 124, are then estimated from the kinetic analysis by considering the alcohol inhibition effect, with which theoretical time-course conversions for both enantiomers are numerically solved and agree with the experimental data. The thermodynamic parameters -ΔΔH and -ΔΔS satisfying a linear enthalpy-entropy compensation relationship of -ΔΔS = -38.84 + 3.29(-ΔΔH) are further estimated. An extension of the resolution platform to (R,S)-4-bromopyrazole carbamates derived from other (R,S)-alcohols (4, 5, 7) is also addressed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carbamates / chemistry*
  • Enzymes, Immobilized
  • Fatty Alcohols / chemistry*
  • Fungal Proteins
  • Kinetics
  • Lipase / chemistry*
  • Models, Chemical*
  • Substrate Specificity
  • Thermodynamics

Substances

  • Carbamates
  • Enzymes, Immobilized
  • Fatty Alcohols
  • Fungal Proteins
  • Novozyme 435
  • Lipase