Pseudomonas fluorescens lipase catalyzed esterification

Scheme 16 Asymmetrization of a double-mejo tetraol by Pseudomonas fluorescens lipase-catalyzed esterification [118].

The synthesis of )-A -BOC-2-hydroxymethyl-2,5-dihydropyrrole )-923 with ee up to 98% was achieved by its irreversible acetylation catalyzed by Pseudomonas fluorescens lipase (Scheme 179) <1998TA403>. Precursor ( )-922 for compound 923 can be easily prepared from commercially available pyrrole-2-carboxylic acid 921 by Birch reduction, followed by esterification and reduction according to literature procedure <1996JOC7664>. 

In case of PLA and other polyester synthesis, lipase catalyst has been nsed and found to be efficient. Lipase is usually an enzyme that catalyzes the hydrotysis of fatly acid esters in living systems and sometimes, can also be used as catalyst for esterification and transesterifications. Lipase enzyme can be derived from Candida cylindracea. Pseudomonas cepacia, Pseudomonas fluorescens, and Porcine pancreas, which are powdery and commercially available crude enzymes (Albertsson and Varma, 2003). 

PEG-lipase from C, cylindracea catalyzes esterification in water-saturated benzene and its substrate specificity was compared with that of PEG-lipase from P. fluorescens [81] and P. fragi [80]. First, esterification from a normal alcohol and a fatty acid with different carbon chain length was tested using three kinds of PEG-lipase, as shown in Fig. 9. Although PEG-lipases from Pseudomonas preferentially catalyzed the esterification reactions from n-alcohol and fatty acid with longer carbon chains, PEG-lipase from C. 

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