In this work, we explored the activation of a lipoprotein lipase from Burkholderia sp. by surfactants, sugars, and sugar–surfactant combinations for enhancing its activity in organic solvent. The lipase was most strongly activated by the combination of dextrin and anionic surfactant 1. As a result, its turnover frequency in anhydrous toluene reached 420 s–1, which was comparable to its aqueous counterpart. It was also found that a glucosamine-headed surfactant 8 as a molecular mimic of the dextrin-1 combination enhanced the turnover frequency of LPL to the aqueous level. As a rationale for such a high turnover frequency of lipoprotein lipase in anhydrous organic solvent, we speculate that the dextrin-1 couple or its mimic 8 could provide an efficient water-mimicking hydrogen bonding network around the enzyme in addition to the contribution as the oil surrogate, thus leading to a large increase of active enzyme molecules.

Forty-four different secondary alcohols, which can be classified into several types (II-IX), were tested as the substrates of ionic surfactant-coated Burkholderia cepacia lipase (ISCBCL) to see its substrate scope and enantioselectivity in kinetic and dynamic kinetic resolution (KR and DKR). They include 6 boron-containing alcohols, 24 chiral propargyl alcohols, and 14 diarylmethanols. The results from the studies on KR indicate that ISCBCL accepted most of them with high enantioselectivity at ambient temperature and with useful to high enantioselectivity at elevated temperatures. In particular, ISCBCL displayed high enantioselectivity toward sterically demanding secondary alcohols (types VIII and IX) which have two bulky substituents at the hydroxymethine center. DKR reactions were performed by the combination of ISCBCL with a ruthenium-based racemization catalyst at 25-60 °C. Forty-one secondary alcohols were tested for DKR. About half of them were transformed into their acetates of high enantiopurity (>90% ee) with good yields (>80%). It is concluded that ISCBCL appears to be a superb enzyme for the KR and DKR of secondary alcohols.

We explored the kinetic resolution of 31 different diarylmethanols with an activated lipoprotein lipase (LPL-D1) which was about 3000-fold more active than its native counterpart in organic solvent. Most of the substrates tested were accepted by LPL-D1 with good to high enantioselectivity in the kinetic resolution. Next, we explored the dynamic kinetic resolutions (DKRs) of these substrates (24 out of 31) using LPL-D1 and a ruthenium-based racemization catalyst in combination, which provided satisfactory yields (71-96%) and high enantiopurities (90-99% ee). As an illustrative example for the synthetic applications of the DKR procedure, we synthesized L-cloperastine, an antitussive drug, from phenyl-(p-trimethylsilylphenyl)methanol via DKR.

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