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Abstract: The bioactive alkaloid (−)-lobeline was synthesized via the stereoselective acylation (desymmetrization) of meso-lobelanidine by vinyl acetate in the presence of Candida antarctica lipase B. [Copyright &y& Elsevier]

Abstract: Enzymatic acylation is commonly used for the kinetic resolution of alcohols and amines. The simple acyl group introduced during the enzymatic reaction is usually removed or replaced by another group. Retention of more complex acyl moieties as part of the target structures would be a more efficient strategy. We have studied the enantioselective acylation of a model alcohol substrate, 1-phenylethanol, with vinyl esters bearing various functionality on the acyl moieties in the presence of three lipases (Candida antarctica, Candida rugosa and Burkholderia cepacia) frequently used in organic synthesis. C. antarctica lipase is the most versatile lipase for this type of biotransformations. We applied this strategy to the synthesis of a protein kinase C ligand and a natural product, phoracantholide. [Copyright &y& Elsevier]

Abstract: 2-Substituted glycerol derivatives 4a–g were resolved by acylation with vinyl butyrate in the presence of lipases in organic media. The reverse reaction, the enzymatic hydrolysis of the corresponding butyrates 5a–g, was also highly stereoselective and provided the opposite enantiomers. High enantioselectivities (ee >90%) and good isolated yields were obtained for all substrates using the appropriate lipase. Pseudomonas cepacia lipase or the closely related Pseudomonas sp. lipase were the most efficient enzymes for the resolution of substrates bearing smaller aliphatic groups. Candida antarctica lipase B was more suitable as the biocatalyst in the resolution of more sterically demanding aromatic substrates. 2-Benzylglycerol derivatives were resolved in the presence of Rhizopus sp. lipase. [Copyright &y& Elsevier]

Abstract: The enantioselective acylation (desymmetrization) of meso-7-azabicyclo[2.2.1]heptanediol 2 by vinyl acetate in the presence of Candida antarctica lipase B gave the corresponding (1R,2R,3S,4S)-monoester 4 in high enantiomeric purity (ee⩾98%). [Copyright &y& Elsevier]