Influence of the Nature of the Solvent on the Enantioselectivity of Lipase-Catalyzed Transesterifications: A Comparison between the Lipases from Porcine Pancreas and Pseudomonas Fluorescens
作者:Bernardo Herradon
DOI:10.1021/jo00089a040
日期:1994.5
Regio- and enantioselective esterifications of polyoxygenated compounds catalyzed by lipases
The lipase catalyzed esterifications of derivatives of propane-1,2,3-triol and butane-1,2,4-triol in organic solvents have been studied. The influence of several factors (lipase source, organic solvent, additives and structural variations in die substrates) on the selectivity have been investigated. Good levels of regio- and enantioselectivity have been achieved, providing practical methods for the synthesis of these chiral building blocks.
Herradon B., J. Org. Chem, 59 (1994) N 10, S 2891-2893
作者:Herradon B.
DOI:——
日期:——
A Total Synthesis of Hydroxylysine in Protected Form and Investigations of the Reductive Opening of <i>p</i>-Methoxybenzylidene Acetals
A synthesis of (2S,5R)-5-hydoxylysine, based on (R)-malic acid and Williams glycine template as chiral precursors, has been developed. This afforded hydroxylysine, suitably protected for direct use in peptide synthesis, in 32% yield over the 13-step sequence. Regioselective reductive opening of a p-methoxybenzylidene acetal and alkylation of the Williams glycine template were key steps in the synthetic
Biocatalytic synthesis of chiral polyoxygenated compounds: modulation of the selectivity upon changes in the experimental conditions
作者:Bernardo Herradón、Serafín Valverde
DOI:10.1016/0957-4166(94)80118-5
日期:1994.8
transesterification reaction catalyzed by Pseudomonasfluorescenslipase (PFL) in organicsolvents. The influence of the solvent on the enantioselectivity has been thoroughly examined. It has been found that the enantioselectivity depends on both the hydrophobicity and the polarity of the solvent in a semi-quantitative way. The influence of other experimental variables (temperature, amounts of lipase and acylating