Candida antarctica lipase (CAL) catalyzed amidation of Cbz-glutamic acid diesters takes place in a regioselective way to give the corresponding monoamide derivatives. The regioselectivity was found to be dependent on the reacting Glu enantiomer. Thus, amidations of Cbz-L-Glu diesters regiospecifically afforded alpha-amide while the gamma-ester is selectively substituted in the D-enantiomer. This enzymatic reaction also shows enantioselectivity when a chiral amine is used as nucleophile.
Regioselective lipase-catalysed γ-monoamidation of d-glutamic acid diesters: effect of the N-protecting group
N-Blocked-D-glutamic acid diethylesters are gamma-regioselectively amidated in a reaction catalysed by Candida antarctica lipase B, carried out in an anhydrous organic solvent. The ratio of gamma:alpha-monoamides, as a measure of regioselectivity, depends on the N-protecting group present in the substrate. In the examples reported in this work, we have found that gamma:alpha ranges from about 4 (N-group = Cbz) to 35 (N-group = isobutyryl). No diamides were detected. (C) 2000 Elsevier Science Ltd. All rights reserved.
Enzymatic and solid-phase synthesis of new donepezil-based L- and d-glutamic acid derivatives and their pharmacological evaluation in models related to Alzheimer's disease and cerebral ischemia
作者:Leticia Monjas、Mariana P. Arce、Rafael León、Javier Egea、Concepción Pérez、Mercedes Villarroya、Manuela G. López、Carmen Gil、Santiago Conde、María Isabel Rodríguez-Franco
DOI:10.1016/j.ejmech.2017.02.034
日期:2017.4
Glu enantiomer and the nature of the lipase. An efficient solid-phase route has been used to produce new donepezil-based L- and D-Glu derivatives, resulting in good yield. At micromolar concentrations, the new compounds inhibited human cholinesterases and protected neurons against toxic insults related to Alzheimer's disease and cerebral ischemia. The CNS-permeable compounds N-Cbz-L-Glu(OEt)-[NH-2-(