Cleavage of esters under nearly neutral conditions at high pressure. Chemo- and regioselective hydrolysis in organic solvents
摘要:
Hydrolysis of esters proceeded at room temperature under high pressures in the presence of iPr2NEt or N-methylmorpholine using CH3CN-H2O (60:1) as the solvent. This very mild procedure enables the smooth hydrolysis of biologically important compounds such as amino esters, aliphatic unsaturated fatty esters, and beta-hydroxy esters; no racemization, no isomerization, and no side reactions take place.
DOI:
10.1021/jo00020a001
作为产物:
描述:
苄氧羰基-L-丙氨酸 在
Bn 作用下,
以
四氢呋喃 为溶剂,
反应 20.0h,
以gave 16 as a clear oil, 1.07 g, 92%的产率得到Z-L-Ala benzyl ester
参考文献:
名称:
Highly reactive, water soluble carbodiimides, intermediates and
Simple and mild esterification of N-protected amino acids with nearly equimolar amounts of alcohols using 1-tert-butoxy-2-tert-butoxycarbonyl-1,2-dihydroisoquinoline
A very mild, one-step esterification using nearly equimolar amounts of N-protectedaminoacids and alcohols, in conjunction with 1-tert-butoxy-2-tert-butoxycarbonyl-1,2-dihydroisoquinoline (BBDI) as a novel condensing reagent is described.
A novel 1-tert-butoxy-2-tert-butoxycarbonyl-1,2-dihydroisoquinoline (BBDI)-catalyzed esterification of N-protected amino acids with nearly equimolar amounts of alcohols in the presence of Boc2O
作者:Yukako Saito、Tomokazu Watanabe、Hiroki Takahata
DOI:10.1016/j.tetlet.2006.02.149
日期:2006.5
A very mild, BBDI-catalyzed esterification using approximately equimolar amounts of N-protectedaminoacids and alcohols, in junction with Boc2O is described.
描述了使用约等摩尔量的N-保护的氨基酸和醇与Boc 2 O连接的非常温和的BBDI催化的酯化反应。
<i>O</i>-Benzylation of Carboxylic Acids Using 2,4,6-Tris(benzyloxy)-1,3,5-triazine (TriBOT) under Acidic or Thermal Conditions
esters from carboxylicacidsusing the O-benzylating reagent 2,4,6-tris(benzyloxy)-1,3,5-triazine (TriBOT) have been developed. The reactions were conducted either in the presence of a catalytic amount of TfOH at room temperature (acidicconditions) or in the absence of TfOH at 180–230 °C (thermalconditions). Interestingly, the O-benzylation of hydroxy carboxylicacidsunder the two conditions afforded
Broadening of the substrate tolerance of α-chymotrypsin by using the carbamoylmethyl ester as an acyl donor in kinetically controlled peptide synthesis
In the kinetically controlled approach of peptide synthesis mediated by α-chymotrypsin, the broadening of the protease’s substrate tolerance is achieved by switching the acyldonor from the conventional methyl ester to the carbamoylmethyl ester. Thus, as a typical example, the extremely low coupling efficiency obtained by employing the methyl ester of an inherently poor amino acid substrate, Ala, is
作者:José G. Hernández、Karen J. Ardila-Fierro、Deborah Crawford、Stuart L. James、Carsten Bolm
DOI:10.1039/c7gc00615b
日期:——
Mechanochemical chemoenzymatic peptide and amidebondformation catalysed by papain was studied by ball milling. Despite the high-energy mixing experienced inside the ball mill, the biocatalyst proved stable and highly efficient to catalyse the formation of α,α- and α,β-dipeptides. This strategy was further extended to the enzymatic acylation of amines by milling, and to the mechanosynthesis of a derivative