42998-42-5

Upstream product

• 17609-47-1 valine ethyl ester hydrochloride 
• 64-17-5 ethanol 
• 1149-26-4 N-benzyloxycarbonylvaline 
• 1149-26-4 (S)-N-(benzyloxycarbonyl)valine 
• 541-41-3 chloroformic acid ethyl ester 
• 15112-52-4 monoethyl ester of isopropylmalonic acid 
• 100-51-6 benzyl alcohol 

Downstream Products

• 17016-83-0 (4S)-4-isopropyl-1,3-oxazolidin-2-one 
• 2443-71-2 benzyl (S)-(1-hydrazineyl-3-methyl-1-oxobutan-2-yl)carbamate 
• 1449512-59-7 (S)-(N-hydroxy-3-oxobutanoylaminomethyl-2-methylpropyl)carbamic acid benzyl ester 
• 1449512-57-5 (S)-2-benzyloxycarbonylamino-3-methylbutanaldoxime 
• 130258-33-2 C₂₆H₃₅NO₆ 
• 138754-84-4 N-benzyloxycarbonyl-L-valinal 
• 17609-47-1 L-Valine ethyl ester hydrochloride 
• 33280-94-3 C₈H₁₃NO₃ 

Relevant academic research and scientific papers

An Atom-Economic Inverse Solid-Phase Peptide Synthesis Using Bn or BcM Esters of Amino Acids

An atom-economic N-to-C-directed solid-phase peptide synthesis is reported that uses benzyl (Bn) or (benzhydryl-carbamoyl)-methyl (BcM) esters of amino acids as the building blocks, which facilitate efficient hydrazinolysis, convenient conversion to acyl azide, and robust amidation with the next amino acid ester. This method is free of coupling reagents and free of protection on the side-chain OH, CO2H, CONH2, etc., therefore exhibiting a significantly improved atom economy compared to those of BOC- or Fmoc-based C-to-N-directed approaches.

Combinatorial synthesis of 3,5-Dimethylene substituted 1,2,4-Triazoles

Combinatorial cyclizations of imidates and hydrazides with methylene linked R groups, generated from the corresponding nitriles and carboxylic acids, respectively, provided a large library of 3,5-dimethylene substituted 1,2,4- trizoles. 2011 Bentham Science Publishers Ltd.

Papain-catalyzed esterification of N(α)-protected amino acids and dipeptides with ethanol in different organic systems

The papain-catalyzed esterification of N(α)-protected amino acids and dipeptides with ethanol in mostly hydrophobic organic solvent systems containing low amounts of water has been investigated. The influence of various parameters, such as the amount of added water, reaction time, temperature and pH of added buffer, on the yield of ester was studied first on the model substrate Z-Ala. The optimized reaction conditions were then used for esterification of a series of N(α)-protected amino acids and dipeptides.

PAPAIN-ASSISTED RESOLUTION OF NATURAL AND XENOBIOTIC α-AMINO ACIDS

A new and convenient method for the preparation of pure enantiomers of α-amino acids is described.Industrial papain, catalyzes the synthesis of L-Z-amino acid ethyl esters in ethanolic medium, with good yields.These esters are obtained from DL-Z-amino acids with 100percent optical purity.Unreactive D-Z-amino acids are readily isolated from reaction medium.Physical constants of natural and xenobiotic L-Z-amino acid esters and D-Z-amino acids are described.

UTILISATION DES HYDROLASES EN CHIMIE ORGANIQUE: SYNTHESE DE LIAISONS ESTER ET AMIDE CATALYSEE PAR LA PAPAINE INDUSTRIELLE

The use of hydrolases in organic chemistry: synthesis of amide and ester bonds catalyzed by industrial papain.Industrial papain, which is readily available, catalyzed the synthesis of L-Z-alanine ethyl ester (L-ZAEt) in organic medium, under different conditions, with good yields.L-ZAEt was obtained from DL-Z-alanine with 100 percent optical purity.We studied the effects of pH, the solvent/substrate and papain/substrate ratios and the type of organic solvent added, on the L-ZAEt yield.Unreactive D-ZA was also easily isolated from the aqueous phase with good optical purity.This attractive method has been applied to other N-Z-amino acid esters with the same succes.This procedure has been developed for the preparation of peptides using carboxylic or phosphonic substrates.These peptides have anti-bacterial activity. enzymatic catalysis / papain / chymopapain / stereospecific esterification of carboxylic amino acids / dipeptides / phosphonopeptides / anti-bacterial activity

A Simple and Mild Esterification Method for Carboxylic Acids Using Mixed Carboxylic-Carbonic Anhydrides

A simple and mild esterification method using mixed carboxylic-carbonic anhydrides has been developed.Simple aliphatic carboxylic esters are prepared in high yields by the reaction of acids with equimolar amounts of chloroformates (2,2,2-trichloroethyl chloroformate is an exception) and triethylamine in the presence of a catalytic amount of 4-(dimethylamino)pyridine.Although aromatic acids give a mixture of the ester, the acid anhydride, and the carbonate under normal conditions utilized in this study, it is found that increasing the amount of 4-(dimethylamino)pyridine drastically decreases the formation of the acid anhydride and the carbonate, affording a satisfactory yield of the ester.This method reaches a limit with sterically hindered acids and the formation of the acid anhydride and the carbonate is favored.