13171-94-3

Upstream product

• 687-51-4 H-L-Leu-NH₂ 
• 1161-13-3 N-Cbz-L-Phe 
• 4816-89-1 Cbz-Phe-OCH₂CONH₂ 
• 4865-47-8 phenyl ester of N-benzyloxycarbonyl-L-phenylalanine 
• 35909-92-3 N-carbobenzoxy-L-phenylalanine methyl ester 
• 28709-70-8 N-benzyloxycarbonyl-L-phenylalanine ethyl ester 
• 7663-85-6 N-(carbobenzyloxy)phenylalanine cyanomethyl ester 
• 126028-13-5 Z-PheOMem 
• 126028-14-6 2,2,2-trifluoroethyl ((benzyloxy)carbonyl)-L-phenylalaninate 
• 10466-61-2 (2S)-amino-4-methylpentanamide hydrochloride 
• 84969-54-0 H-Leu-NH₂*formate 
• 3850-45-1 Cbz-L-Phe-L-Leu-OMe 
• 146548-58-5 2-chloroethyl N-<(benzyloxy)carbonyl>-L-phenylalaninate 
• 71785-36-9 Z-L-Phe-OCH(CF₃)2 

Downstream Products

• 84969-55-1 Phe-Leu-NH₂*HCOOH 
• 4313-73-9 N-[N-[(phenylmethoxy)carbonyl]-L-phenylalanyl]-L-leucine 
• 38678-59-0 L-Phe-L-Leu-NH₂ 
• 81638-86-0 (S)-2-((S)-2-amino-3-phenylpropanamido)-4-methylpentanamide hydrochloride 
• 69193-15-3 N-(benzyloxycarbonyl)-glycyl-L-phenylalanyl-L-leucine amide 
• 71591-21-4 Z-Tyr-Gly-Gly-Phe-Leu-NH₂ 
• 82948-92-3 [des-tyr¹]-leucine enkephalinamide 
• 84969-56-2 Z-Gly-Gly-L-Phe-L-Leu-NH₂ 
• 71591-20-3 H-Gly-Phe-Leu-NH₂ 
• 65189-64-2 H-Tyr-D-Ala-Gly-Phe-Leu-NH₂ 
• 85574-42-1 Z-Tyr(Z)-(D)Ala-Gly-Phe-Leu-NH₂ 
• 3850-45-1 Cbz-L-Phe-L-Leu-OMe 
• 35909-92-3 N-carbobenzoxy-L-phenylalanine methyl ester 
• 61-90-5 L-leucine 

Relevant academic research and scientific papers

A novel support for enzyme adsorption: Properties and applications of aerogels in low water media

Aerogels, because of their porosity, have a great ability to adsorb water, and this characteristic was exploited to extend the applicability of aerogels for the adsorption and entrapment of hydrolases to be used in organic media. The applicability of aero

High isolated yields in thermodynamically controlled peptide synthesis in toluene catalysed by thermolysin adsorbed on Celite R-640

An innovative immobilisation method that allows peptide synthesis to be performed even at equimolar concentrations, by controlling water activity, is reported.

Mechanoenzymatic peptide and amide bond formation

Mechanochemical chemoenzymatic peptide and amide bond formation 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 of the valuable dipeptide L-alanyl-l-glutamine.

Kinetically controlled peptide synthesis mediated by papain using the carbamoylmethyl ester as an acyl donor

A series of dipeptides were synthesized generally in good yields with carbamoylmethyl (Cam) esters as acyl donors in the presence of a cysteine protease, papain, immobilized on Celite. Several segment condensations were also achieved generally in high yields without danger of racemization and formation of the secondary-hydrolysis product. Moreover, partial sequences of some bioactive peptides were prepared through segment condensations, and aimed-at peptides were obtained generally in high yields without the racemization of C-terminal residues of the carboxyl components. Thus, the superiority of the Cam ester in the kinetically controlled peptide synthesis was once again ascertained in couplings mediated by the cysteine protease as in those catalyzed by the serine proteases reported earlier.

Enzymatic C-terminal amidation of amino acids and peptides

Herein, we describe two versatile and high yielding enzymatic approaches for the conversion of semi-protected amino acid and peptidyl C-terminal α-carboxylic acids into their corresponding amides. In the first approach, the lipase Candida antarctica lipase-B (Cal-B), and in the second approach, the protease Subtilisin A, are used, respectively. We found that by using the ammonium salt of the α-carboxylic acid instead of separate ammonia sources, the enzymatic amidation reactions proceeded much faster without side reactions and gave near to quantitative yields of products.

Fully enzymatic N→C-directed peptide synthesis using C-terminal peptide α-carboxamide to ester interconversion

Chemoenzymatic peptide synthesis is potentially the most cost-efficient technology for the synthesis of short and medium-sized peptides with some important advantages. For instance, stoichiometric amounts of expensive coupling reagents are not required and racemisation does not occur rendering purification easier compared to chemical peptide synthesis. In this paper, a novel interconversion reaction of peptide C-terminal α-carboxamides into primary alkyl esters with alcalase was used to develop a fully enzymatic peptide synthesis strategy. For each elongation step a cost-efficient amino acid carboxamide building block was used followed by the interconversion of the elongated peptide carboxamide to the corresponding primary alkyl ester. These peptide esters are the starting materials for the next enzymatic peptide elongation step. Copyright

α-Chymotrypsin-catalyzed peptide synthesis in frozen aqueous solution using N-protected amino acid carbamoylmethyl esters as acyl donors

A kinetically controlled peptide synthesis catalyzed by α-chymotrypsin was performed in frozen aqueous solution (ice, -24 °C). The yield of the peptide was significantly improved by the use of the carbamoylmethyl (Cam) ester as the acyl donor instead of the conventional ethyl ester. The peptide yield increased up to ca. 90% when N-benzyloxycarbonyl (CBZ)-Phe-OCam and H-Phe-NH2 were used as the acyl donor and nucleophile, respectively. Such an improvement of the peptide yield in ice was also observed in the coupling of other CBZ-amino acid Cam esters as acyl donors. Furthermore, this approach was applied to the synthesis of peptides containing d-amino acids. The peptides such as CBZ-d-Phe-Phe-NH2, CBZ-Phe-d-Phe-NH2 and CBZ-d-Phe-d-Phe-NH2 were also obtained in excellent to moderate yields in ice. A high diastereoselectivity towards the l-l peptide was observed when the racemic amino acid Cam ester was used as the acyl donor in ice.

Reverse proteolysis promoted by in situ generated peptide ester fragments

In this contribution we describe a general synthesis concept for the in situ preparation of protease specific reactants using methyl thioesters as universal precursors. The precursor esters are readily available by standard synthesis procedures and can be

α-chymotrypsin-catalysed segment condensations via the kinetically controlled approach using carbamoylmethyl esters as acyl donors in organic media

The superiority of the carbamoylmethyl ester as an acyl donor for the α-chymotrypsin-catalysed segment condensations via the kinetically controlled approach is demonstrated in several model systems carried out in organic media with low water content. Furthermore, this approach is successfully applied to the construction of the Leu-enkephalin sequence via a 4 + 1 segment coupling.

α-chymotrypsin-catalysed peptide synthesis via the kinetically controlled approach using activated esters as acyl donors in organic solvents with low water content: Incorporation of non-protein amino acids into peptides

The α-chymotrypsin-catalyzed peptide synthesis via the kinetically controlled approach using activated esters as acyl donors in orgnanic solvents with low water content was presented. The methyl esters of N-Z derivatives of racemic non-protein amino acids were chosen as carboxy components. They allowed the peptide-bond formation and optical resolution simultaneously to yield homochiral peptides. This method is useful for the incorporation of non-protein amino acids into peptides.