4818-07-9

Upstream product

• 2578-84-9 N-benzyloxycarbonyl-L-phenylalanine p-nitrophenyl ester 
• 616-34-2 methoxycarbonylmethylamine 
• 76413-57-5 [(S)-1-Benzyl-2-oxo-2-(2-thioxo-thiazolidin-3-yl)-ethyl]-carbamic acid benzyl ester 
• 1161-13-3 N-Cbz-L-Phe 
• 666177-20-4 N-(5-methyl-1-benzotriazolecarbonyl)glycine methyl ester 
• 3397-32-8 N-(benzyloxycarbonyl)-phenylalanine-N-hydroxysuccinimide ester 
• 84814-41-5 2-Benzyloxycarbonylamino-3-phenyl-propionic acid (2S,3R,4S,5R,6R)-3,4,5-triacetoxy-6-acetoxymethyl-tetrahydro-pyran-2-yl ester 
• 84814-41-5 2-Benzyloxycarbonylamino-3-phenyl-propionic acid (2R,3R,4S,5R,6R)-3,4,5-triacetoxy-6-acetoxymethyl-tetrahydro-pyran-2-yl ester 
• 64-17-5 ethanol 
• 62076-41-9 Cbz-Phe-Gly-Ser-OMe 
• 67-56-1 methanol 
• 17187-05-2 Z-L-phenylalanylglycinamide 
• 91285-91-5 benzyl 2-thioxobenzo[d]oxazol-3(2H)-carboxylate 
• 96452-48-1 benzyl pyridin-2-yl carbonate 

Downstream Products

• 87043-00-3 methyl (S)-(2-(((benzyloxy)carbonyl)amino)-3-phenylpropanethioyl)glycinate 
• 7625-59-4 L-phenylalanylglycine methyl ester hydrochloride 
• 95205-19-9 mononitrosated benzoxycarbonylphenylalanylglycine methyl ester 
• 95205-18-8 dinitrosated benzoxycarbonylphenylalanylglycine methyl ester 
• 5037-75-2 cyclo(Gly-Phe) 
• 131696-95-2 Boc-Glu(OBzl)-Phe-Gly-OMe 
• 131696-97-4 Boc-Thr-Glu-Phe-Gly-OMe 
• 131696-98-5 Boc-Thr-Glu-Phe-Gly-NHNH₂ 
• 131696-96-3 Boc-Thr-Glu(OBzl)-Phe-Gly-OMe 
• 57294-43-6 Cbz-Phe-Gly-OBn 
• 721-90-4 (S)-PheGly 
• 65279-14-3 Benzyloxycarbonyl-L-leucyl-L-phenylalanyl-glycine methyl ester 
• 65559-52-6 L-Leucyl-L-phenylalanyl-glycine methyl ester 

Relevant academic research and scientific papers

Peptide-Chain Elongation Using Unprotected Amino Acids in a Micro-Flow Reactor

Conventional peptide synthesis requires a deprotection step after each amidation step, which decreases synthetic efficiency. Therefore, peptide synthesis using unprotected amino acids is considered an ideal approach. Here, we report peptide chain elongati

Asymmetric Michael addition organocatalyzed by α,β-dipeptides under solvent-free reaction conditions

The application of six novel α,β-dipeptides as chiral organocatalysts in the asymmetric Michael addition reaction between enolizable aldehydes and N-arylmaleimides or nitroolefins is described. With N-arylmaleimides as substrates, the best results were achieved with dipeptide 2 as a catalyst in the presence of aq. NaOH. Whereas dipeptides 4 and 6 in conjunction with 4-dimethylaminopyridine (DMAP) and thiourea as a hydrogen bond donor proved to be highly efficient organocatalytic systems in the enantioselective reaction between isobutyraldehyde and various nitroolefins.

Scandium(III) triflate-promoted serine/threonine-selective peptide bond cleavage

The site-selective cleavage of peptide bonds is an important chemical modification that is useful not only for the structural determination of peptides, but also as an artificial modulator of peptide/protein function and properties. Here we report site-selective hydrolysis of peptide bonds at the Ser and Thr positions with a high conversion yield. This chemical cleavage relies on Sc(iii)-promoted N,O-acyl rearrangement and subsequent hydrolysis. The method is applicable to a broad scope of polypeptides with various functional groups, including a post-translationally modified peptide that is unsuitable for enzymatic hydrolysis. The system was further extended to site-selective cleavage of a native protein, Aβ1-42, which is closely related to the onset of Alzheimer's disease.

One-step C-terminal deprotection and activation of peptides with peptide amidase from stenotrophomonas maltophilia in neat organic solvent

Chemoenzymatic peptide synthesis is a rapidly developing technology for cost effective peptide production on a large scale. As an alternative to the traditional C→N strategy, which employs expensive N-protected building blocks in each step, we have investigated an N→C extension route that is based on activation of a peptide C-terminal amide protecting group to the corresponding methyl ester. We found that this conversion is efficiently catalysed by Stenotrophomonas maltophilia peptide amidase in neat organic media. The system excludes the possibility of internal peptide cleavage as the enzyme lacks intrinsic protease activity. The produced peptide methyl ester was used for peptide chain extension in a kinetically controlled reaction by a thermostable protease.

Recyclable hypervalent iodine(III) reagent iodosodilactone as an efficient coupling reagent for direct esterification, amidation, and peptide coupling

A hypervalent iodine(III) reagent plays a novel role as an efficient coupling reagent to promote the direct condensation between carboxylic acids and alcohols or amines to provide esters, macrocyclic lactones, amides, as well as peptides without racemization. The regeneration of iodosodilactone (1) can also be readily achieved. The intermediate acyloxyphosphonium ion C from the activation of a carboxylic acid is thought to be involved in the present esterification reaction.

N,O-isopropylidenated threonines as tools for peptide cyclization: Application to the synthesis of mahafacyclin B

(Chemical Equation Presented) The influence of a single N,O-isopropylidenated threonine turn-inducer on the cyclization of a linear heptapeptide precursor to mahafacyclin B has been investigated. Incorporation of an N,O-isopropylidenated threonine more th

Influence of solvent viscosity on the rate of hydrolysis of dipeptides by carboxypeptidase Y

The influence of solvent viscosity on the rate of enzymatic hydrolysis of a series of dipeptides (Z-Phe-Gly, Z-Phe-Sar, Z-Phe-Ala, Z-Phe-NMeAla, Z-Phe-Aib and Z-Phe-Pro) by carboxypeptidase Y was investigated. The effect of solvent viscosity on the enzymatic hydrolysis revealed that whereas all Kcat values decreased with viscosity, those of the N-alkyl peptides decreased more than those of the N-H peptides. The kinetic behaviour implies the involvement of conformational changes of the enzyme in terms of the 'induced-fit' process. Copyright

Nickel complexes from α-amino amides as efficient catalysts for the enantioselective Et2Zn addition to benzaldehyde

Ni2+ complexes derived from simple α-amino amides catalyze very efficiently the addition of Et2Zn to benzaldehyde, giving (S)-1-phenylethanol as the major isomer in most cases (94% yield, 97% ee for R=Bn). The nature of the substituent on the amide nitrogen atom seems to play a key role in determining the asymmetric induction observed.

Synthesis and reactions of some azolecarboxylic acid derivatives

Reaction of several azoles with phosgene or triphosgene was studied. Besides benzotriazole (previously described reaction), only indazole, 5-nitroindazole and 5-methylbenzotriazole gave the corresponding 1-azolecarbonyl chlorides 1a-d. Azoles of weak acidity (imidazole, 1,2,3-triazole, 1,2,4-triazole, benzimidazole) could not give stable acyl chlorides, while strong acidic azoles like tetrazole and 4,5,6,7- tetrachlorobenzotriazole did not react at all. Chlorides 1b-d readily reacted with alcohols, amines, amino acids and their esters like the previously described 1-benzotriazolecarboxylic acid chloride (1a), giving 1-azolecarboxylic acid esters (2) or amides (3), N-(1-azolecarbonyl)amino acids (4, 5), their esters (8, 9) or amides (10, 11). However, a significant difference was observed in the reactivity of azole derivatives 2-11 with amines, alcohols and N-protected amino acids or in their stability in acidic and basic aqueous media. Benzotriazole and methylbenzotriazole derivatives were more reactive than indazole or nitroindazole derivatives. The higher reactivity was in correlation with the shift of the IR carbonyl absorption band to higher wave numbers.

Immobilized Aspergillus Oryzae Protease Catalyzed Formation of Peptide Bonds in Organic Solvent

Immobilized Aspergillus oryzae protease (AOP) catalyzed the formation of peptide bonds between N-protected amino acids and amino acid esters or amides in ethyl acetate. The influences of pH and reaction time on the coupling of Boc-L-Tyr and Gly-NH2/