80870-40-2

Upstream product

• 116912-20-0 N-(Phenylacetyl)-L-phenylalanyl-L-alanin-tert-butylester 
• 21691-50-9 Ala-OtBu 
• 63-91-2 L-phenylalanine 
• 16503-49-4 (E)-methyl 2-(hydroxyimino)-3-phenylpropanoate 
• 13404-22-3 tert-butyl L-alaninate hydrochloride 
• 738-75-0 (S)-3-phenyl-2-phenylacetylamino-propionic acid 
• 312933-66-7 N-(2,3,4,6-Tetra-O-acetyl-β-D-galactopyranosyloxycarbonyl)-L-phenylalanyl-L-alanine tert-butyl ester 
• 1161-13-3 N-Cbz-L-Phe 
• 33033-71-5 (S)-tert-butyl 2-((S)-2-(((benzyloxy)carbonyl)amino)-3-phenylpropanamido)propanoate 
• 312933-73-6 N-(β-D-Galactopyranosyloxycarbonyl)-L-phenylalanyl-L-alanine tert-butyl ester 

Downstream Products

• 1106947-20-9 Fmoc-Ser(tBu)-Phe-Ala-OtBu 
• 481054-29-9 N-acetylglycyl-L-leucyl-3-chloro-L-alanyl-L-phenylalanyl-L-alanine tert-butyl ester 
• 481054-30-2 N-acetylglycyl-L-leucyl-3-chloro-L-alanyl-L-phenylalanyl-L-alanine 
• 481054-28-8 N-(benzyloxycarbonyl)-3-chloro-L-alanyl-L-phenylalanyl-L-alanine tert-butyl ester 

Relevant academic research and scientific papers

Catalytic Peptide Synthesis: Amidation of N-Hydroxyimino Esters

A catalytic method for the formation of amide bonds was developed in which the amidation of N-hydroxyimino esters with a broad range of amino acid tert-butyl esters is promoted by a niobium catalyst in the absence of solvent. Contrary to the predominant protocol based on reagent control commonly applied to amidation reactions, this study provides insight into an approach based on substrate control. This system affords the corresponding amides in high yields in addition to being both highly atom efficient and racemization-free. An advantage of this system is shown in that the Lewis acid catalysis proceeds chemoselectively in the presence of nonactivated esters. Furthermore, the resulting amides are easily transformed into their corresponding di- and tripeptides with high diastereoselectivities under simple hydrogenation conditions.

Design, synthesis, and biological evaluation of beauveriolide analogues bearing photoreactive amino acids

Beauveriolides I and III, which are naturally occurring cyclodepsipeptides, have been reported to bind to sterol O-acyltransferase (SOAT), inhibiting its ability to synthesize cholesteryl esters. To facilitate an analysis of the binding site(s) of these c

Synthesis of Silacyclic Dipeptides: Peptide Elongation at Both N-And C-Termini of Dipeptide

A new type of peptide bond formation utilizing silacyclic amino acids or peptides is described. This work has the following advantages: (1) imidazolylsilane is a highly fascinating coupling reagent for dipeptide synthesis from N-,C-Terminal unprotected am

Peptide Bond Formation of Amino Acids by Transient Masking with Silylating Reagents

A one-pot peptide bond-forming reaction has been developed using unprotected amino acids and peptides. Two different silylating reagents, HSi[OCH(CF3)2]3 and MTBSTFA, are instrumental for the successful implementation of this approach, being used for the activation and transient masking of unprotected amino acids and peptides at C-termini and N-termini, respectively. Furthermore, CsF and imidazole are used as catalysts, activating HSi[OCH(CF3)2]3 and also accelerating chemoselective silylation. This method is versatile as it tolerates side chains that bear a range of functional groups, while providing up to >99% yields of corresponding peptides without any racemization or polymerization.

METHOD FOR PRODUCING AMIDE COMPOUND

Provided is a novel method for producing amide compounds at high stereochemical selectivities. The method according to the present invention for producing amide compounds is provided with an amidation step for reacting, in the presence of a catalyst compr

Stereocontrolled [11C]Alkylation of N-Terminal Glycine Schiff Bases To Obtain Dipeptides

The use of various quaternary ammonium salts as chiral phase-transfer catalysts allowed effective and stereoselective radiochemical [11C]alkylation to obtain functionalized dipeptides. We herein report a broadly applicable procedure for the asymmetric [11C]alkylation of dipeptides to give labeled N-terminal peptides by using different [11C]alkyl halides. Contended stereoselectivities of the reactions were observed by using 11C-labeled alkyl halides, [11C]methyl iodide and [11C]benzyl iodide, and diastereomeric ratios with different specialized catalysts of 95:5 and 90:10 were achieved, respectively. Accordingly, the straightforward synthesis of enantioenriched compounds should play a vital role in peptide-based radiopharmaceutical development and positron emission tomography imaging.

METHOD FOR SELECTIVE REMOVAL OF DIBENZOFULVENE DERIVATIVE

A reaction mixture containing dibenzofulvene and/or a dibenzofulvene amine adduct, which is obtained by reacting an amino acid compound protected with an Fmoc group with an amine for deprotection, is stirred and partitioned in a hydrocarbon solvent having

Dehydroalanine-based inhibition of a peptide epimerase from spider venom.

Ribosomally produced peptides that contain D-amino acids have been isolated from a number of vertebrate and invertebrate sources. In each case, the D-amino acids are introduced by a posttranslational modification of a parent peptide containing only amino acids of the L-configuration. The only known enzyme to catalyze such a reaction is the peptide epimerase (also known as peptide isomerase) from the venom of the funnel web spider, Agelenopsis aperta. This enzyme interconverts two 48-amino-acid-long peptide toxins that differ only by the stereochemistry at a single serine residue. In this paper we report the synthesis and testing of two pentapeptide analogues that contain modified amino acids at the site normally occupied by the substrate serine residue. When the L-chloroalanine-containing peptide 3 was incubated with the epimerase it was converted into the dehydroalanine-containing peptide 4 via an elimination of HCl. The dehydroalanine peptide 4 was independently synthesized and found to act as a potent inhibitor of the epimerase (IC50 = 0.5 microM). These results support a direct deprotonation/reprotonation mechanism in which a carbanionic intermediate is formed. The observed inhibition by 4 can be attributed to the sp(2)-hybridization of the alpha-carbon in the dehydroalanine unit that mimics the planar geometry of the anionic intermediate.

Enzyme-labile protecting groups in peptide synthesis: Development of glucose- and galactose-derived urethanes

The development of the tetra-O-acetyl-D-glucopyranosyloxycarbonyl (AGlOC) and tetra-O-acetyl-β-D-galactopyranosyloxycarbonyl (AGalOC) protecting groups, which are fully enzyme-labile, carbohydrate-derived urethanes, is described. The protected amino acids were easily synthesized and subsequently converted into a series of model dipeptides through classical peptide couplings. Cleavage of an α/β-anomeric mixture of a model AGlOC dipeptide was achieved with a 'one-pot' procedure in good yield. To gain a better understanding of the enzymatic deprotection reaction, the AGalOC group was removed formation (lipase catalyzed deacetylation, followed by β-galactosidase catalyzed glycosidic bond fragmentation). Under these very mild reaction conditions (aq. buffer pH7.0, 37°C), the desired N-terminal, unprotected dipeptide conjugates were obtained. The methodology was further utilized for the synthesis of an advanced tetrapeptide model system.

The tetrabenzylglucosyloxycarbonyl(BGloc)-group-A carbohydrate-derived enzyme-labile urethane protecting group

The development of the tetrabenzylglucosyloxycarbonyl (BGloc)- protecting group as an enzymatically removable urethane protecting function for peptide synthesis is described. BGloc-protected amino acids are readily synthesized by conversion of amino acid allyl esters into the respective isocyanates, subsequent treatment with 2,3,4,6-tetrabenzylglucose and C- terminal allyl ester cleavage. From BGloc masked dipeptide esters, which are accessible by standard methods of peptide chemistry, the N-terminal urethane is selectively cleaved off in high yield via removal of the benzyl ethers by hydrogenation followed by hydrolysis of the urethane by means of α- and β- glucosidase under very mild reaction conditions.