61131-30-4

Upstream product

• 61196-05-2 Boc-Tyr(Bzl)-Gly-Gly-Phe-OMe 
• 10466-61-2 (2S)-amino-4-methylpentanamide hydrochloride 
• 252846-44-9 Boc-L-Tyr(Bzl)-Gly-Gly-L-Phe-O-carbamoylmethyl 
• 63-91-2 L-phenylalanine 
• 61131-29-1 N-glycyl>-L-3-phenylalanine methyl ester hydrochloride 
• 7524-50-7 methyl (2S)-2-amino-3-phenylpropanoate hydrochloride 
• 63631-32-3 (S)-methyl 12-benzyl-2,2-dimethyl-4,7,10-trioxo-3-oxa-5,8,11-triazatridecan-13-oate 

Downstream Products

• 77511-32-1 5>-enkephalin 
• 58822-25-6 Leu-enkephalin 
• 64963-27-5 N-tert-butyloxycarbonyl-L-tyrosyl-glycyl-glycyl-L-phenylalanyl-L-leucine 
• 126028-16-8 Boc-L-Tyr-Gly-Gly-L-Phe-OCam 
• 64848-07-3 Boc-L-Tyr-Gly-Gly-L-Phe 
• 252846-44-9 Boc-L-Tyr(Bzl)-Gly-Gly-L-Phe-O-carbamoylmethyl 

Relevant academic research and scientific papers

An Effective Water-Free Aprotic System for Dissolving Free Amino Acids

An effective water-free system was proposed for dissolution and subsequent use in peptide synthesis of free amino acids and their derivatives. It consists of dimethylformamide, a tertiary base, and inorganic additives. Neutral salts (CF3COONa, Ba(ClO4)2, Ca(ClO4)2, NaClO4, BaI2, or Ca(NO3)2) serve as the inorganic additives that increase the solubility of free amino acids in dimethylformamide and provide true 0.2-3 M amino acid solutions. Triethylamine and N-methylmorpholine are most suitable as the tertiary bases. This system was used in reactions with acylating agents: Boc2O, ZOSu, FmocOSu, and activated derivatives of Nα-protected amino acids or peptides. The corresponding amino acid derivatives or Nα-protected di-, tri-, and tetrapeptides were obtained in yields of 80-99 percent at the reaction times of 30-240 min.

Superiority of the carbamoylmethyl ester as an acyl donor for the protease-catalyzed kinetically controlled peptide synthesis in organic media: Application to segment condensations

The superiority of the carbamoylmethyl ester as an acyl donor for the α-chymotrypsin-catalyzed kinetically controlled peptide synthesis was demonstrated in several segment condensations carried out in organic media with low water content. Then this approach was successfully applied to the construction of the Leuenkephalin sequence via the 4 + 1 segment condensation.

PEPTIDE SYNTHESIS BY USING PHENYLPHOSPHONIC ESTER AS A COUPLING REAGENT

Synthesis of peptides containing various functions was efficiently accomplished by treatment of the tetrabutylammonium salts of N-protected amino acids (or peptides) with amino acid esters in the presence of bis(o- or p-nitrophenyl) phenylphosphonate.Synthesis of leucine-enkephalin was successfully achieved by the above method employing a (3+2) or (4+1) fragment coupling approach.