55790-24-4

Upstream product

• 7685-65-6 N-(2-nitrophenylsulfenyl)-alanine 
• 2491-20-5 L-alanine methyl ester hydrochloride 
• 7675-46-9 2-nitrophenylsulphenyl-L-alanine dicyclohexylammonium salt 

Downstream Products

• 55790-27-7 (S)-N-((S)-1-Carbamoyl-ethyl)-2-(2-nitro-phenylsulfanylamino)-propionamide 
• 55790-29-9 (S)-N-((S)-Cyano-methyl-methyl)-2-(2-nitro-phenylsulfanylamino)-propionamide 

Relevant academic research and scientific papers

N-TERMINAL SUBSTITUENT AND SIDE-CHAIN INFLUENCES ON THE CHEMICAL SHIFTS OF PROTONS IN MODEL DIPEPTIDE SYSTEMS

(1)H Chemical shift values of ester methyls in model dipeptide esters have been shown to be sensitive to (a) the nature and configuration of the constituent amino acids and (b) the spatial distance between the N-terminal aryl group and the ester protons.C

p-Nitroanilides of 3-carboxypropionyl-peptides. Their cleavage by elastase, trypsin, and chymotrypsin.

Fourteen 3-carboxypropionyl-tripeptide-p-nitroanilides of the general formula 3-carboxypropionyl-alanyl-alanyl-Y-p-nitroanilide (Y = glycine, norvaline, S-methylcysteine, valine, norleucine, S-ethylcysteine, methionine, leucine, isoleucine, phenylalanine, tyrosine, S-benzylcysteine, Calpha-phenylglycine, and proline) were synthesized and their cleavage by elastase, trypsin, and chymotrypsin (Km, kcat and kcat/Km) was determined. The significance of amino acid residues in the position of Y was evaluated firstly with respect to their structure (topographically), and secondly with respect to their free energy (thermodynamically). The alanine residue substrate was cleaved best by elastase, the phenylalanine substrate by chymotrypsin. Trypsin cleaved two substrates only, that is those containing a phenylalanine and a tyrosine residue. The optimum length of the elastolytic substrates was studied in a series of N-3-carboxypropionyl-(Ala)n-p-nitroanilides (n = 1, 2, 3, 4, 5), N-3-carboxypropionyl-(Gly)n-p-nitroanilides (n = 1, 2, 3), and in p-nitroanilides of fatty acids with two to seven carbon atoms. Elastase cleaved tri, tetra, and pentapeptides of alanine. p-Nitroanilides of the glycine series, as well as p-nitroanilides of fatty acids were not cleaved. 3-Carboxypropionyl-tetra-alanine-p-nitroanilide was the most suitable substrate so far found for elastase cleavage; it is not cleaved by trypsin nor chymotrypsin. The optimum distance between Y and the terminal anionic carboxyl residue was found to be 1.8 nm in elastolytic substrates.