177895-44-2

Upstream product

• 177895-42-0 (2-{(S)-3-(4-Hydroxy-phenyl)-2-[((3aS,5aR,8aR,8bS)-2,2,7,7-tetramethyl-tetrahydro-bis[1,3]dioxolo[4,5-b;4',5'-d]pyran-3a-ylmethyl)-amino]-propionylamino}-acetylamino)-acetic acid 
• 173966-40-0 (S)-3-(4-Hydroxy-phenyl)-2-[((3aS,5aR,8aR,8bS)-2,2,7,7-tetramethyl-tetrahydro-bis[1,3]dioxolo[4,5-b;4',5'-d]pyran-3a-ylmethyl)-amino]-propionic acid 
• 60-18-4 L-tyrosine 
• 32786-02-0 2,3:4,5-bis-O-(isopropylidene)-D-fructopyranose aldehyde 
• 68835-84-7 L-phenylalanyl-L-leucine methyl ester trifluoroacetate 

Relevant academic research and scientific papers

Synthesis and 13C NMR investigation of novel Amadori compounds (1-amino-1-deoxy-D-fructose derivatives) related to the opioid peptide, leucine-enkephalin

The N-(1-deoxy-D-fructos-1-yl) derivatives (Amadori compounds) of the endogenous opioid pentapeptide, leucine-enkephalin (11), leucine-enkephalin methyl ester (12) and of structurally related peptides (9, 10) are synthesized. The equilibrium compositions of the prepared Amadori compounds 9-12 in D 2O and [2H6]DMSO are determined using 13C NMR spectroscopy. In water, the β-pyranose, α-furanose and β-furanose forms are detected, the β-pyranose tautomer being the most abundant at equilibrium (67-75%). The α-pyranose form and open-chain keto form are not detected. In dimethyl sulfoxide, the equilibrium compositions of 9-12 are markedly shifted towards a higher proportion of furanose forms, amounting to two-thirds of the mixture. In addition to the α- and β-furanoses and β-pyranose tautomers, DMSO solutions of compounds 9-12 contain at equilibrium a relatively high proportion of the acyclic hydrate (gem-diol) form (ca. 10%).