15207-29-1

Upstream product

• 37963-39-6 (S)-1-((R)-2-{(S)-2-[(S)-5-Benzyloxycarbonylamino-2-((S)-2-tert-butoxycarbonylamino-3-methyl-butyrylamino)-pentanoylamino]-4-methyl-pentanoylamino}-3-phenyl-propionyl)-pyrrolidine-2-carboxylic acid 2,5-dioxo-pyrrolidin-1-yl ester 
• 39606-38-7 H-Val-Orn(Z)-Leu-D-Phe-Pro-Val-Orn(Z)-Leu-D-Phe-Pro-OH 
• 917501-49-6 Boc-D-Phe-Pro-Val-Orn(Z)-OH 

Downstream Products

• 15207-30-4 cyclo-(-Val-Orn-Leu-D-Phe-Pro-)2*2HCl 
• 113-73-5 Gramicidin S 
• 133367-07-4 C₈₀H₁₁₂N₁₂O₁₄ 

Relevant academic research and scientific papers

Spectroscopic characterization of an assembled pair of free-base and zinc porphyrins linked by the cyclic β-sheet peptide Gramicidin S

A pair of porphyrins was linked to the Orn side chains of Gramicidin S [cyclo(-D-Phe-Pro-Val-Orn-Leu-)2] and its derivatives via the amide bonds; the assorted porphyrins were characterized by various spectroscopic methods. The high-field shifts of the porphyrin signals in the 1H NMR spectrum and the exciton-coupled Cotton effects in the CD spectrum of cyclo[-D-Phe-Pro-Val-Orn(Por)-Leu-]2 are both intense compared to those of cyclo[-D-Phe-Pro-Val-Dab(Por)-Leu-]2 or cyclo[-D-Phe-Pro- Val-Lys(Por)-Leu-]2 (Dab, diaminobutyric acid; Por, the side-chain linked porphyrin). Some 1H NMR signals of the tolyl protons of the porphyrins coalesce at 353 K in CD2Cl2, which reveals dynamic processes of the porphyrins. The intensities of the Cotton effect are: Gramicidin S with a pair of free-base porphyrins ≈ Gramicidin S with a free-base porphyrin and a zinc porphyrin 1H NMR, UV-vis, CD and fluorescence spectra show that the solvent substantially influences the assembly of the porphyrins. These spectroscopic studies suggest that the strength of the intramolecular interactions between a pair of porphyrins is in the order of toluene > CH2Cl2 > DMF.

Biomimetic formation of gramicidin S by dimerization-cyclization of pentapeptide precursor on solid support

The biomimetic formation of gramicidin S, cyclo(-d-Phe-Pro-Val-Orn-Leu-)2, by the dimerization and cyclization of pentapeptide precursor without the protection of δ-amino group of the Orn residue was examined on a solid support. The cyclization of H-d-Phe-Pro-Val-Orn-Leu-oxime on a resin with an oxime group of 0.62 mmol/g in 1,4-dioxane directly gave gramicidin S in a 50% yield. The dimerization-cyclization mode on the solid support was similar to that of the biosynthesis of gramicidin S on an enzyme.

Cyclization of Penta- and Hexapeptide Active Esters Related to Gramicidin S and Gratisin

Four pentapeptide N-hydroxysuccinimide esters related to gramicidin S were allowed to cyclize in pyridine.The peptides with a L-Phe residue preceding Pro tend to form various cyclic polimers,

ONE-POT CYCLIZATION OF A PEPTIDE BY THE USE OF (5-NITROPYRIDYL)DIPHENYL PHOSPHINATE: THE SYNTHESIS OF CYCLIC DECAPEPTIDE GRAMICIDIN S

One-pot synthesis of gramicidin S, cyclic decapeptide, was successfully achieved by treatment of the corresponding linear decapeptide with (5-nitropyridyl)diphenyl phosphinate, a new condensing reagent, in pyridine.Similarly, the phosphinic ester can be successfully employed in the Young test as well as syntheses of dipeptides.

FACILE SYNTHESIS OF GRAMICIDIN S VIA CYCLIZATION OF A LINEAR PENTAPEPTIDE

Azide and N-hydroxysuccinimide ester of five pentapeptides related to gramicidin S (cyclic decapeptide) were cyclized to determine the ratio of dimer to monomer in the cyclization product, the pentapeptide dervative with D-Phe as C-terminus giving the dimer in good yield.