54793-80-5

Upstream product

• 23631-72-3 N-carbobenzoxy-L-prolyl-L-phenylalanine methyl ester 
• 57177-79-4 (S)-tert-butyl 2-(((S)-1-methoxy-1-oxo-3-phenylpropan-2-yl)carbamoyl)pyrrolidine-1-carboxylate 
• 7524-50-7 methyl (2S)-2-amino-3-phenylpropanoate hydrochloride 
• 15761-39-4 1-(tert-butoxycarbonyl)-L-proline 
• 147-85-3 L-proline 
• 105414-01-5 Cbz-L-Pro-OCO₂-i-Bu 
• 2577-90-4 methyl (2S)-2-amino-3-phenylpropanoate 
• 63-91-2 L-phenylalanine 
• 1148-11-4 N-Benzyloxycarbonyl-L-proline 

Downstream Products

• 3705-26-8 L-Phenylalanyl-L-prolin-lactam 
• 591208-34-3 (S,S)-N-(4-dimethoxymethyl-benzoyl)proline-phenylalanine methyl ester 
• 591208-35-4 (S,S)-N-(3-dimethoxymethyl-benzoyl)proline-phenylalanine methyl ester 
• 937172-16-2 C₂₆H₃₄N₄O₇ 
• 919790-13-9 Boc-Gly-Gly-Pro-Phe-OMe 
• 1000591-14-9 Boc-Gly-Gly-Pro-Phe-OH 
• 919790-14-0 Boc-Gly-Gly-Pro-Phe-Pro-Gly-OMe 
• 1000591-21-8 Boc-Gly-Gly-Pro-Phe-Pro-Gly-OH 
• 919790-15-1 Boc-Gly-Gly-Pro-Phe-Pro-Gly-Tyr-OMe 
• 919790-20-8 Boc-Gly-Gly-Pro-Phe-Pro-Gly-Tyr-O-pnp 
• 129398-84-1 (S)-methyl 2-((S)-1-formylpyrrolidine-2-carbonylamino)-3-phenylpropanoate 
• 1363899-10-8 C₃₁H₄₁N₃O₇Se 
• 1363899-12-0 C₃₁H₄₁N₃O₇S 
• 1363899-21-1 C₄₆H₆₄N₆O₁₂Se₂ 

Relevant academic research and scientific papers

Total syntheses of (?)-emestrin H and (?)-asteroxepin

First total syntheses of (?)-emestrin H and (?)-asteroxepin are described. To find the appropriate protecting group on the amide nitrogen of the diketopiperazine core, we conducted model studies using a simple diketopiperazine derivative. As a result, allyloxymethyl (Allom) group was the most suitable protecting group, which tolerated Nicolaou's sulfenylation conditions, and was easily cleavable under the mild conditions using Pd(PPh3)4 and N,N-dimethylbarbituric acid leaving methylthioethers intact. The general utility of Allom group for protection of amides was studied using simple substrates. Finally, the effectiveness of Allom group was proved by the accomplishment of the first total synthesis of (?)-emestrin H. Allom group was robust enough during installation of two methylthioethers to the diketopiperazine core and easily removed at the final step. The first total synthesis of (?)-asteroxepin was also completed by acylation of (?)-emestrin H.

Engineered Substrate for Cyclooxygenase-2: A Pentapeptide Isoconformational to Arachidonic Acid for Managing Inflammation

Beyond the conventional mode of working of anti-inflammatory agents through enzyme inhibition, herein, COX-2 was provided with an alternate substrate. A proline-centered pentapeptide isoconformational to arachidonic acid, which exhibited appreciable selectivity for COX-2, overcoming acetic acid- and formalin-induced pain in rats to almost 80%, was treated as a substrate by the enzyme. Remarkably, COX-2 metabolized the pentapeptide into small fragments consisting mainly of di- and tripeptides that ensured the safe breakdown of the peptide under in vivo conditions. The kinetic parameter Kcat/Km for COX-2-mediated metabolism of the peptide (6.3 × 105 M-1 s-1) was quite similar to 9.5 × 105 M-1 s-1 for arachidonic acid. Evidenced by the molecular dynamic studies and the use of Y385F COX-2, it was observed that the breakage of the pentapeptide has probably been taken place through H-bond activation of the peptide bond by the side chains of Y385 and S530.

Evaluation of two cyclic di-peptides as inhibitors of CCL2 induced chemotaxis

Monocyte chemoattractant protein (CCL2) plays a major role in the recruitment of monocytes during inflammation. In this study we analysed properties of synthetic CCL2 inhibitors in inhibiting CCL2 mediated monocyte migration. Using trans-endothelial chemotaxis assays compounds C1 and C5 were found to significantly reduce CCL2 mediated migration. Flow based adhesion assays showed reduction in adhesion to VCAM-1 in the presence of 10 nM CCL2 and 50 μM C5 (p 0.05). Further studies with these compounds can aid in their development as anti-inflammatory therapies. The Royal Society of Chemistry 2013.

Antioxidant activity of peptide-based angiotensin converting enzyme inhibitors

Angiotensin converting enzyme (ACE) inhibitors are important for the treatment of hypertension as they can decrease the formation of vasopressor hormone angiotensin II (Ang II) and elevate the levels of vasodilating hormone bradykinin. It is observed that bradykinin contains a Ser-Pro-Phe motif near the site of hydrolysis. The selenium analogues of captopril represent a novel class of ACE inhibitors as they also exhibit significant antioxidant activity. In this study, several di- and tripeptides containing selenocysteine and cysteine residues at the N-terminal were synthesized. Hydrolysis of angiotensin I (Ang I) to Ang II by ACE was studied in the presence of these peptides. It is observed that the introduction of l-Phe to Sec-Pro and Cys-Pro peptides significantly increases the ACE inhibitory activity. On the other hand, the introduction of l-Val or l-Ala decreases the inhibitory potency of the parent compounds. The presence of an l-Pro moiety in captopril analogues appears to be important for ACE inhibition as the replacement of l-Pro by l-piperidine 2-carboxylic acid decreases the ACE inhibition. The synthetic peptides were also tested for their ability to scavenge peroxynitrite (PN) and to exhibit glutathione peroxidase (GPx)-like activity. All the selenium-containing peptides exhibited good PN-scavenging and GPx activities. The Royal Society of Chemistry 2012.

Solvent-free asymmetric aldol reaction organocatalyzed by (S)-proline-containing thiodipeptides under ball-milling conditions

An efficient, solvent-free ball-milling protocol for the asymmetric aldol reaction between cyclohexanone and cyclopentanone with various aromatic aldehydes using a novel series of (S)-proline-containing dipeptides and thiodipeptides 1a-f as organocatalysts is reported. In general, (S)-proline-containing thiodipeptides proved to be better organocatalysts relative to their analogous amides. In particular, thiodipeptide (S,S)-1d catalyzed the stereoselective formation of the expected aldol products with excellent diastereo- and enantioselectivity (up to 98:2 anti/syn dr and up to 96% ee). This observation may be ascribed to the increased N-H acidity of the thioamide segment that leads to stronger H-bonding interaction with the aldehyde carbonyl at the transition state and thus higher stereoinduction. Furthermore, thiodipeptide 1f proved to be an efficient organocatalyst for the aldol reaction of acetone with isatin and isatin derivatives (ee 56-86%).

Asymmetric aldol reaction organocatalyzed by (S)-proline-containing dipeptides: Improved stereoinduction under solvent-free conditions

The organocatalytic activity of the methyl ester of (S)-proline-(S)- phenylalanine, (S,S)-2, in the asymmetric aldol reaction between cyclohexanone and acetone with various aromatic aldehydes under solvent-free conditions in a ball mill has been evaluated. α,α-Dipeptide (S,S)-2 catalyzed the stereoselective formation of the expected aldol products, with higher diastereo-and enantioselectivity relative to similar reactions in solution, up to 91:9 anti:syn diastereomeric ratio and up to 95% enantiomeric excess.(Figure Presented)

Efficient ball-mill procedure in the 'green' asymmetric aldol reaction organocatalyzed by (S)-proline-containing dipeptides in the presence of water

The organocatalytic activity of (S)-proline-based dipeptides 1a-c has been evaluated in the asymmetric aldol reaction between representative ketones with various aromatic aldehydes under solvent-free conditions in a ball mill. In particular, the methyl ester of (S)-proline-(S)-tryptophan, (S,S)-1c, proved to be an efficient organocatalyst, and the aldol reaction proceeded with good chemical yields and excellent diastereo- and enantioselectivity (up to 98:2 anti/syn dr and up to 98% ee), in the presence of water, and 5 mol % of benzoic acid as additive.

Synthesis and catalytic activities of (S)-1-formylpyrrolidine-2-carboxylic acid derivatives for the enantioselective reductions of both a ketone and a ketimine

A series of (S)-1-formylpyrrolidine-2-carboxylic acid derivatives (6a-t) have been synthesised and examined as chiral organocatalysts in the asymmetric reduction of both ketone 2 and ketimine 3. These organic activators afforded good to moderate enantiose

Synthesis, characterization and biological evaluation of cyclic peptides: Viscumamide, yunnanin A and evolidine

Three biologically active cyclic peptides, viscumamide, yunnanin A and evolidine were synthesized and the structures were established on the basis of analytical, IR, NMR and mass spectral data. These newly synthesized cyclic peptides were evaluated for an

Small peptides catalyze highly enantioselective direct aldol reactions of aldehydes with hydroxyacetone: Unprecedented regiocontrol in aqueous media

L-Proline-based small peptides have been developed as efficient catalysts for the asymmetric direct aldol reactions of hydroxyacetone with aldehydes. Chiral 1,4-diols 7, which are disfavored products in similar aldol reactions catalyzed by either aldolases or t-proline, were obtained in high yields and enantioselectivities of up to 96% ee with peptides 3 and 4 in aqueous media.