5654-85-3

Upstream product

• 35446-32-3 (S)-3-((Ξ)-benzylidene)-hexahydro-pyrrolo[1,2-a]pyrazine-1,4-dione 
• 100665-27-8 (5S,6aR,10bR,10cS)-5-Benzyl-10b-hydroxy-hexahydro-8-thia-3a,5a,10a-triaza-cyclopenta[c]fluorene-4,6,10-trione 
• 214849-88-4 (S)-3-[(Z)-benzylidene]hexahydropyrrolo[1,2-a]pyrazine-1,4-dione 
• 54793-80-5 (S)-proline-(S)-phenylalanine methyl ester 
• 15761-39-4 1-(tert-butoxycarbonyl)-L-proline 
• 13734-34-4 N-tert-butoxycarbonyl-L-phenylalanine 
• 77100-17-5 L-phenylalaninyl-L-proline methyl ester hydrochloride 
• 63-91-2 L-phenylalanine 
• 147-85-3 L-proline 
• 35802-19-8 5-benzyl-1-benzyloxycarbonyl-10b-hydroxy-2-methyl-1,8,9,10,10a,10b-hexahydroimidazo<1,2-a>pyrrolo<2,1-c>pyrazine-3,6(2H,5H)-dione 
• 118903-77-8 (R)-5-oxothiomorpholin-3-ylcarbonyl-L-phenylalanyl-L-proline-t-butyl ester 
• 1403821-08-8 (S)-Fmoc-Phe(pNO₂)-Oallyl 
• 95753-55-2 N-α-FMOC-4-nitro-L-phenylalanine 
• 1403821-04-4 C₂₇H₂₆N₂O₄ 

Downstream Products

• 3919-02-6 N-L-prolyl-L-phenylalanine 
• 78452-06-9 [(S)-1-((3S,8aS)-3-Benzyl-1,4-dioxo-hexahydro-pyrrolo[1,2-a]pyrazine-2-carbonyl)-2-methyl-propyl]-carbamic acid benzyl ester 
• 96625-34-2 N--Phe-Pro-Lactam 
• 50868-53-6 N-(d-Lysergyl-L-valyl)-L-phenylalanyl-L-prolin-lactam 
• 78452-05-8 [(S)-1-((3S,8aS)-3-Benzyl-1,4-dioxo-hexahydro-pyrrolo[1,2-a]pyrazine-2-carbonyl)-2-methyl-propyl]-carbamic acid tert-butyl ester 
• 81531-47-7 N--Phe-Pro-Lactam 
• 914771-44-1 (3S,8aS)-3-benzyloctahydropyrrolo[1,2-a]pyrazine 
• 32021-26-4 3-benzylhexahydropyrrolo[1,2-a]pyrazin-1,4-dione 
• 95713-60-3 L-Phe-L-FDAA 
• 147-85-3 L-proline 
• 95713-61-4 L-FDAA-D-Phe 
• 128425-02-5 L-FDAA-L-Pro 
• 673-06-3 D-(R)-phenylalanine 

Relevant academic research and scientific papers

Unambiguous stereochemical assignment of cyclo(Phe-pro), cyclo(leu-pro), and cyclo(val-pro) by electronic circular dichroic spectroscopy

2,5-diketopiperazines (DKPs) are cyclic dipeptides ubiquitously found in nature. In particular, cyclo(Phe-Pro), cyclo(Leu-Pro), and cyclo(Val-Pro) are frequently detected in many microbial cultures. Each of these DKPs has four possible stereoisomers due to the presence of two chirality centers. However, absolute configurations of natural DKPs are often ambiguous due to the lack of a simple, sensitive, and reproducible method for stereochemical assignment. This is an important problem because stereochemistry is a key determinant of biological activity. Here, we report a synthetic DKP library containing all stereoisomers of cyclo(Phe-Pro), cyclo(Leu-Pro), and cyclo(Val-Pro). The library was subjected to spectroscopic characterization using mass spectrometry, NMR, and electronic circular dichroism (ECD). It turned out that ECD can clearly differentiate DKP stereoisomers. Thus, our ECD dataset can serve as a reference for unambiguous stereochemical assignment of cyclo(Phe-Pro), cyclo(Leu-Pro), and cyclo(Val-Pro) samples from natural sources. The DKP library was also subjected to a biological screening using assays for E. coli growth and biofilm formation, which revealed distinct biological effects of cyclo(D-Phe-L-Pro).

Molecular capture and conformational change of diketopiperazines containing proline residues by epigallocatechin-3-O-gallate in water

The addition of an aqueous solution of diketopiperazine cyclo(Pro-Xxx) (Xxx: amino acid residue) to an aqueous solution of (?)-epigallocatechin-3-O-gallate (EGCg) led to precipitation of the complex of EGCg and cyclo(Pro-Xxx). The molecular capture abilities of cyclo(Pro-Xxx) using EGCg were evaluated by the ratio of the amount of cyclo(Pro-Xxx) included in the precipitates of the complex with EGCg to that of the total cyclo(Pro-Xxx) used. Stronger hydrophobicity of the side chain of the amino acid residue of cyclo(Pro-Xxx) led to a higher molecular capture ability. Furthermore, the molecular capture ability decreased when the side chain of the amino acid residue had a hydrophilic hydroxyl group. When diketopiperazine cyclo(Pro-Xxx), excluding cyclo(D-Pro-L-Ala), was taken into the hydrophobic space formed by the three aromatic A, B, and B′ rings of EGCg, and formed a complex, their conformation was maintained in the hydrophobic space. Based on nuclear Overhauser effect (NOE) measurement, the 3-position methyl group of cyclo(D-Pro-L-Ala) in D2O was axial, whereas that of cyclo(L-Pro-L-Ala) was equatorial. When cyclo(D-Pro-L-Ala) was taken into the hydrophobic space of EGCg and formed a 2:2 complex, its 3-position methyl group changed from the axial position to the equatorial position due to steric hindrance by EGCg.

Antidiabetic in vitro and in vivo evaluation of cyclodipeptides isolated from Pseudomonas fluorescens IB-MR-66e

Three cyclodipeptides [cyclo(l-Pro-l-Leu), 1; cyclo(l-Pro-l-Val), 2; and cyclo(l-Pro-l-Phe), 3] were isolated from Pseudomonas fluorescens IB-MR-66e. The structures were established by spectral means and corroborated by synthesis. The antidiabetic potential of compounds 1-3 was explored in vivo, in vitro and in silico. The three peptides showed important inhibitory activity against the α-glucosidase enzyme. Further analysis in vivo using a sucrose tolerance test corroborated that compounds 1 and 3 (1-30 mg kg-1) significantly reduced the postprandial state. Peptide 1 (1-30 mg kg-1) also reduced the postprandial peak after a glucose challenge and exhibited significant hypoglycemia during an insulin tolerance test; thus, its antidiabetic action involved also an improvement of insulin utilization not related to Akt phosphorylation nor to an increment in mitochondrial bioenergetics nor insulin secretion.

Synthesis of 3-Benzylhexahydropyrrolo[1,2-a]pyrazine-1,4-dione

3-Benzylhexahydropyrrolo[1,2-a]pyrazine-1,4-dione [cyclo(Pro-Phe)] was synthesized by cyclization of prolylphenylalanine and phenylalanylproline methyl esters which were prepared from the corresponding Boc-protected amino acids.

AGRICULTURAL CHEMICAL CONTAINING 2,5-DIKETOPIPERAZINE DERIVATIVE AS ACTIVE INGREDIENT

Disclosed herein is an agricultural agent containing a 2,5-diketopiperazine derivative capable of controlling plant diseases and promoting plant growth or an agriculturally acceptable salt thereof as an active ingredient.

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.

Solid-phase synthesis of phenylalanine containing peptides using a traceless triazene linker

The use of a triazene function to anchor phenylalanine to a polymeric support through its side chain is reported. To prove the usefulness of this strategy in solid-phase peptide synthesis, several bioactive peptides have been prepared including cyclic, C-modified, and protected peptides. The triazene linkage is formed by coupling the diazonium salt of Fmoc-Phe(pNH 2)-OAllyl to a MBHA-polystyrene resin previously functionalized with isonipecotic acid (90%). Further assembly of the peptide chain, cleavage from the resin using 2-5% TFA in DCM, and reduction of the resulting diazonium salt of the peptide with FeSO4-7H2O in DMF afforded the desired products in high purities (73-94%).

An efficient green synthesis of proline-based cyclic dipeptides under water-mediated catalyst-free conditions

l-Proline-based cyclic dipeptides were synthesized from N-Boc-protected dipeptide methyl esters under catalyst-free condition using water as a solvent. One-pot deprotection and cyclization have been used as the key steps, providing an efficient and environmentally friendly approach. Clean reaction conditions, easy isolation, and good yields of cyclic dipeptides are the salient features of the proposed methodology.

Enantioselective Henry reaction catalyzed by C2-symmetric chiral diamine-copper(II) complex

A copper(II) complex of C2-symmetric diamine has been proved to be an efficient catalyst for the enantioselective Henry reaction between nitroalkanes and various aldehydes to provide β-hydroxy nitroalkanes in high yields (up to 97%), moderate diastereoselectivities (up to 71:29) and excellent enantiomeric excesses (up to 96%). The chiral nitroaldol adduct obtained has been further converted into chiral aziridine in few steps.

REAGENT FOR ORGANIC SYNTHESIS AND METHOD OF ORGANIC SYNTHESIS REACTION WITH THE REAGENT

A reagent for organic synthesis with which a chemical reaction can be conducted in a liquid phase and unnecessary compound(s) can be easily separated at low cost from the liquid phase after completion of the reaction. The reagent for organic synthesis reversibly changes from a liquid-phase state to a solid-phase state with changes in solution composition and/or solution temperature, and is for use in organic synthesis reactions. This reagent for organic syntheses facilitates process development. With the reagent, research on and development of, e.g., medicines through, e.g., compound library synthesis, etc. can be accelerated. It can hence contribute to technical innovations in the biochemical industry and chemical industry.