164861-48-7

Upstream product

• 13123-00-7 (2S)-2-[((2S)-2-{[(benzyloxy)carbonyl]amino}-3-phenylpropanoyl)amino]-3-methylbutanoic acid 
• 7531-52-4 L-prolinamide 
• 1161-13-3 N-Cbz-L-Phe 
• 71989-31-6 Fmoc-Pro-OH 
• 654676-72-9 4-nitro-benzenesulfonic acid [1,2,3]triazolo[4,5-b]pyridin-3-yl ester 
• 654676-67-2 2-nitro-benzenesulfonic acid [1,2,3]triazolo[4,5-b]pyridin-3-yl ester 
• 54769-58-3 1H-benzo[d][1,2,3]triazol-1-yl 4-nitrobenzenesulfonate 
• 69193-11-9 Z-L-Phe-L-Val-NH₂ 
• 68858-20-8 Fmoc-Val-OH 

Relevant academic research and scientific papers

Peptide synthesis beyond DMF: THF and ACN as excellent and friendlier alternatives

To date, DMF has been considered as the only solvent suitable for peptide synthesis. Here we demonstrate the capacity of THF and ACN, which are friendlier solvents than DMF, to yield the product in higher purity than DMF. Using various peptide models, both THF and ACN reduced racemization in solution-phase and solid-phase synthesis when compared with DMF. Moreover, the use of ACN and THF in the solid-phase peptide synthesis of hindered peptides, such as Aib-enkephalin pentapeptide and Aib-ACP decapeptide, in combination with a complete polyethylene glycol resin (ChemMatrix), gave a better coupling efficiency than DMF. This journal is

Oxyma-T, expanding the arsenal of coupling reagents

Herein, we report a new oxime-based additive (Oxyma-T) with a similar structure to HONM and Oxyma-B for use in peptide synthesis. Oxyma-T produces less racemization than HOBt, HOAt, OxymaPure, and Oxyma-B during the stepwise solution-phase synthesis of Z-Phg-Pro-NH2. Moreover, it exhibits superior coupling efficiency in comparison to HOBt during the SPPS of an Aib-enkephalin pentapeptide. Racemization during segment coupling follows the order: HOBt?>?Oxyma-T?>?OxymaPure?>?HOAt?>?Oxyma-B.

TOMBU and COMBU as novel uronium-type peptide coupling reagents derived from oxyma-b

Here we describe two novel uronium salts, TOMBU and COMBU, derived from the recently described Oxyma-B for use in peptide bond synthesis. These coupling reagents are more stable than COMU in DMF. Furthermore, using various peptide synthetic models in solu

BOP-OXy, BOP-OBt, and BOP-OAt: Novel organophosphinic coupling reagents useful for solution and solid-phase peptide synthesis

Stand-alone coupling reagents derived from bis(2-oxo-3-oxazolidinyl) phosphorodiamidic chloride show efficient performance in solution and SPPS. In particular, the Oxyma Pure (Luxembourg Biotech., Tel Aviv, Israel) derivative shows the additional advantag

Addition of HOAt dramatically improves the effectiveness of pentafluorophenyl-based coupling reagents

In the course of comparing the effectiveness of several HOAt- and HOPfp- derived coupling reagents by cyclization and segment condensation of model sequences, using HPLC to follow the time course and to determine the outcome in terms of oligomerization an

EDC·HCl and potassium salts of oxyma and oxyma-b as superior coupling cocktails for peptide synthesis

Nowadays, DIC is the most widely used carbodiimide for solid-phase peptide synthesis, while EDC·HCl is mostly used only for solution-phase synthesis. In this paper, we report new coupling cocktails containing EDC·HCl in combination with potassium salts of OxymaPure and Oxyma-B (i.e., K-Oxyma and K-Oxyma-B, respectively). These reagent cocktails gave spectacular purity compared to DIC/classical N-hydroxylamine derivatives in the solid-phase peptide synthesis of the Aib-enkephaline (Aib = 2-aminoisobutyric acid) pentapeptide (H-Tyr-Aib-Aib-Phe-Leu-NH2), a hindered peptide. Furthermore, we found that the EDC·HCl/K-Oxyma combination can be used with DMF, THF, or MeCN as the solvent. The optimized cocktail gave less racemization than benzotriazole derivatives, but slightly more than OxymaPure and Oxyma-B during stepwise solution-phase peptide synthesis. We have shown that combinations of rather simple and green reagents, such as EDC·HCl and the potassium salt of OxymaPure or Oxyma-B, give unique results in terms of yield and low levels of racemization. We envisage a broad application of these reagents in solid-phase and solution synthesis, and especially in the preparation of peptide-based nanomaterials.

A novel family of onium salts based upon isonitroso meldrum's acid proves useful as peptide coupling reagents

A new family of uronium salts (HTMU, HMMU, and HDmPyMU) based on isonitroso Meldrum's acid (HONM) are reported as stand-alone coupling reagents. Amide bond formation with the use of these reagents occurred more quickly than that with other uronium salts as a result of the presence of a neighboring group effect with a cyclic structure. Thus, these novel onium salts were often more effective in the acylation of poor nucleophiles and in the control of optical purity than related Oxyma- and benzotriazole-based reagents. Among the HONM derivatives, HMMU showed the best performance in reducing racemization and assembling demanding sequences such as the Aib-ACP decapeptide or analogues of Leu-enkephalin pentapeptide, Furthermore, the scope and limitations of the use of HONM as an additive in combination with carbodiimides is discussed.

Ethyl 2-Cyano-2-(hydroxyimino)acetate (Oxyma): An efficient and convenient additive used with tetramethylfluoroformamidinium hexafluorophosphate (TFFH) to replace 1-hydroxybenzotriazole (HOBt) and 1-hydroxy-7-azabenzotriazole (HOAt) during peptide synthesis

The appropriateness of ethyl 2-cyano-2-(hydroxyimino)acetate (Oxyma) as a substitute for benzotriazole-based additives, for use in the TFFH approach for peptide synthesis, is discussed in terms of its capacity to control racemization, its coupling efficiency in difficult couplings either for stepwise or segment coupling in solution- and solid-phase coupling. In addition, Boc-based solution-phase peptide synthesis and its stability in the presence of growing peptide chains were studied. Oxyma displayed remarkable results in terms of racemization depression together with impressive coupling efficiency in both solution- and solid-phase synthesis. Furthermore, Oxyma suggests a lower risk of explosion than HOBt and HOAt.

PyOxP and PyOxB: The Oxyma-based novel family of phosphonium salts

Recent studies described the great impact of a non-benzotriazolic family of coupling reagents based on ethyl 2-cyano-2-(hydroxyimino)acetate, Oxyma, as a powerful coupling methodology for peptide synthesis. Here we present the synthesis and evaluation of the derived phosphonium salts O-[(1-cyano-2-ethoxy- 2-oxoethylidene)amino]-oxytri(pyrrolidin-1-yl) phosphonium hexafluorophosphate (PyOxP) and tetrafluoroborate (PyOxB). Both coupling reagents exhibited higher capacity to suppress racemization in various peptide models and enhanced solubility in DMF and DCM than benzotriazole-based reagents. In addition, the hexafluorophosphate analog PyOxP, combined excellent stability with outstanding efficiency in the assembly of demanding penta and decapeptides that include consecutive Aib residues. Cyclization models revealed the advantages of PyOxP, which rendered a higher percentage of cyclic material than other known potent phosphonium salts.

Oxyma: An efficient additive for peptide synthesis to replace the benzotriazole-based HOBt and HOAt with a lower risk of explosion

Oxyma [ethyl 2-cyano-2-(hydroxyimino)acetate] has been tested as an additive for use in the carbodiimide approach for formation of peptide bonds. Its performance in relation to those of HOBt and HOAt, which have recently been reported to exhibit explosive properties, is reported. Oxyma displayed a remarkable capacity to inhibit racemization, together with im-pressive coupling efficiency in both automated and manual synthesis, superior to those of HOBt and at least comparable to those of HOAt, and surpassing the latter coupling agent in the more demanding peptide models. Stability assays showed that there was no risk of capping the resin under standard coupling conditions. Finally, calorimetry assays (DSC and ARC) showed decomposition profiles for benzotriazolebased additives that were consistent with their reported explosivities and suggested a lower risk of explosion in the case of Oxyma.