Description

• General description: Oxyma Pure (Ethyl cyano(hydroxyimino)acetate) is a non-explosive alternative to the canonical peptide coupling additive N-hydroxybenzotriazole (HOBt).[1] When used in place of HOBt in carbodiimide-mediated peptide bond formation, it provides products in higher yields with less racemization. The combination of Oxyma Pure/diisopropylcarbodiimide (DIC) has proven to be particularly effective in microwave-assisted peptide synthesis.[2]The generation of toxic hydrogen cyanide (HCN) from the reaction between Oxyma Pure and DIC has been observed.[3] Fortunately, this side reaction can be eliminated by substituting DIC for the more hindered t-butylethylcarbodiimide.[4]Associated Protocols and Technical ArticlesGuide to Selection of Coupling ReagentsLiterature references:[1] R. Subirós-Funosas, et al. (2009) Chem. Eur. J., 15, 9394[2] J. Collins , et al. (2014) Org . Lett ., 16, 940.[3] A. D. McFarland (2019) Org. Process Res. Dev., 23, 2099.[4] S. R. Manne, et al (2022) Org. Process Res. Dev., 26, 2894.
• Application: Further applications of Oxyma Pure: Use in the synthesis of difficult peptides.[5] As an acidic modifier to prevent aspartimide formation.[6]
• Features and Benefits: Can be used in place of HOBt in carbodiimide-mediated coupling reactions without change of protocolIt gives results comparable to HOAt in step-wise solid-phase synthesisLess epimerization than HOBt in fragment condensation reactions
• Analysis Note: Color (visual): white to slight yellow to beigeAppearance of substance (visual): crystalline powderAssay (HPLC, area%): ≥ 99.0 % (a/a)Identity (IR): passes testSolubility (12,5 mmol in 25 ml DMF): clearly soluble
• Legal Information: Novabiochem is a registered trademark of Merck KGaA, Darmstadt, Germany