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PubMed · 9680064

Cryochemistry: freezing effect on peptide coupling in different organic solutions.

T Vajda·G Szókán·M Hollósi
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Abstract

The freezing effect on peptide coupling in organic solutions of different polarity has been investigated and compared with the results obtained in liquid phase. The model reaction of DCC-activated coupling of Boc-Ala-Phe-OH with H-Ala-OBu(t) has been carried out in dioxane, dimethylsulfoxide and formamide, as well as in mixtures (90%/10%, v/v) of dioxane with acetonitrile, dimethylformamide, dimethylsulfoxide and formamide. The reactions have been traced and evaluated by RP-HPLC analysis. Freezing the reaction mixture resulted in all cases in a significant suppression of the N-dipeptidylurea side-product formation together with a slight decrease of tripeptide epimerization. The coupling yields and the side effects depended on the solvent, with the dioxane and dioxane/acetonitrile mixture produced the best results. The role of freezing and solvent in the improved results is discussed.

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Chromatography, High Pressure LiquidFreezingOrganic ChemicalsPeptidesSolventsComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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T Vajda, G Szókán, M Hollósi. 1998. Cryochemistry: freezing effect on peptide coupling in different organic solutions.. https://doi.org/10.1002/(sici)1099-1387(199806)4%3A4%253c300%3A%3Aaid-psc148%253e3.0.co%3B2-i

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