Méthode de marquage de groupes carboxyliques dans les peptides. Propriétés chromatographiques et autres,de peptide-p,p′-dimapa-anilides

Résumé Les auteurs décrivent une méthode efficate et les conditions (faibles valeurs de pH, milieu dioxane/eau (1∶2), carbodiimide hydrosoluble) de formation de peptides colorés par réaction de leur groupe carboxylique avec un colorant aminé (par exemple: 1(4-diméthylamino-1 phénylazo)-4-aminobenzène=p,p′-dimapa-aniline), sans polymérisation du peptide non-protégé. Quelques méthodes chromatographiques, faciles à mettre en oeuvre, pour l'isolement de peptide-p,p′-dimapa-anilides et quelques propriétés de ces nouveaux composés (peptides-C-colorés) sont présentées.

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Method for labelling carboxylic groups in peptides. Chromatographic and other properties of peptide-p,p′-dimapa-anilides

Summary The authors describe an effective method and the conditions (low pH values, dioxane/water (1∶2) media, watersoluble carbodiimide) for making coloured carboxylic peptides from amino-dye (i.e.: 1(4-dimethylamino-1 phenylazo)-4-aminobenzene=p,p′-dimapa-aniline), without polymerisation of unprotected peptide. Some easy chromatographic methods for isolation of peptide-p,p′-dimapa-anilides and some properties of these new compounds (C-dyed-peptides) are given.

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Caesium as counter-ion in the anionic polymerization of ethylene oxide—II: Kinetics in hmpt

Results are reported for the kinetics of the anionic polymerization of ethylene oxide in hexamethylphosphoramide using the caesium alkoxide of the monoethylether of diethylene glycol as initiator at 40·0°.The reactions were found to be first order in monomer and 0·5 in initiator; rates are depressed by adding caesium tetraphenyl boride. These results indicate that propagation takes place by free ions and ion pairs; the respective propagation rate constants are k_(?) = 22 and k_(±) = 0·2 M 'sec.     

Gas chromatographic determination of estrone,estradiol and estriol in non-pregnancy plasma

Summary A gas Chromatographic method for the determination of estrone, estradiol and estriol in plasma of normal females is described. Purification is done by means of TLC of the free compounds and the acetates and quantitation is achieved by electron capture-gas chromatography of the estrogen heptafluorobutyrates. Experiments on the validation of the method are described along with some examples of its application.

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Zusammenfassung Eine gaschromatographische Methode zur Bestimmung von Östron, Östradiol und Östriol im normalen weiblichen Plasma wurde beschrieben. Die Reinigung erfolgte durch Dünnschichtchromatographie der freien Verbindungen und ihrer Acetate. Die quantitative Bestimmung wurde gaschromatographisch mit Hilfe eines Elektroneneinfangdetektors an Hand der Östrogenheptafluorobutyrate bewerkstelligt. Versuche zur Bewertung dieser Methode sowie Beispiele für ihre Anwendung wurden beschrieben.

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Supported by USPHS Grants AM 09908 and RCDA 5 K 3-AM-31, 321 (S. K.) and a grant from the Ford Foundation.     

Reactions of SH-Substituted Purine Bases with Glycidol

The regioselectivity of S-alkylation of SH-substituted purine bases with glycidol tends to grow with decreasing temperature. A procedure was developed for epoxidation of these compounds in wet liquid ammonia. The products were tested for immunostimulating activity.