摘要:

AbstractIodinated peptides or proteins (125I,131I) are used as tracers for radioimmono assays and for detection in biological systems. The labelling takes place on the aromatic side chains.However, when disulfide bridges are present, iodination must be carried out under conditions preventing their degradation. The rate of iodination of L‐tyrosine, L‐histidine and L‐histidine containing peptides by iodine monochloride (ICI) are studied by spectroscopy. Free hitidine increases the hydrolysis rate of aqueous solution of ICI. The interactions between ICI and some simple disulfide are investigated by circular dichroism measurements. These reactions are presented as models for degradation of disulfide bridges in peptide or protein during the iodination pr

ISSN:0022-2135    

DOI:10.1002/jlcr.2590100102

出版商:John Wiley&Sons, Ltd.    

年代:1974

数据来源: WILEY

摘要:

AbstractThe synthesis and purification of α‐melanotropin labelled with tritium on the tyrosine residue is described. The hormone possesses a specific radioactivity of 2.8 Ci/mmole, which enables its application in studying transport processes, metabolism and mechanism of hormone acti

ISSN:0022-2135    

DOI:10.1002/jlcr.2590100103

出版商:John Wiley&Sons, Ltd.    

年代:1974

数据来源: WILEY

摘要:

Abstract3H‐ and14C‐Labelled doisynolic acid was prepared from 6,7‐3H‐, 2,4,6,7‐3H‐ and 4‐14C‐labelled oestradiol and oestrone by a regulated alkali fusion. Labelled marrianolic acid was similarly prepared from labelled oestriol. Unstability of regiospecific tritium labels in alkali was observed by use of double lab

ISSN:0022-2135    

DOI:10.1002/jlcr.2590100104

出版商:John Wiley&Sons, Ltd.    

年代:1974

数据来源: WILEY

摘要:

AbstractEthyl esters of 2‐cyanoacetic, 3‐cyanopropionic and 4‐cyanobutyric acids ‐14CN were prepared by reaction of the appropriate halogenated esters with potassium cyanide‐14C. Conversion of these cyanoesters into iminoether hydrochlorides and subsequent thermal decomposition gave ethyl esters of malonamic, succinamic and glutaramic acids

ISSN:0022-2135    

DOI:10.1002/jlcr.2590100105

出版商:John Wiley&Sons, Ltd.    

年代:1974

数据来源: WILEY

摘要:

AbstractMethyl sterculate, a cyclopropenoid fatty acid, has been synthesized with carbon‐14 as the methylene carbon in the cyclopropene rin

ISSN:0022-2135    

DOI:10.1002/jlcr.2590100106

出版商:John Wiley&Sons, Ltd.    

年代:1974

数据来源: WILEY

摘要:

AbstractLa synthèse de la dl‐noréphédrine (méthyle14C) en deux stades, à partir de l'α‐N, N‐dibenzylaminoacétophénone et de I14CH3est décrite. Après purification par chromatographie sur résine échangeuse d'ions AG 50 W‐X2 on obtient la dl‐noréphédrine (méthyle14C) HCl avec un rendement radiochimique de 31% par rapport à14CO3Ba, activité spécifique: 55 mCi/mM. L'analyse par électrophorèse sur papier associée à la chromatographie sur papier et en couche mince permet de contrǒler la pureté radio

ISSN:0022-2135    

DOI:10.1002/jlcr.2590100107

出版商:John Wiley&Sons, Ltd.    

年代:1974

数据来源: WILEY

摘要:

AbstractCatalytic reductive dehalogenation of 5‐bromo‐6‐azauracil with carrier‐free tritium led to 6‐azauracil‐5‐3H of a molar activity of 19.0 Ci/mmole. The reaction conditions for the catalytic reductive dehalogenation were examined in tracer experiments. Microbial transformation was used for the preparation of 6‐azauridine‐5‐3H from 6‐azauracil‐5‐3H. 6‐Azauridine‐5‐3‐ H was prepared at a molar activity of 18.8 Ci/mmole. In both compounds the stability of tritium was investiga

ISSN:0022-2135    

DOI:10.1002/jlcr.2590100108

出版商:John Wiley&Sons, Ltd.    

年代:1974

数据来源: WILEY

摘要:

Abstract8‐Chloro‐6‐phenyl‐4H‐s‐triazolo [4,3‐a] [1,4]benzodiazepine (D‐40TA)‐1‐14C (V‐14C) was synthesized by the reaction of formic acid‐14C with 7‐chloro‐2‐hydrazino‐5‐phenyl‐3H‐1, 4‐benzodiazepine in the presence of N,N′‐carbonylbis (2‐methylimidazole). The overall radio

ISSN:0022-2135    

DOI:10.1002/jlcr.2590100109

出版商:John Wiley&Sons, Ltd.    

年代:1974

数据来源: WILEY

摘要:

Abstractdl‐Nornicotine‐2′‐14C was synthesized in four steps. Nicotinic acid (carboxyl‐14C) was first esterified with diazomethane to yield methyl nicotinate (carboxyl‐14C). The ester was condensed with 3‐lithio‐N‐trimethylsilyl‐2‐pyrrolidone to give 3‐nicotinoyl‐N‐trimethyslsilyl‐2‐pyrrolidone (ketone carbonyl‐14C), which was hydrolyzed and decarboxylated in concentrated hydrochloric acid to give myosmine‐2′‐14C.Reduction of myosmine‐2′14C gave nornicotine‐2′‐14C. Reaction of nornicotine‐2′‐14C in hydrochloric acid with sodium nitrite gaveN′‐nitrosonornicotine‐2′‐14C. Purification of labelled myosmine, nornicotine, andN′‐nitroso

ISSN:0022-2135    

DOI:10.1002/jlcr.2590100110

出版商:John Wiley&Sons, Ltd.    

年代:1974

数据来源: WILEY

摘要:

AbstractMethyl iodide14C is reacted with lithium p‐methoxy phenylacetylenide to give with a 85% yield 1‐p‐methoxy‐phenyl‐1‐propyne‐3‐14C.Reduction of the latter with LiAlH4leads to a mixture of trans anethole‐3‐14C (85%) and cis anethole (15%) with a 55% yield. After preparative gas chromatography pure trans anethole‐3‐14C is isolated with an overall yield of 20% based on methyl iodide14C.Benzene14C (U) is brominated into bromobenzene14C (U) which by copper catalysed alcaline hydrolysis gives phenol14C (U). Methylation of the latter leads to anisole14C (U).Gattermann reaction with the latter gives a mixture of o‐and p‐méthoxy‐benzaldehyde14C (U) in a 80% yield from which pure para isomere is isolated by colwmn chromatography with a 42% yield based on anisole14C (U). Treated with ethyl magensium iodide p‐methoxybenzaldehyde leads to 1‐p‐methoxy‐phenyl‐1‐propanol (ring14C‐U) the dehydration of which by heating with Al2O3gives a mixture of trans anethole (ring14C‐U) (80%) and cis anethole (ring14C‐U) (20%). After preparative gas chromatography pure trans anethole (ring14C‐U) is isolated with a

ISSN:0022-2135    

DOI:10.1002/jlcr.2590100111

出版商:John Wiley&Sons, Ltd.    

年代:1974

数据来源: WILEY