摘要:

AbstractA simple method is described for the preparation of [3H]bilirubin IX‐α by the reduction of biliverdin IX‐α using sodium boro[3H]hydride. The [3H]bilirubin is obtained with a high specific radioactivity and the tritium is located at the methylene bridge (C‐10). Oxidation of the [3H]bilirubin with chloranil results in some loss of tritium from C‐10 and [3H]biliverdin is

ISSN:0362-4803    

DOI:10.1002/jlcr.2580181002

出版商:John Wiley&Sons, Ltd.    

年代:1981

数据来源: WILEY

摘要:

AbstractA general procedure for the synthesis of labelled hydrocarbons by catalytic isomerization in a microreactor is described.At four studied reactions (synthesis of isohexanes, methylcyclopentane, methylcyclopentenes and xylenes) the thermodynamically expected equilibrium concentrations could be approached. For product separation a direct coupling of the microreactor with a prep‐scale gaschromatographic unit is favorabl

ISSN:0362-4803    

DOI:10.1002/jlcr.2580181003

出版商:John Wiley&Sons, Ltd.    

年代:1981

数据来源: WILEY

摘要:

AbstractSodium 6‐[ (R)‐2‐(4‐hydroxy‐1,5‐naphthyridine‐4‐14C‐3‐carboxy‐14C‐amido)‐2‐phenylacetamido]penicillanate (apalcillin‐14C sodium) (1) was synthesized for use in metabolic studies. Reaction of ethyl malonate‐1‐14C (2) with ethyl orthoformate in the presence of zinc chloride gave ethyl ethoxymethylenemalonatel‐14C (3), which was condensed with 3‐aminopyridine to give the aminopyridylacrylate‐14C (4). Cyclization of4in boiling. Dowtherm A followed by hydrolysis of the resulting ester gave 4‐hydroxy‐1, 5‐naphthyridine‐4‐14C‐3‐carboxylic‐14C acid (5). Condensation of5with 6‐[ (R)‐2‐amino‐2‐phenylacetamido]penicillanic acid by the activated ester method yielded apalcillin‐14C triethylamonium (7), which in turn was treated with sodium 2‐ethylhexanoate, g

ISSN:0362-4803    

DOI:10.1002/jlcr.2580181004

出版商:John Wiley&Sons, Ltd.    

年代:1981

数据来源: WILEY

摘要:

AbstractThe preparation of pure octahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine (HMX) labelled with nitrogen‐15 and deuterium was accomplished by sequential nitrolysis of appropriately labelled octahydro‐1,5‐diacetyl‐3,7‐endomethylene‐1,3,5,7‐tetrazocine. The latter compounds were obtained from the reaction of acetic anhydride with hexamethylenetetramine that was specifically labelled by the reaction of the appropriate for

ISSN:0362-4803    

DOI:10.1002/jlcr.2580181005

出版商:John Wiley&Sons, Ltd.    

年代:1981

数据来源: WILEY

摘要:

AbstractOxidation of 5α‐cholest‐8(14)‐ene‐3β,7α,15α‐triol with silver carbonate‐celite gave 5α‐cholest‐8(14)‐ene‐7α,15α‐diol‐3‐one in 88% yield. Treatment of the latter compound with tritiated water under basic conditions gave a labeled product which was reduced with lithium tri‐tert‐butoxyaluminum hydride in tetrahydrofuran to give [2,4–H]5α‐cholest‐8(14)‐ene‐3β,7α,15α‐triol which was obtained in high purity after medium pressure liquid chromatography in the form of its triacetate derivative. Treatment of the labeled triol with concentrated hydrochloric acid in 95% ethanol gave

ISSN:0362-4803    

DOI:10.1002/jlcr.2580181006

出版商:John Wiley&Sons, Ltd.    

年代:1981

数据来源: WILEY

摘要:

AbstractCrystalline [11β‐3H]prostacyclin (PGI2) sodium salt (5) was prepared from prostaglandin D2(PGD2) methyl ester (1). Reduction of PGD2methyl ester with sodium borotritide afforded [11β‐3H]prostaglandin F2α (PGF2α) methyl ester (2a) in 57% radiochemical yield. [11β‐3H]PGF2α methyl ester was convertedvia(5R, 6R)‐ and (5S, 6S)‐5‐iodo‐[11β‐3H]prostaglandin I1methyl ester (3) to [11β‐3H]‐prostacyclin methyl ester (4). Carefully controlled hydrolysis of4produced crystalline [11β‐3H]PGI2sodium salt which was shown to be>95% pure by means of high performance liquid chromatographic (HPLC) analysis. The overall yield from [11β‐3H]PGF2α methyl ester to [11β‐3H]PGI2sodium salt was 53%. [11β‐3H]PGI2sodium salt with a specific activity of 502 μCi/mg has only limited radiochemical stability. Its radiochemical purity declined 15% after three weeks of

ISSN:0362-4803    

DOI:10.1002/jlcr.2580181007

出版商:John Wiley&Sons, Ltd.    

年代:1981

数据来源: WILEY

摘要:

AbstractThe studies on the stability, analysis and purification of several14C‐ and3H‐labeled polycyclic aromatic hydrocarbons such as benzo[a]‐pyrene, benzo[e]pyrene, and dibenz[a,c]anthracene and their metabolites such as dihydrodiols, phenols, and tetrahydrodiol epoxides are rep

ISSN:0362-4803    

DOI:10.1002/jlcr.2580181008

出版商:John Wiley&Sons, Ltd.    

年代:1981

数据来源: WILEY

摘要:

Abstract6‐Lithiobenzo[a]pyrene was carbonated to produce benzo[a]pyrene‐6‐carboxylic‐14C acid, which was in turn used in the preparation of several derivatives. Methylation to the ester was followed by LiAlH4reduction to 6‐hydroxymethyl‐14C‐benzo[a]pyrene. An efficient oxidation using DDQ produced the corresponding aldehyde. Direct reduction of the ester using LiAlH4and AlCl3produced 6‐methyl‐14

ISSN:0362-4803    

DOI:10.1002/jlcr.2580181009

出版商:John Wiley&Sons, Ltd.    

年代:1981

数据来源: WILEY

摘要:

AbstractThe syntheses of 1‐pyrenyloxirane‐3,6,8‐3H1,7, and its precursor, pyrene‐1,3,6,8‐3H1,4, are described. The synthesis pathway includes a novel preparation of4from 1‐pyrenyllithium and tritiated water in theore

ISSN:0362-4803    

DOI:10.1002/jlcr.2580181010

出版商:John Wiley&Sons, Ltd.    

年代:1981

数据来源: WILEY

摘要:

AbstractA paper chromatography technique using 33% w/v aqueous solution of ammonium sulphate as a solvent has been applied for fast separation of inorganic radioactive iodide from labelled organic compound in the analysis of some iodoorganic radiopharmaceuticals of common use.L‐triiodothyronine, L‐thyroxine, Rose Bengal and bromosulphthalein are retained at the starting spot while iodide migrates at Rf0.5. The separation is obtained at a development path of 5cm in about 10min.Sodium o‐iodohippurate, however, migrated at Rf0.4 and its separation from inorganic iodide was not achieved under the conditions emp

ISSN:0362-4803    

DOI:10.1002/jlcr.2580181011

出版商:John Wiley&Sons, Ltd.    

年代:1981

数据来源: WILEY