摘要:

AbstractAn efficient two‐step synthesis of the potential cholinergic neuronal mapping tracer [11C]methylaminobenzovesamicol (MABV) is described. Atert‐butoxycarbonyl protecting group was used to activate the aniline nitrogen of aminobenzovesamicol toward [11C]methyl iodide methylation under basic conditions. Following labeling, the protecting group was removed by brief acid treatment and the final product was purified by normal phase HPLC. The decay corrected yields of MABV are in the range of 30‐70 %, based on11CO2, with a specific activity of 0.5‐1.5 Ci/ μmol and synthesis time of less than 45 minutes. This new route makes clinical scale doses of this interesting compound available for human positron emission tomography

ISSN:0362-4803    

DOI:10.1002/jlcr.2580310402

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractA series of thirteen regiospecifically chlorine‐37 labeled polychlorodibenzo‐p‐dioxins were synthesized via the Sandmeyer reaction. Nitrochlorodibenzodioxins which were obtained by a base promoted condensation of catechols and dinitropolyhalobenzenes were reduced and converted to the diazonium salts. Chlorine‐37 was introduced using cuprous chloride‐37. The isotopic enrichment was in the ran

ISSN:0362-4803    

DOI:10.1002/jlcr.2580310403

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractA single step synthesis of the [14C‐ring]‐N‐tert‐butyl‐α‐phenylnitrone (1) starting from the [14C‐ring] benzaldehyde is described. The product is obtained in high yield (90%) with a good l

ISSN:0362-4803    

DOI:10.1002/jlcr.2580310404

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractEchinocandin B was catalytically reduced with hydrogen, deuterium, or tritium. HPLC analysis of the products showed that the labeled analogs exhibited a significant isotope effect relative to the unlabeled parent, with the elution order tritiated

ISSN:0362-4803    

DOI:10.1002/jlcr.2580310405

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractThe14C‐isotopomer of dapoxetine‐[14C] HCl (S(+)‐N,N‐dimethyl‐α‐[2‐(1‐naphthalenyloxy)ethyl‐2‐14C]benzenemethanamine hydrochloride,1a), a potent serotonin re‐uptake inhibitor has been prepared by a chiral synthesis, starting withtert.‐butyloxyphenylglycine (3). Borane reduction, followed by activation of the resulting alcohol4as its mesylate5b, provided the chiral starting material. The radiolabel was introduced by reaction of5bwith sodium cyanide‐[14C]. The desired product (1) was then elaborated from nitrile6a,bvia a five step synthesis in an overall

ISSN:0362-4803    

DOI:10.1002/jlcr.2580310406

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractDevelopment of an123I‐labeled glucose derivative that interacted with hexokinase was attempted. By introducing a benzene ring into the glucosamine molecule, we were able to secure a radioiodinated compound, N‐iodobenzoyl‐D‐glucosamine (BGA), with enhanced stability. As a result, a non‐competitive inhibitory agent on the hexokinase‐regulated phosphorylation reaction was achieved. The inhibitory action and lipophilic property of this novel compound were closely related to an amide bond in its structural configuration. Moreover, on investigating the biodistribution in mice, although this125I‐labeled compound did not display any uptake into the brain, it demonstrated rapid clearance from the blood with high systemic stability. From the above findings, it is highly possible to develop a clinically feasible123I‐labeled radioligand that can monitor the quantitative changes and biodistributio

ISSN:0362-4803    

DOI:10.1002/jlcr.2580310407

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractUniformly labeled (U)14C nicotinamide adenine dinucleotide phosphate (NADP+) was synthesized by phosphorylating [U‐14C]nicotinamide adenine dinucleotide (NAD+) in the presence of immobilized NAD+kinase. The 15 μCi (600 μL) synthesis consistently achieved yields between 80% and radiochemical purities greater than 95%. The [U‐14C]NADP+was purified by high performance anion‐exchange chromatography using a gradient elution of ammonium bicarbonate. This procedure may be applicable to the synthesis of other charged, UV‐absorbing products of enzyme‐catalyze

ISSN:0362-4803    

DOI:10.1002/jlcr.2580310408

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractHerbimycin A, an ansamycin antibiotic, is known to reverse the transformed phenotype of cells transfected with tyrosine kinase expressing oncogenes. The synthesis of [19‐3H] herbimycin A (1c), a potential tool for unraveling the mechanism of this reversal, is described. Reduction of 19‐bromoherbimycin A (4) employing zinc‐copper couple/tritiated water affords hydroquinone (5c) which, when treated with manganese dioxide, affo

ISSN:0362-4803    

DOI:10.1002/jlcr.2580310409

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

ISSN:0362-4803    

DOI:10.1002/jlcr.2580310401

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY