摘要:

AbstractThe introduction of bulky residue (s) in linear enkephalin‐related hexapeptides represents a new approach in the design of selective probes for δ‐opioid receptors, displaying the appropriate criteria to investigate biological and pharmacological properties of the assumed binding site (δ) of endogenous enkephalins. The selectivities and high affinities of Tyr‐D‐Ser(O‐t‐Bu)‐Gly‐Phe‐Leu‐Thr(DSTBULET) and especially Tyr‐D‐Ser(O‐T‐Bu)‐Gly‐Phe‐Leu‐Thr(O‐t‐Bu) (BUBU) associated with a satisfactory resistance to peptidases, make them the most suitable δ–probes reported to date. In the present paper, we report the synthesis of DSTBULET and BUBU under tritiated forms with high specific radioactivities. These radio‐labelled probes will enable extensive in vitro and in vivo investigations of

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280802

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractA series of p‐carboxyalkylphenylglyoxal and p‐carboxyalkyl‐1,2‐diketo‐bis‐(N4‐methylthiosemicarbazone) bifunctional ligands (TSC) have been prepared and evaluated for use in binding radioisotopes of copper to antibodies. We have developed an improved synthesis of the requisite α‐ketoaldehyde and 1,2‐diketone substrates used for derivatization to the bis‐TSC bifunctional chelates. This approach utilizes a modified Kornblum method and provides a simple alternative to the usual method for fabrication of the 1,2‐bis‐TSC ligands, which avoids the use of highly toxic selenium dioxide for oxidation of substituted acetophenones to 1,2 dicarbonyl compounds. The overall yields of the bis‐TSC chelates using this procedure were 8‐60%. The effects of the alkyl chain length and substitution on the C‐2 position on p‐carboxyalkylphenyl‐1,2‐diketo bis‐TSC bifunctional chelate for attaching radioisotopes of copper to proteins were studied. Following complexing copper‐64 or copper‐67 to the bis‐TSC chelate, the acid moiety of the TSC chelate was activated as the tetrafluorophenyl ester. The copper‐labeled activated TSC chelate was attached to bovine serum albumin under mild conditions in 3% to 40% yield. These studies have demonstrated that the shorter chain analogues of the TSC chelates from the 1,2

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280803

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractSodium 3‐ethyl‐7‐isopropylazulene‐1‐sulfonate1, which has been found to be a potent and chemically stable agent having anti‐inflammatory and anti‐ulcerous activity, was synthesized in14C‐labelled form by using potassium [14C]‐cyanide.14C‐Labelled1with a specific activity of 9.02 mCi/mmol was prepared in eight steps in 21.9% overall chemical yield from 3‐(t‐butyldiphenylsil

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280804

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractA synthetic procedure for producing (±)‐5‐[4‐(6‐hydroxy‐2, 5, 7, 8‐tetramethylchroman‐2‐ylmethoxy) benzyl]‐5‐14C‐thiazolidine‐2, 4‐dione (14C‐labelled CS‐045) is described. The radiolabel is introduced using [5‐14C] thiazolidine‐

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280805

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractSyntheses of [phenyl‐14C]4′‐[[1‐[2‐(6‐Methyl‐2‐pyridyl)ethyl]‐4‐piperidyl]carbonyl]methanesulfon‐anilide dihydrochloride dihydrate (1) (14C‐E‐4031) and its pyridylpropyl analogue (2), that are selective class III antiarrhythmic agents, are described. A modified Michael reaction of (6), a key intermediate amine prepared from [U14C]aniline hydrochloride, with 6‐methyl‐2‐vinylpyridine (7) and alkylation of (6) with 4‐(3‐chloropropyl) pyridine (8) respectively produced compounds,

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280806

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe syntheses of [13C]‐ and [14C]ellagic acid (EA) were accomplished by reacting [13C]‐ or [14C]CO2with metalated 3,4,5‐trimethoxybenzene to afford trimethylgallic acid which was O‐demethylated with hydroiodic acid. Oxidation of the resulting labeled gallic acid with potassium persulfate producedEA.The yields of trimethylgallic acid andEAbased on [14C]BaCO3are 48 and 1%, respectively. Final purification ofEAinvolved the use of preparative reversed‐phase HPLC and removal of the eluent buffer salts on a C18Sep‐Pak column. The isotopic purity of [13C]EAwas determined by13C NMR. The [14C]EAhad 99% radiochemical purity as determined by analytical HPLC and a specific activity of ca. 1

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280807

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractPreparation of the title compound, tracer substances required for the development of the fasciollide clorsulon, is described. The ring‐u‐14C variety was obtained in 42.2% yield overall from purchased [ring‐u‐14C]aceto

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280808

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractA method is described for the synthesis, purification and radiolabelling of 2‐{5‐(4‐iodophenyl)pentyl}oxirane‐2‐carboxylic acid (I‐POCA). This new compound was synthesized from 5‐phenyl‐pentylbromide (1), prepared via 5‐phenyl‐1‐pentanol and subsequently converted to diethyl 5‐phenylpentylmalonate (2). The latter on alkaline hydrolysis yielded ethyl 5‐phenyl‐pentylmalonate (3). Para‐substitution of iodine on the phenyl moiety of the monoester (3) was accomplished by reacting compound (3) with thallium trifluoroacetate (TTFA) and subsequently with KI. Oxidation of ethyl 7‐(4‐iodophenyl)‐2‐methyleneheptanoate (5), which was synthesized from the monoester, ethyl 5‐(4‐iodophenyl)pentylmalonate (4) yielded ethyl 2‐{5‐(4‐iodophenyl)pentyl}oxirane‐2‐carboxylate (6). The radiolabelling procedure was based on a Cu(I)Cl‐assisted, isotopic exchange reaction, which produced a no‐carrier‐added and regios

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280809

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe synthesis of 3,5‐bis (trideuteromethyl) pyrazole was achieved by reaction of perdeuterated acetylacetone with perdeuterated hydrazine hydrate. Some unsuccessful attempts using alternative routes are also describe

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280810

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe complex cis‐[Pt(NH3)282Br2] has been prepared as a possible model for cisplatin, cis‐[Pt(NH3)2Cl2]. The stability of cis‐[Pt(NH3)282Br2] was investigated in 0.9% saline solution and sterile water. In both cases the82Br label was rapidly displaced in the first hour (t1/2= 73 min and 96 min respectively). Thus, cis‐[Pt(NH3)282Br2]cannot be used for determining the fate of the labile ligands of ci

ISSN:0362-4803    

DOI:10.1002/jlcr.2580280811

出版商:John Wiley&Sons, Ltd.    

年代:1990

数据来源: WILEY