bluuebunny/crossref_metadata_2025_split huggingface dataset:
Can we predict reactivity for aromatic nucleophilic substitution with [18F]fluoride ion?
Authors: Rengan Ramesh , Chakraborty Pulak K. , Kilbourn Michael R. 
Published: October 2006

AbstractThe correlation between the 13C‐NMR chemical shift of the aromatic ring carbon bearing the leaving group and the yield of nucleophilic aromatic displacement with no‐carrier‐added [18F]fluoride ion was evaluated. In comparison of structurally analogous compounds (fluoro, nitro and trimethylammonium substituted benzaldehydes, benzophenones and benzonitriles), the 13C‐NMR chemical shift of the reactive aryl ring carbon correlated quite well with the [18F]fluorination yield (r2=0.87) for most but not all ring structures. Compounds with trimethylammonium leaving groups or methyl ring substituents were found to not fit the proposed correlation. Kinetic studies indicated clearly different rates of reaction for these compounds, with much higher than expected reactivity for the ccompounds with the cationic leaving group. Competition experiments suggest that low reactivity of methyl‐substituted rings may be due to conversion of [18F]fluoride to an unreactive form. Our results indicate that the correlation between [18F]fluorination yields for nucleophilic aromatic substitution reactions and the 13C NMR chemical shift of the aryl ring carbon bearing the leaving group is applicable to numerous structurally analogous compounds, but cannot be simply generalized to aromatic rings with different leaving groups or ring substituents.
A rapid synthesis of [fluoroacetyl‐18F]fluoromelatonin (Nω‐[18F]fluoroacetyl‐5‐methoxytryptamine), a potential diagnostic imaging agent
Authors: Tada Masao , Iwata Ren , Sugiyama Hiroshi , Sato Kazunori , Pascali Claudio , Fukuda Hiroshi , Kubota Kazuo , Kubota Roko , Takahashi Hiromu , Wakui Akira , Abe Yoshinao , Fujiwara Takehiko , Sato Tachio , Ido Tatsuo 
Published: October 2006

AbstractAn efficient synthesis of [fluoroacetyl‐18F]fluoromelatonin (Nω‐[18F]Fluoroacetyl‐5‐methoxytryptamine) starting from [18F]fluoride and ethyl p‐toluensulfonyloxyacetate is described. The total time required for its synthesis is ca. 90 min. The radiochemical yield, purity and specific activity (end of bombardment) of the desired compound are 14.2%,>98%, and 540 mCi/μmol, respectively.
Rapid, regiospecific syntheses of deuterium substituted 6‐[18F]fluorodopamine (α,α‐D2; β,β‐D2 and α,α,β,β‐D4) for mechanistic studies with positron emission tomography
Authors: Ding Yu‐Shin , Fowler Joanna S. , Wolf Alfred P. 
Published: October 2006

AbstractDoubly labeled (18F and deuterium) 6‐fluorodopamine (6‐FDA) isotopomers were prepared to probe the contribution of metabolism by monoamine oxidase (MAO) and dopamine β‐hydroxylase (DBH) on the kinetics of 6‐[18F]FDA in baboon heart. Specifically deuterated 6‐[18F]FDA‐α,α‐D2 and 6‐[18F]FDA‐β,β‐D2 were prepared by a six‐step synthesis starting from nucleophilic aromatic substitution with NCA [18F]fluoride on 6‐nitropiperonal or 6‐nitropiperonal‐D in a decay corrected radiochemical yield of 3‐10% (EOB). 6‐[18F]FDA‐α,α,β,β‐D4 was prepared in 4 steps in a radiochemical yield of 16‐20% (EOB) and specific activity 2‐5 Ci/μmol (EOB). The regiospecificity of deuterium substitution in the synthesis of 6‐[18F]FDA‐α,α,β,β‐D4 was verified using piperonal as a substrate.
The Synthesis of [methylenedioxy‐14C]paroxetine BRL 29060A
Authors: Lawrie K W M , Rustidge D C 
Published: October 2006

AbstractParoxetine (1), BRL 29060A, a potent antidepressant, has been prepared radiolabelled with carbon‐14 in the methylenedioxy group in 5 steps and 20.9% overall yield from [14C]dibromomethane. Two altenative preparations of 3,4‐[methylenedioxy‐14C]phenol (2) are also described.
Syntheses of 9‐(2′‐monoethylphosphonomethoxyethyl)‐8‐[14C]guanine ([14C]‐EPMG) and 9‐(2′‐phosphonomethoxyethyl)‐8‐[14C]guanine ([14C]‐PMEG)
Authors: Haynes U. J. , Swigor J. E. 
Published: October 2006

AbstractThe synthesis of the title compounds [14C]‐PMEG (5) and [14c]‐EPMG (6) are described. Treatment of [14C]guanine with acetic anhydride in 1‐methyl‐2‐pyrrolidinone gave [14C]N‐acetylguanine (2). Reaction with 2‐(diethylphosphonomethoxy) ethylmethanesulfonate in N,N‐dimethylformamide in the presence of potassium carbonate yielded 2‐N‐acetyl‐9(2′‐diethylphosphonomethoxyethyl)‐8‐[14C]‐guanine (3). Removal of the acetyl group with aqueous methylamine gave 9‐(2′‐ (diethylphosphonomethoxyethyl)‐8‐[14C]‐guanine (4). Treatment of the diethylphosphonate ester with sodium hydroxide and acidification with hydrochloric acid gave 9‐(2′‐(monoethylphosphonomethoxyethyl)‐ 8‐[14C]‐guanine (5). Silation of the diethylphosphonate ester with bromotrimethylsilane and treatment with water produced 9‐(2′‐phosphonomethyloxethyl)‐8‐[14C]guanine (6).
Radiolabelled amino acids: Synthesis of NG‐mesitylenesulfonyl‐N2‐[3H]methyl‐arginine
Authors: Landvatter Scott W. 
Published: October 2006

AbstractThe N2‐methyl amino acid NG‐mesitylenesulfonyl‐[3H]methylarginine has been prepared in high specific activity tritium labelled form by treating methyl N2‐2,4‐dimethoxybenzyl‐NG‐mesitylenesulfonyl‐arginate with [3H]methyl iodide and silver(I) oxide. Removal of the dimethoxybenzyl group by transfer hydrogenation (4.4% formic acid in methanol/Pd black) followed by saponification gave NG‐mesitylenesulfonyl‐[3H]methylarginine in 30‐38% overall from [3H]methyl iodide. This amino acid was ultimately used in the preparation of tritium labelled SK&F 107260 which is a cyclic peptide showing fibrinogen receptor antagonism.
Synthesis of D,L‐[2‐15N,5‐13C]glutamic acid
Authors: Laiuppa John C. , Lemaster David M. 
Published: October 2006

AbstractA one‐pot procedure is described for the synthesis of D,L‐[2‐15N,5‐13C]glutamic acid from 2‐bromo‐4–butyrolactone utilizing potassium 15N‐phthalimide and potassium 13C‐cyanide as label sources. Following a two column purification procedure, the final product is obtained in 38% yield based on the equimolar label sources.
Synthesis of α‐[14C]methyl and α‐[3H]methyl‐L‐tryptophan
Authors: Venkatachalam T. K. , Mzengeza S. , Diksic M. 
Published: October 2006

AbstractThe title compounds were synthesized starting from dimethyl (2S,3aR,8aS)‐(+)‐8‐(phenylsulfonyl)hexahydrophyrrolo[2,3‐b]indole‐1,2‐dicarboxylate. This compound on treatment with LDA followed by reaction with [14C]methyl iodide or [3H]methyl iodide gave the methyl substituted derivative which on treatment with trifloroacetic acid followed by hydrolysis with alkali gave the desired α‐[14C]methyl‐ or [3H]methy‐L‐tryptophan, respectively, in 50‐60% radiochemical yield.
Tc‐99m und deuterium markierte gehirn‐affine radiodiagnostika ‐ vergleich von HMPAO mit cytectren‐derivaten cyclischer amine
Authors: Wenzel M. , Klinge C. , Saidi M. 
Published: October 2006

AbstractHMPAO‐d2 and Deuterium labelled esters of Cytectrenecarbonic ester with alcohols of cyclic amines were synthesized and additional labelled with Tc‐99m. The organ distribution in rats showed a higher brain uptake of the cytectrene ester than HMPAO with a far higher Tc‐99m concentration ratio brain/blood.The deuterated compounds showed a lower Tc‐99m concentration in blood, but no higher uptake in brain.
Radiosynthesis of a photoaffinity probe for the cocaine receptor of the dopamine transporter: 3β‐(p‐chlorophenyl)tropan‐2β‐carboxylic acid m‐([125I]‐iodo)‐p‐azidophenethyl ester ([125I]‐RTI‐82)
Authors: Lever John R. , Carroll F. Ivy , Patel Amrat , Abraham Philip , Boja John , Lewin Anita , Lew Robert 
Published: October 2006

AbstractThe tropane alkaloid RTI‐82, an iodoarylazide, has been labeled with iodine‐125 for use as a photoaffinity probe for the cocaine binding site of the dopamine transporter. The one‐flask radiosynthesis involves nocarrier‐added electrophilic radioiodination of the corresponding aniline followed by diazotization and treatment with sodium azide. Isolation by reverse phase HPLC and solid phase extraction gives [125I]‐RTI‐82 in good yield (76 ± 7%, n=6), high radiochemical purity (>99.8%), and high specific radioactivity (1490 ‐ 1880 mCi/μmol).
Synthesis of [β,β,γ,γ,δ,δ,δ,–2H7]‐n‐butylbenzene
Authors: Kendall John T. , Spencer Thomas A. 
Published: October 2006

AbstractA convenient preparation of [β,β,γ,γ,δ,δ,δ–2H7]‐n‐butylbenzene has been achieved by base‐catalyzed isotopic exchange of 4‐phenyl‐2‐butanone followed by application of Vedejs' procedure for Clemmensen reduction in a deuteriated medium.
Synthesis of [14C]CI‐980, ethyl [5‐amino‐1,2‐dihydro‐2(S)‐methyl‐3‐[14C]phenylpyrido[3,4‐ 6]pyrazin‐7‐YL]carbamate isethionate salt, a tubulin‐binding, antimitotic, broad‐spectrum antitumor agent
Authors: Woo Peter W. K. , Lee Helen T. 
Published: October 2006

Abstract[14C]CI‐980 (14b) was synthesized in eight steps starting from [U‐14C]benzene (5), which was converted to bromo[14C]benzene (6) in the presence of tetrabutylammonium bromide as catalyst. Reaction of 6 with the anion of N‐ethoxycarbonyl‐N′‐methoxy‐N′‐methyl‐L‐alaninamide (4a) gave the chiral (S)‐ketone 8 with ee exceeding 96%. Sodium borohydride reduction of 8, followed by sequential condensation with ethyl 6‐amino‐4‐chloro‐5‐nitro‐2‐pyridine carbamate (11), chromium trioxide oxidation, and catalytic hydrogenation over Raney nickel gave the free base form of [14C]CI‐980 (14a), which was extremely unstable and readily aromatized to 15. The free base 14a was, however, isolated under specially developed conditions and converted to the crystalline isethionate salt 14b in pure form.
Synthesis of [3H]CI‐980, ethyl[5‐anino‐1,2‐dihydro‐2(S)‐methyl‐3(3‐[3H]phenyl)pyrido[3,4‐b]jpyrazin‐7‐YL] carbamate isethionate salt, a tubulin‐binding, antimitotic, broad‐spectrum antitumor agent
Authors: Lee Helen T. , Woo Peter W. K. 
Published: October 2006

Abstract[3H]CI‐980 (10b) was synthesized in an eight‐step sequence with an overall yield of 2.4%. Reaction of m‐bromophenyl lithium (2) with N‐ethoxycarbonyl‐L‐alanine gave the chiral ketone 3. Reduction of 3 with sodium borohydride followed by alkaline N‐deprotection and condensation with ethyl 6‐amino‐4‐chloro‐5‐nitro‐2‐pyridine carbamate (6) gave 7. Chromium trioxide oxidation of 7 followed by reductive cyclization with iron‐acetic acid gave the key bromo intermediate 9. Palladium catalyzed 3H‐hydrogenolysis of 9 gave the free base form of [3H]CI‐980 (10a), which was converted to the isethionate salt (10b) before use.
Synthesis of 5‐fluoro‐3‐[3‐[4‐(2‐[14C]‐5‐methoxy‐4‐pyrimidinyl)‐1piperazinyljpropypiperazinyl]propyl]‐1H‐indole dihydrochloride
Authors: Haynes Ute J. , Swigor J. E. 
Published: October 2006

AbstractThe synthesis of 5‐Fluoro‐3‐[3‐[4‐(2‐[14C]‐5‐methoxy‐4‐pyrimi‐dinyl)‐1‐piperazinyl]propyl]‐1H‐indole dihydrochloride (5) was achieved by coupling [14C] formamidine acetate (1) and dimethylmethoxymalonate in methanol containing sodium methoxide at 60°C to provide 2‐[14C] 4,6‐dihydroxy‐5‐methoxyprimidine (2). Reaction of (2) with phosphorous oxychloride produced the unstable chloro‐compound (3) which was reacted with 5‐Fluoro‐3‐(3‐N‐piperazinylpropyl) indole to give 5‐Fluoro‐3[3‐[4‐(2‐[14C]‐6‐chloro‐5‐methoxy‐4‐pyrimidinyl)‐1‐piperazinyl] propyl]‐1H‐indole (4). Catalytic reduction of (4) and addition of 2 equivalents of hydrochloric acid resulted in the title compound as the dihydrochloride (5).
Synthesis of 3H‐ and 14C‐labelled CP‐88,059: A potent atypical antipsychotic agent
Authors: Howard Harry R. , Shenk Kevin D. , Smolarek Teresa A. , Marx Michael H. , Windels James H. , Roth Robert W. 
Published: October 2006

AbstractThe syntheses of 3H‐ and 14C‐labelled CP‐88,059 [i.e., 5‐(2‐(4‐(1,2‐benzisothiazol‐3‐yl)piperazinyl)ethyl)‐6‐chloro‐1, 3‐dihydro‐2H‐indol‐2‐one] are described. CP‐88,059 (5b) is a combined D2/5‐HT2 antagonist currently undergoing clinical evaluation as an antipsychotic agent with reduced potential for induction of EPS in schizophrenic patients. Displacement of bromine from the 7‐position of the benzisothiazole moiety, by reductive dehydrogenation with tritium gas and Pd/BaSO4 catalysis, provided 3H‐CP‐88,059 (5c). Incorporation of 14C into the ethylene portion of the molecule was achieved via the Friedel‐Crafts acylation of 6‐chlorooxindole with [2‐14C]‐chloroacetyl chloride, followed by triethylsilane reduction of the aryl carbonyl and coupling with N‐(1,2‐benzisothiazol‐3‐yl)piperazine in refluxing aqueous Na2CO3.
Synthesis of 17O (and 18O) labelled isophosphoramide mustard
Authors: Han Sung Y. , Shulman‐Roskes Ellen M. , Misiura Konrad , Anderson Lawrence W. , Szymajda Edward , Gamcsik Michael P. , Chang Young H. , Ludeman Susan M. 
Published: October 2006

AbstractThe ifosfamide metabolite isophosphoramide mustard (IPM) was synthesized with isotopic enrichment at oxygen. Labelled benzaldehyde was made by exchange with isotopically enriched water (13.4 atom % 170, 25.5 atom % 180) and this was then reduced with sodium borohydride to give labelled benzyl alcohol (72% yield). Triethylamine and labelled benzyl alcohol were added to POCl3/CHCl3 at −23°C. Subsequent addition of 2‐chloroethylamine hydrochloride (2 equiv) and then triethylamine (4.4 equiv) (−15°C) provided 170/180 enriched N,N′‐bs‐(2‐chloroethyl)phosphorodiamidic acid phenylmethyl ester [61%, BzOP(O)(NHCH2CH2Cl)2]. Catalytic (10% Pd/C) hydrogenation of this ester at atmospheric pressure gave IPM (22%). GC/MS was used to determine mole percent enrichments of 9.3% 170 and 17.9% 180 for IPM (single labelling within one molecule).
Synthesis and purification of desmethylzopiclone‐N‐{3‐(4‐hydroxy‐3‐[125I]‐iodophenyl) propionamide}, a prosthetic derivative of zopiclone for use in immunoassay
Authors: Mannaert E. , Daenens P. 
Published: October 2006

AbstractCondensation of [125I]‐Bolton/Hunter reagent with N‐desmethylzopiclone lead to the title compound which was isolated and purified by normal phase HPLC, in combination with gamma counting detection. The introduction of the prosthetic group into the tracer precursor was proven by L‐SIMS.
A facile synthesis of pentadeuterated domiodol (2‐iodomethyl‐4‐hydroxymethyl‐1,3‐dioxolane) from glycerol‐1,1,2,3,3‐d5
Authors: Ferraboschi Patrizia , Grisenti Paride , Santanitllo Enzo 
Published: October 2006

AbstractThe acid catalyzed reaction of glycerol‐d5 with bromoacetaldehyde dimethyl acetal affords the corresponding 2‐bromomethyl‐4‐hydroxymethyl‐1,3‐dioxolane, which was treated with lithium iodide in 2‐butanone to afford the pentadeuterated domiodol 1 in high isotopic purity.
The synthesis of some tritium‐labelled terminators of DNA synthesis
Authors: Sidorov Georgy V. , Myasoedov Nykolai F. , Yasko Maxim V. 
Published: October 2006

Abstract2′,3′‐Dideoxythymidine, 2′,3′‐dideoxyadenosine, 2′,3′‐dideoxycytidine‐5′‐phosphonate, thymidine‐5′‐phosphonate, labelled with tritium in the carbohydrate residue; thymidine‐5′‐methylphosphonate labelled in the methyl of the phosphonate group and 2′,3′‐dideoxyadenosine labelled in the base and/or carbohydrate residue were prepared by hydrogenolysis with tritium gas. The reaction of solid state catalytic hydrogenation was studied and tritium‐labelled azydothymidine, azydothymidine‐5′‐phosphonate, acyclovire, acyclovire‐5′‐phosphonate were synthesized. A number of general approaches to the synthesis of tritium‐labelled terminators of DNA synthesis were formulated.
The solid‐state synthesis of tritium labelled heterocyclic bases
Authors: Sidorov Georgy V. , Myasoedov Nikolai F. 
Published: October 2006

AbstractThe results of a study of. the solid‐state catalytic hydrogenation and the synthesis of tritium labelled native heterocyclic bases are presented. The effect of different palladium catalysts and reaction conditions on yield and molar radioactivity of final compounds was investigated. For some compounds, data on the intramolecular distribution of tritium were obtained by using the isotope exchange reaction and tritium NMR. Tritium labelled purine and pyrimidine bases (25–180 Ci/mmol.) were synthesized.
Synthesis of the 14C‐labelled juvenoid W328
Authors: Elbert Tomas , Havlicek Libor , Wimmer Zdenek , Bubner Marianne 
Published: October 2006

AbstractThe labelled juvenoid 2‐(4‐(2‐(ethoxycarbamatoethoxy)(benzene‐U‐14C)benzyl) ‐1‐cyclohexanone ethylene acetal (8) (W 328) was prepared starting from p‐hydroxy(ring‐U‐14C)benzoic acid (1) by a seven step synthesis in 11% overall yield. The reaction conditions previousiy reported for the „coid”︁ synthesis of the W 328 (8) were modified to suit the small scale preparation.
Radiolabelling optimization of 5‐(4‐[125I]‐iodophenyl)‐2,3 dihydro‐5‐hydroxy‐5H‐imidazo[2,1‐a]isoindole or [125I]‐iodo mazindol : A potential tool for spect explorations
Authors: Galinier E. , Ombetta J. E. , Frangin Y. , Mertens J. , Besnard J. C. , Guilloteau D. 
Published: October 2006

AbstractThe radiolabelling of an iodinated analog of mazindol, 5‐(4‐[125I]‐iodophenyl)‐2,3‐dihydro‐5‐hydroxy‐5H‐imidazo[2,1‐a]isoindole, was performed in order to develop a potential tool for SPECT exploration of the presynaptic dopamine transporter in the human brain. Radiosynthesis was performed by iodide for bromide nucleophilic exchange from a brominated precursor. The reaction was carried out in the presence of the copper I catalyst and reducing and complexing agents. In these radiolabelling conditions, [125I] iodomazindol exhibited a tautomeric equilibrium. Therefore, in order to obtain the best labelling conditions, we studied variables such as copper I catalyst and brominated precursor concentrations, reaction temperature and heating time involved in the reaction.This study of the kinetics could be used as a pattern for the radiosynthesis of other compounds which can be present in a tautomeric equilibrium under particular conditions. Indeed, we describe a convenient procedure to obtain each tautomeric form with high radiochemical purity in optimum radiolabelling conditions.
Stereoselective synthesis of 3‐o‐methyl‐6‐[18F]fluorodopa via fluorodestannylation
Authors: Adam Michael J. , Lu Jianming , Jivan Salma 
Published: October 2006

Abstract3‐O‐Methyl‐6‐[18F]fluorodopa was synthesized in 20% radiochemical yield in 60 min, with a specific activity of 500 mCi/mmol, by the fluorination of a stannylated dopa precursor with [18F]‐acetyl hypofluorite.
Simple synthesis of multiply labelled sodium propionate
Authors: Iida Katsumi , Uegaki Ryuichi , Kajiwara Masahiro 
Published: October 2006

AbstractSodium [3‐13C]‐ and [3‐13CD3]propionate were conveniently synthesized from 2,4,4‐trimethyl‐2‐oxazoline. The numbers and locations of deuterium labels were confirmed by broad‐band deuterium and proton‐decoupled 13C‐nuclear magnetic resonance (13C‐{1H} {D}NMR) spectroscopy and fast atom bombardment mass (FAB‐MS) spectroscopy.
Synthesis of 2H, 3H and 14C labelled Sch 40120
Authors: Hesk D. , Duelfer T. , Hickey S. , Hochman D. , Koharski D. , McNamara P. , Saluja S. 
Published: October 2006

Abstract2H and 3H labelled Sch 40120 were prepared by Pt catalysed exchange with isotopic water. D7‐Sch 40120 was obtained in two exchanges in 53% yield and 3H‐Sch 40120 was prepared by a single exchange at a specific activity of 19.8 Ci/mmole. 14C‐Sch 40120 was prepared in 4 steps from 14C‐m‐chloro aniline in overall 16% radiochemical yield.
Tritiation of organic compounds by polymer‐supported base catalysts
Authors: Brewer J. R. , Jones J. R. , Lawrie K. W. M. , Saunders D. , Simmonds A. 
Published: October 2006

AbstractA range of organic compounds have been tritiated (and in some cases deuteriated) via hydrogen isotope exchange reactions using polymer supported base catalysts. The problem of poor thermal stability of some commercially available anion exchange resins, which limits their use as tritiation catalysts, has been overcome by the preparation of a more stable polymer supported pyridinium salt. The anion exchange resins are as effective at very high activities of tritiated water as they are at low and compounds containing nitro groups, which poison metal‐catalysed exchange reactions, can be successfully labelled.
Labelling of brefeldin‐a by catalyzed isotopic exchange with tritium gas
Authors: Maetz Ph. , Sobrio F. , Mioskowski C. , Rousseau B. 
Published: October 2006

AbstractThe hydrogen isotope exchange of Brefeldin‐A with tritium gas (T2) in 1,4‐dioxane was studied over a commercial palladium catalyst supported on diatomaceous earth (5% metallic weight). The effect of the gas phase was studied. Addition of air in the gas phase led to an increase of the catalytic activity. Moreover, exchange was enhanced when the air/T2 ratio reached a value of 4. This latter result is interpreted, principally, in terms of a strongly poisoning of the metallic particles together with an effect of the T2 partial pressure. Through the comparison with Pd(II) oxide, the role of the support is also shown. The specific activities ranged up to 2.8 Ci/mMoles. The labelled product was analyzed by 3H NMR. Possible mechanisms for tritium incorporation are discussed and two different adsorbed species, on the catalyst surface, are involved.
A novel synthesis of carbon‐labelled quinolone‐3‐carboxylic acid antibacterials
Authors: Carr Richard M. , Sutherland Derek R. 
Published: October 2006

Abstract3‐lodoquinolones were prepared from the corresponding quinolone‐3‐carboxylic acids by Hunsdiecker‐type iododecarboxylation reactions with lead tetraacetate and iodine. Cyanation of the iodo compounds with mixtures of potassium [13C]cyanide and copper (I) iodide, gave [3‐13C]cyanoquinolones which on acidic hydrolysis afforded quinolone‐[3‐13C]carboxylic acids. In this way, nalidixic acid, an immediate precursor of norfloxacin, and quinolone WIN57273 were labelled with carbon‐13 in the metabolically stable carboxylic acid fragment.
Synthesis and stability of [1,3‐14C2]‐glyceryl trinitrate
Authors: Szammer J. , Simon‐Trompler E. , Máté J. , Abermann M. , Klebovich I. 
Published: October 2006

AbstractThe synthesis of [1,3‐14C2]‐glyceryl trinitrate (14C]‐GTN) labelled with quasi carrier free carbon‐14 atom in the 1,3‐positions of the molecule was effected in four reaction steps from 14CO2 (3,5 % overall yield). The chemical and radiochemical purity of [14C]‐GTN was found better than 99% controlled by HPLC‐Radioactivity Monitor and TLC‐Digital Autoradiograph methods. Study of the radiochemical stability in dilute solution at 5 °C shows that the product can be stored at least for a month without detectable decomposition.
Preparation of [3H]‐labelled benzphetamine photoaffinity probes for cytochrome P‐450
Authors: Hodek Petr , Strobel Henry W. 
Published: October 2006

AbstractWe have synthesized two tritium labelled photolabile azid‐α‐desmethylbenzphetamine analogues: N‐benzyl‐N‐methyl‐p‐azido‐phenethylamine ([3H]BP‐N3) and N‐(p‐azidobenzyl)‐N‐methyl‐p‐azido‐phenethylamine ([3H]N3‐BP‐N3). These compounds, photoaffinity probes for cytochrome P450 2B1, were prepared in a two step synthetic process. First, the iodinated aminoderivative precursors N‐benzyl‐N‐methyl‐4‐amino‐3,5‐diiodophenethylamine and N‐(4‐amino‐3,5‐diiodobenzyl)‐N‐methyl‐4‐amino‐3,5‐diiodophenethylamine were subjected to reductive deiodination on a Pd/C catalyst using sodium [3H]borohydride as an in situ generator of tritium gas. Second, resultant radiolabelled amino‐compounds were converted into the final [3H]BP‐N3 and [3H]N3‐BP‐N3 compound through their diazoderivatives without separation of their intermediates.