bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of novel tritium labeled oxamyristic acids
Authors: Devadas Balekudru , Adams Steven P. , Gordon Jeffrey I. 
Published: October 2006

AbstractSyntheses of [3H]‐labeled 13‐oxa (5) and 6‐oxa (9) myristic acids with specific activity of 137 Ci/mmol and 105 Ci/mmol respectively, starting from the corresponding acetylenic precursors, 12‐methoxy‐10‐dodecynoic acid (4) and 5‐(3‐octynyloxy)pentanoic acid (8) are described. The precursor 4 is readily obtained in high yield by alkylation of the lithium salt of methyl propargyl ether with 9‐iodononanoic acid, whereas 8 is obtained by alkylation of 3‐octyn‐1‐ol with t‐butyl‐5‐bromovalerate under phase transfer conditions, followed by acid catalysed removal of the t‐butyl group.
Synthesis of two 14C‐labelled catechol‐O‐methyltransferase inhibitors
Authors: Karlsson Carita , Honkanen Erkki 
Published: October 2006

Abstract14C‐labelled 3‐(3, 4‐dihydroxy‐5‐nitrophenylmethylidene)‐2,4‐pentanedione (4) and 14C‐labelled E‐N, N‐diethyl‐2‐cyano‐3‐(3,4‐dihydroxy‐ 5‐nitrophenyl)acrylamide (5) have been synthesized from [carbonyl‐14C]vanillin.
A convenient synthesis of 14C‐cotinine from 14C‐nicotine
Authors: Desai Dhimant H. , Djordjevic Mirjana V. , Amin Shantu 
Published: October 2006

AbstractA convenient synthesis with analytical monitoring of 14C‐cotinine is reported. 14C‐Nicotine was converted into 14C‐dibromocotinine hydrobromide perbromide. Debromination, achieved by using Zn dust/acetic acid, resulted in high yields (71%) of 14C‐cotinine.
Synthesis of 3,5‐diisopropyl[carboxy‐14C]salicylic acid and its 67CU complex
Authors: Chidambaram Mankulathu V. , Epperson Claude E. , Williams Skip , Gray Ronda A. , Sorenson John R. J. 
Published: October 2006

AbstractThe synthesis of 3,5‐diisopropyl[carboxy‐14C]salicylic acid was achieved via Kolbe‐Schmitt carboxylation of potassium 2,4‐diisopropylphenolate. The yield of this acid was 81% based upon the weight of the product and 93% based upon radioactivity incorporated into the labeled acid which contains 98% 14C in the carboxyl group (specific activity = 5.1 μCi/mg). The labeled acid was characterized by ultraviolet spectrophotometry and purity established by thin‐layer chromatography, autoradiography, and liquid scintillation counting. A 90% yield of the double labeled 14C, 67Cu‐complex (specific activity = 4.6 μC/mg) was obtained using conditions developed with non‐radioactive reactants. The presence of 67Cu in this complex was established using γ‐ray emission spectrophometry.
Specific tritium labelling of sphingosines at the 3‐position
Authors: Birk Rolf , Brenner–Weiß Gerald , Giannis Atanassios , Sandhoff Konrad , Schmidt Richard R. 
Published: October 2006

AbstractAzidosphingosines 4A,B are transformed with DDQ into the corresponding keto derivatives 6A,B. Reduction of the keto group with [3H]NaBH4 and then conversion of the azido group into the amino group by Staudinger reaction yields stereoselectively the D‐erythro‐and L‐threo‐sphingosines 9A,B, 10A,B, respectively.
Synthesis of the enantiomers of 3‐deuterium labelled lactic acid
Authors: Sanière Michèle , Hafa Hassane El , le Merrer Yves , Depezay Jean Claude , Rocchiccioli Francis 
Published: October 2006

AbstractBoth R‐ and S‐ enantiomers of 3‐monodeuterated lactic acid ([3‐2H]‐2(R) and 2(S)‐hydroxypropanoic acids) were synthesized by regiospecific nucleophilic opening of diastereoisomer epoxides derived from D‐mannitol, with lithium aluminium deuteride. Spectroscopic analysis of the product shows a complete deutero‐incorporation which makes [3‐2H]‐lactic acid suitable as an internal standard using gas chromatography‐mass spectroscopy.
Synthesis of deuterium labelled cocaine and pseudococaine
Authors: Casale J. F. , Lewin A. H. , Raney H. T. , Cooper D. A. 
Published: October 2006

AbstractCocaine and pseudococaine were mass‐labelled with deuterium at various positions on the tropane ring. The synthetic procedures followed were adaptations of those previously published for the unlabelled compounds. The isotopic purity was greater than 95% for 2‐[2H]–, 4,4‐[2H2]‐, and 1,5,6,6,7,7‐[2H6]‐cocaine and 3‐ [2H]‐, 4,4‐[2H2]‐, and 1,5,6,6,7,7‐[2H6]‐pseudococaine, while that of 3‐[2H]‐cocaine exceeded 90%.
Synthesis and characterization of optically pure [3H](+)azidophenazocine ([3H](+)‐AZPH), a novel photoaffinity label for sigma receptors
Authors: de Costa Brian R. , Bowen Wayne D. 
Published: October 2006

Abstract[3H](+)‐cis‐N‐(2‐(4‐Azidophenyl)ethyl) ‐2′‐hydroxy‐2,6‐dimethyl‐6,7‐benzomorphan ([3H]1) ([3H](+)‐AZPH), a novel high affinity and high selectivity benzomorphan based photoaffinity label for sigma receptors was synthesized in 4 steps starting with optically pure (+)‐normetazocine and 2‐(p‐azidophenyl)ethyl methanesulfonate ester. Condensation of these compounds in DMF in the presence of NaHCO3 afforded 1 in 77% yield. The tritiation precursor (+)‐cis‐N‐(2‐(4‐azidophenyl)ethyl)‐2′‐hydroxy‐1′,3′‐dibromo‐2,6‐dimethyl‐6,7‐ benzomorphan (4) for medium specific activity [3H]1 was obtained in 96% yield by bromination of 1 with 2 equivalents of bromine. The sequence of catalytic tritiation of 4, treatment of the resulting aniline ([3H]5) (13.5% radiochemical yield, specific activity 22.9 Ci/mmol) with nitrous acid followed by sodium azide afforded the target compound in 78% chemical yield.
Synthesis of [2‐14C]‐2′‐deoxycytidine‐3N‐cyanoborane
Authors: Burnham Bruce S. , Wyrick Steven D. , Hall Iris H. , Sood Anup , Spielvogel Bernard F. 
Published: October 2006

AbstractSynthetic nucleosides (e.g., 5‐fluorouracil, 6‐mercaptopurine) are used extensively as antineoplastic drugs. Recent research in boron chemistry has lead to the development of a series of amine‐boranes that possess significant antineoplastic activity. The agents may also be useful in boron neutron capture therapy (BNCT), therefore giving the compounds a dual mechanism of cytotoxic action. Herein is a report of the synthesis of one of the more active boronated nucleosides, 2′‐deoxycytidine‐3N‐cyanoborane with a 14C‐label in the 2‐position of the pyrimidine ring.
Syntheses of tritium and carbon‐14 labelled N‐ (3‐dimethyl aminopropyl) ‐N‐(ethylaminocarbonyl)‐6‐(2‐propenyl)ergoline‐8β‐carboxamide (cabergoline), a potent long lasting prolactin lowering agent
Authors: Mantegani Sergio , Brambilla Enzo , Ermoli Antonella , Fontana Erminia , Angiuli Patrizia , Vicario Gian Piero 
Published: October 2006

AbstractThe syntheses of 3H‐ and 14C‐labelled cabergoline (FCE 21336), namely N‐(3‐dimethylaminopropyl)‐N‐(ethylamino‐carbonyl)‐6‐(2‐propenyl)ergoline‐8 β ‐carboxamide 1 and its analogues are described.Tritiated cabergoline ([3H]cabergoline) 6, namely N‐(3‐dimethylaminopropyl)‐N‐(ethylaminocarbonyl)‐6‐(2‐ [2,3‐3H]‐propenyl)ergoline‐8β‐carboxamide, was obtained, by catalytic reduction with tritium gas, according to two different synthetic procedures:

‐ a three step route, starting from 6‐(2‐propargyl)‐dihydro lysergic acid‐methyl ester 3 gave [3H]cabergoline, 97% radiochemically pure, with a specific radioactivity of 11.19 GBq/mmol and in an overall radiochemical yield of 3.5%.
‐ a one step route, starting from 1‐ethyl‐3‐(3‐dimethyl‐aminopropyl)‐3‐6′‐(2‐propargyl)ergoline‐8′β‐ carbonyflurea 5′ yielded [3H]cabergoline with a radiochemical purity >97%, specific radioactivity 1.06 TBq/mmol and radiochemical yield of 23%.
A modification of this last procedure also gave [3H]dihydro cabergoline ([3H]FCE 23411), namely N‐(3‐dimethylaminopropyl) ‐N‐(ethylaminocarbonyl)‐6‐(2‐[2,3‐3H]propyl)ergoline‐8β‐carboxamide 7, 97% radiochemically pure and with a specific radioactivity up to 4.03 TBq/mmol.The synthesis of [14C]cabergoline was carried out, in a three step route, by addition of potassium[14C]cyanide to 6‐(2‐propenyl)‐8β‐chloroergoline 12 to give the expected N‐(dimethylaminopropyl)‐N‐(ethylaminocarbonyl)‐6‐(2‐propenyl)‐ergoline‐8β‐ [14C]carboxamide 15′, 97% radiochemically pure with a specific radioactivity of 2.09 GBq/mmol and an overall radiochemical yield of 16%.
Synthesis of [10,10,10‐2H3]geranyl diphosphate
Authors: Izumi Shunsuke , Aihara Mie , Hiraga Yoshikazu , Hirata Toshifumi , Suga Takayuki 
Published: October 2006

Abstract[10,10,10‐2H3]‐3, 7‐Dimethyl‐2(E), 6‐octadienyl diphosphate ([10,10,10‐2H3]geranyl diphosphate) was synthesized from 6‐(benzyloxy)‐4‐methyl‐4(E)‐hexenal by regioselective deuteration involving a modified Wittig reaction as the key step.
Synthesis of 14C or 3H‐labelled indometacin farnesil (E‐0710)
Authors: Abe Shinya , Yamatsu Isao , Yamato Chihiro , Kobayashi Seiichi , Mishima Mannen 
Published: October 2006

AbstractA 14C or 3H‐labelled, 7:3 (2E:2Z) isomeric mixture of 6E‐3, 7, 11‐trimethyl‐2, 6, 10‐dodecatrienyl‐1‐(p‐chlorobenzoyl)‐5‐methoxy‐2‐methyl‐1H‐indole‐3‐acetate (indometacin farnesil; IMF), a prodrug of indomethacin, was synthesized in order to study the pharmacokinetic profiles of this drug. Esterification of a 7:3 (2E:2Z) isomeric mixture of 6E‐3, 7, 11‐trimethyl‐2, 6, 10‐dodecatrienol [farnesol (3)] with [2‐14C] indomethacin [14C‐IND (1)] or [G‐3H] indomethacin [3H‐IND (2)] gave the corresponding 14C or 3H‐labelled indometacin farnesil [14C‐IMF (4) or 3H‐IMF (5)]. On the otherhand, [3‐14C] 6E‐3, 7, 11‐trimethyl‐2, 6, 10‐dodecatrienol [14C‐F (8)] which was obtained from [2‐14C] 5E‐6, 10‐dimethylundeca‐5, 9‐dien‐2‐one [14C‐geranyl acetone (7)] in two steps, was esterified with indomethacin to give farnesyl moiety 14C‐labelled indometacin farnesil 14C‐F‐IMF (6) 1.
The synthesis of (5R)‐ and (5S)‐[5‐3H]‐L‐ornithine
Authors: Parry Ronald J. , Ju Shyhchen , Baker Bill J. 
Published: October 2006

AbstractA practical synthesis of (5R)‐ and (5S)‐[5‐3H]‐L‐ornithine is described. The key steps in the synthesis are the reduction of [formyl‐3H]‐5‐hexenal with S‐ or R‐Alpine Borane to (1R)‐ and (1S)‐ [1‐3H]‐5‐hexen‐1‐ol and the use of the Evans electrophilic azidation of chiral imide enolates to introduce the α‐amino group of ornithine. The stereochemistry expected for the Alpine Borane reduction was verified by NMR analysis of the camphanate ester derived from reduction of [formyl‐2H]‐5‐hexenal with R‐Alpine Borane.
A short synthesis and its application to the preparation of radio labelled leukotriene inhibitor Sch 37224
Authors: Duelfer T. , Gala D. 
Published: October 2006

AbstractA new, short synthesis of 1‐(1,2‐dihydro‐4‐hydroxy‐1‐phenyl‐2‐oxo‐1,8‐naphthyridin‐3‐yl)‐pyrrolidinium hydroxide, inner salt, 1, was achieved by condensing methyl 2‐phenylamino‐3‐pyridine carboxylate 2 with ethyl 1‐pyrrolidine acetate 4. This gave highly pure product in 60% yield. This synthesis was applied to the preparation of 14C labelled 1. Radiolabelled 1 was synthesized from u‐[14C]‐aniline in three steps at 97% radiochemical purity and 27.3% radiochemical yield.
Synthesis of (Z)‐3‐[4‐(acetyloxy)‐5‐ethyl‐3‐methoxy‐1‐NAPH‐thalenyl]‐2‐methyl‐2‐ propenoic‐2‐14C acid (14C‐E5090)
Authors: Tanaka Masayuki , Sakurai Hideki , Yoshimura Tsutomu 
Published: October 2006

Abstract(Z)‐3‐[4‐(Acetyloxy)‐5‐ethyl‐3‐methoxy‐1‐naphthalenyl]‐2‐methyl‐2‐propenoic‐2‐14C acid 7 (14C‐E5090) was synthesized in order to study the pharmacokinetic profile of E5090, an orally active inhibitor of IL‐1 generation. 14C‐E5090 with a specific activity of 43.34mCi/mmol was prepared in 5 steps in 12.9% overall yield from 5‐ethyl‐3‐methoxy‐4‐methoxymethoxy‐1‐naphthalenecarbaldehyde 1.
Synthesis of [14C]‐labelled eicosa‐5,8,11‐triynoic acid and conversion to anti‐inflammatory amides
Authors: Pilgrim W. R. , Nedoncelle P. , Shroot B. , Maignan J. , Restlé S. , L'Oréal  
Published: October 2006

AbstractA four step synthesis of [5,6‐14C]‐eicosa‐5,8,11‐triynoic acid (1) from [14C]‐labelled acetylene is described. [14C2]‐acetylene was converted to 5‐chloro‐[1,2‐14C]‐pentyne via reaction of its monolithium salt with 3‐bromo‐1‐chloropropane. The doubly labelled 5‐chloropentyne thus obtained was transformed to [5,6‐14C]‐hex‐5‐ynoic acid which was then coupled with 1‐chloro‐tetradeca‐2,5‐diyne to give the title compound. Using 2‐(2‐aminoethoxy)ethanol and 1‐(2‐hydroxyethyl)piperazine, amides (2) and (3), which had previously been found to be potent inhibitors of the 5‐lipoxygenase enzyme, were prepared from [14C]‐labelled eicosatriynoic acid by way of acylimidazole chemistry.
Synthesis of tritium labelled 5,6‐dihydro‐7‐(1H‐imidazol‐1‐YL)‐naphthalene‐2‐carboxylic acid (FCE 22178), a new thromboxane synthetase inhibitor
Authors: Fontana Erminia , Vicario Gian Piero 
Published: October 2006

AbstractSynthesis of [3H]FCE 22178, namely 5,6‐dihydro‐7‐(1H‐[G‐3H]imidazol‐1‐yl)‐naphthalene‐2‐carboxylic acid 5 was performed in three steps from 5,6,7,8‐tetrahydro‐8‐hydroxy‐7‐(1H‐imidazol‐1‐yl)‐naphtalene‐2‐carboxylic acid 2 by bromination, catalytic tritiation and final dehydration, in an overall radiochemical yield of 48%. The product was 97% radiochemically pure and had a specific radioactivity of 9.15 GBq/mmol.
Synthesis of tritium labeled MK‐886, a leukotriene biosynthesis inhibitor; employment of epibromohydrin as a masked electrophilic acetone synthon
Authors: Schmidt Stanley J. , Garnes Keith T. , Heys J. Richard , Landvatter Scott W. , Adams Jerry L. 
Published: October 2006

Abstract1‐(4‐Chloro‐[3‐3H]benzyl) ‐3‐(t‐butylthio)‐a, a‐dimethyl‐5‐(i‐propyl) ‐indole‐2‐propanoic acid (10, MK‐886) was prepared by catalytic tritium/halogen exchange on 1‐(4‐chloro‐3‐iodobenzyl)‐3‐(t‐butylthio)‐a,a ‐dimethyl‐5‐(i‐propyl)‐indole‐2‐propanoic acid (9). Compound 9 was prepared by a synthesis converging at the indole benzylation step. The required indole 4 was prepared by means of a Fischer indole synthesis employing the highly functionalized unsymmetrical ketone 3. Ketone 3 was efficiently made in three steps using epibromohydrin as a masked electrophilic acetone synthon. The halogenated benzyl bromide moiety 7 was prepared in three steps from 1‐chloro‐2‐iodo‐4‐(trifluoromethyl)‐benzene.
An expedient synthesis of high specific activity tritium labelled 4‐fluoro‐1‐[1‐(2‐thienyl)]cyclohexylpiperidine ([3H]FTCP), a ligand for further characterization of the phencyclidine/NMDA receptor complex
Authors: Grayson Neile A. , de Costa Brian R. , Linders Joannes T. M. , Rice Kenner C. 
Published: October 2006

Abstract[18F]4‐Fluoro‐1‐[1‐(2‐thienyl)cyclohexyl)]piperidine is a ligand potentially useful for positron emission tomography of the PCP/NMDA receptor complex in the mammalian brain. The tritium‐labelled title compound was synthesized in 5 steps starting with cyclohexanone. Catalytic tritiolysis in the final step afforded the title compound in high radiochemical yield and specific activity. This method represents a more efficient approach than previously published syntheses.
Syntheses of 3H‐ and 2H‐labeled (17R)‐17,20‐dimethyl‐7‐thiaprostaglandin E1 methyl ester
Authors: Tanaka Toshio , Bannai Kiyoshi , Manabe Kenji , Kurozumi Seizi 
Published: October 2006

AbstractThe syntheses of [19,20‐3H2]‐ and [3,3,4,4,5,5,6,6‐2H8]‐(17R)‐ 17,20‐dimethyl‐7‐thiaprostaglandin E1 methyl esters (3 and 5) are described. The di‐tritiated compound 3 was prepared from its protected (Z)‐Δ 19‐precursor (21) via catalytic reduction with tritium gas having a specific activity of 49 Ci / mmol. The octa‐deuterated compound 5 was prepared from tetrahydrofuran‐d8.
Synthesis of S‐ribosyl‐L‐homocysteine specifically tritiated at the 5‐C position
Authors: Guillerm G. , Allart B. 
Published: October 2006

AbstractS‐Ribosyl‐L‐homocysteine, tritiated specifically at the 5‐C position, has been synthesized in order to assay S‐Ribosyl‐L‐homocysteine hydrolase (EC. 3.3.1.3).
14C‐labeling of a novel carbapenem antibiotic SM‐7338
Authors: Nishioka Kazuhiko , Kanamaru Hiroshi 
Published: October 2006

Abstract(1R,5S,6S)‐2‐ [(3S,5S)‐5‐Dimethylaminocarbonylpyrrolidin‐3‐ylthio]‐6‐ [(1R)‐1‐hydroxyethyl]‐1‐methylcarbapen‐2‐em‐3‐carboxylic acid trihydrate (SM‐7338), a novel 1 β‐methyl carbapenem antibiotic, was labeled with carbon‐14 at the C3 position of the carbapenem nucleus for use in metabolic studies. The synthesis was achieved according to the scheme illustrated in Fig. 3. Selective esterification of [2‐14C]malonic acid (2) with 4‐nitrobenzyl bromide (3) gave its monoester (4). Condensation of the magnesium salt of 4 with the imidazolide derived from the azetidinone carboxylic acid (5) provided the β‐keto ester (6), which was desililated with hydrochloric acid to give the alcohol (7). Treatment of 7 with carboxybenzenesulfonyl azide followed by decomposition of the resulting diazo intermediate (8) in the presence of a rhodium catalyst produced the bicyclic keto ester (9). Reaction of 9 with diphenyl chlorophosphate in the presence of N,N‐diisopropylethylamine and subsequent displacement reaction of the vinyl phosphate (10) with mercaptopyrrolidine (11) gave bis‐protected SM‐7338 (12). Catalytic hydrogenolysis of 12 afforded [carbapenem‐3‐14C]‐SM‐7338 (1). The overall yield of 1 was 5.8% from 2.
Chiral synthesis of L‐[14C]phenylalanine and its incorporation into the renin inhibitor PD 132002
Authors: Lee Helen T. , Hicks James L. , Johnson Donald R. 
Published: October 2006

Abstract[1S‐(1R*,2S*,3R*)]‐3‐[[1‐(Cyclohexylmethyl)‐2,3‐dihydroxy‐5‐methylhexyl]‐amino]‐N‐[N‐(4‐morpholinosulfonyl)‐L‐ phenylalanyl]‐3‐oxo‐DL‐alanine methyl ester (PD 132002) was found to be a renin inhibitor and thus potentially useful for the treatment of hypertension. This peptidomimetic agent contains an L‐phenylalanine residue which was chosen as the site for carbon‐14 incorporation. The chiral synthesis using (4S)‐4‐(phenylmethyl)‐2‐oxazolidinone as a chiral auxiliary for asymmetric hydrazide formation was modified to make it amenable to carbon‐14 synthesis.L‐[1‐14C]Phenylalanine was synthesized in seven steps from 14CO2 in an overall yield of 33%. It was further converted to [14C]PD 132002 in three more steps with an overall yield of 4.95%. The final specific activity was 35.5 mCi/mmol.
Synthesis of tritium labelled TRH‐like peptides using asymmetric anhydride coupling
Authors: Bílek R. , Bradbury A. F. , Smyth D. G. 
Published: October 2006

AbstractA method is presented for the preparation of [3H]‐labelled TRH‐like tripeptides. The synthesis involves preparation of the appropriate dipeptide by the solid phase procedure using Fmoc‐protection and the [3H]‐labelled pyroglutamic acid is then coupled as a mixed anhydride with Fmoc‐phenylalanine. Conditions suitable for the conversion of [3H]‐glutamine to [3H]‐pyroglutamic acid are also described. The [3H]‐labelled tripeptides are obtained in a high state of purity and with efficient incorporation of radiolabel.
An improved synthetic procedure for the preparation of 195mPt labelled anti‐tumour complexes
Authors: Jackson H. , McAuliffe C. A. , Perera A. , Sharma H. L. , Tinker N. J. 
Published: October 2006

AbstractAn improved synthetic procedure for the preparation of high specific activity 195mPt labelled cisplatin, carboplatin and iproplatin is reported. The procedure involves synthetic strategies which optimise the yields at each stage of the synthesis, giving products of high purity and in high yield (ie. cisplatin and carboplatin, 43%, and iproplatin, 22%). A new procedure for the synthesis of carboplatin using silver 1,1‐cyclobutanedicarboxylate is also reported.
Synthesis of labeled (10R)‐Juvenile hormone III bisepoxide, and its photoaffinity analog, [12‐3H]‐(10R)‐6,7,10,11‐bisepoxyfarnesyl diazoacetate (BEFDA)
Authors: Latli Bachir , Prestwich Glenn D. 
Published: October 2006

AbstractRadiolabeled optically‐active JH III bisepoxide ([3H]‐(10R)‐JHB3) was synthesized from [12‐3H] (10R)‐JH III using dimethyldioxirane to give an inseparable mixture of diastereomers with the trans‐6,7‐epoxide syn or anti to the existing 10,11‐epoxide. [3H]‐(10R)‐JHB3 (or the unlabeled material) was converted in three steps to the corresponding (10R)‐6,7,10,11‐bisepoxyfarnesyl diazoacetate (BEFDA), a photoaffinity label for JHB3 receptors and binding proteins.
Synthesis of tritium labeled musk xylene, [3H] 5‐tert‐butyl‐2,4,6‐trinitro‐m‐xylene
Authors: Fukuoka Masamichi , Nambaru Seiichi , Tanaka Akira 
Published: October 2006

AbstractSynthesis of 3H‐musk xylene (MX) was carried out by two schemes. Nitration of 3H‐5‐tert‐butyl‐m‐xylene (3) decreased in the 3H‐incorporation ratio. Reduction of MX‐bromide (6) with NaB3H4 gave the highly labeled MX (8) and another bromide (7) gave 9 with tritium atom produced by equilibration between NaB3H4 and H2O or between NaBH4 and 3H2O.
Use of 2‐dimethylaminopyridine in tritium and deuterium exchange reactions
Authors: Reddy Guvvala N. , Soares Christopher J. , Kurth Mark J. , Segall Hank J. 
Published: October 2006

AbstractAdvantages of 2‐dimethylaminopyridine as base in isotope exchange reactions that occur via enol formation are described for the preparation of deuterium and tritium labeled hexanal.
A simple synthesis of [1,3‐13C2]4‐(2,6,6‐trimethylcyclohexen‐1‐yl)buten‐2‐one (ß‐ionone)
Authors: Curley Robert W. , Blust Michael A. , Humphries Keith A. 
Published: October 2006

AbstractA convenient, one‐step synthesis of doubly 13C‐labelled ß‐ionone was accomplished by aqueous sodium hydroxide catalyzed aldol condensation of 1,3‐13C2‐acetone with the recently commercially available ß‐cyclocitral. This retinol‐like compound obtained in ca. 60% yield, should prove useful in NMR studies of retinoid binding to its transport proteins.
Tritium labelling of polyols
Authors: Akulov G. P. , Snetkova E. V. , Kaminski Ju. L. , Kudelin B. K. , Efimova V. L. 
Published: October 2006

AbstractMannitol, galactitol and myo‐inositol were labelled by a solid state isotope exchange with gaseous tritium. The labelled polyois were prepared with specific activities in the range 740–4440 TBq/mol (20–120 kCi/mol) after purification by HPLC.
The synthesis of tritium‐labelled alanine by solid‐state catalytic reactions
Authors: Yu. A. Zolotarev , Kozik V. S. , Dorokhova E. M. , Tatur V. Yu. , Rosenberg S. G. , Myasoedov N. F. 
Published: October 2006

AbstractThe solid‐state catalytic hydrogenation (SCH) of unsaturated precursor compound and the high‐temperature solid‐state catalytic isotope exchange (HSCIE) showed that the total incorporation of isotope and its distribution between the α‐and β‐positions of the alanine molecule can be modified by changing the temperature of solid state reactions. Tritium incorporation at high‐temperatures proceeds in a manner which retains the configuration of the asymmetric α‐carbone atom. 3H NMR analysis of tritiated isotopomers was used for the investigation of solid‐state reactions. The HSCIE reaction proceeds selectively at 140 °C and only part of the molecules is in the the tritium spillover reaction zone. At 220°C HSCIE proceeds evenly along the whole mass to give uniformly labelled alanine.
Synthesis of the cardiotonic agent 14C‐loprinone.
Authors: Yamanaka Motosuke , Suda Shinji , Tadano Kyoichi 
Published: October 2006

Abstract14C‐Labeled 1,2‐dihydro‐5‐imidazo [1,2‐a]pyridin‐6‐yl‐6‐methyl‐2‐oxo‐3‐pyridinecarbonitrile hydrochloride monohydrate 6 was synthesized in 5 steps from 6‐bromoimidazo [1,2‐a] pyridine using [2‐14C] cyanoacetamide as the source of the radiolabel. The key intermediate, 1‐imidazo [1,2‐a] pyridin‐6‐yl‐2‐propanone 3 was prepared by the selective ozonolysis of the propenyl group of 6‐(2‐methylpropen‐3‐yl) imidazo [1,2‐a] pyridine 2 under acidic conditions followed by the reduction with sodium sulfite. The chemical yield of 6 from 4‐dimethylamino‐3‐imidazo‐[1,2‐a]pyridin‐6‐yl‐3‐buten‐2‐one 4 and the radiochemical yield from [2‐14C] cyanoacetamide were both 57%. The radiochemical purity and the specific activity of 6 were 98% and 1868.5 MBq/mmol, respectively.
Synthesis of (±)‐[1,1′‐15N2, 2′‐13C]‐trans‐3′‐methylnicotine
Authors: Sirimanne Sarath R. , Maggio Vincent L. , Patterson Donald G. 
Published: October 2006

AbstractThe synthesis of (±)‐[1,1′‐15N2, 2′‐13C]‐trans‐3′‐methylnicotine is reported.15N‐3‐Bromopyridine obtained from bromination of pyridine was formulated with nBuLi/[carbonyl‐13C]‐methyl formate. The resulting15N‐Pyridine‐3‐[13C‐carbonyl]‐carboxaldehyde was reacted with15N‐methylamine and then the resulting Schiff's base was condensed with succinic anhydride to give (±)‐[1,1′‐15N2, 5′‐13C]‐trans‐4′‐carboxycotinine. Reduction with lithium aluminium hydride and mesylation followed by reduction with Zn/Nal gave (±)‐[1,1′‐15N2, 2′‐13C]‐trans‐3′‐methylnicotine.