bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation of 2‐[125I] iodohistamine‐labelled Δ8‐tetrahydrocannabinol‐11‐oic acid for use in cannabinoid radioimmunoassay
Authors: Law B , Mason P A , Moffat A C , King L J 
Published: October 2006

AbstractA simple method is described for the preparation of 2‐[125I]iodohistamine‐labelled Δ8‐tetrahydrocannabinol‐11‐oic acid with high specific activity for use in radioimmunoassay. This compound is produced in high yield and shows excellent radiochemical stability when stored at 4°C. The radiolabelled cannabinoid has been shown to bind avidly to four different broadly specific cannabinoid antisera. It is the only [125I] labelled cannabinoid suitable for use in radioimmunoassay with such antisera.
A procedure for the radioiodination of a ganglioside derivative
Authors: Klemm Nancy , Su Song‐Nan , Harnacker Barbara , Jeng Ingming 
Published: October 2006

AbstractA procedure for the preparation of a radioiodinated derivative of ganglioside GM1 has been devised. Carbon 6 of the terminal galactosyl residue of GM1 was converted to an aldehyde by galactose oxidase. The adduct formed by this oxidation product of GM1 with tyramine was reduced with sodium cyanoborohydride. The tyramine moiety covalently attached to GM1 was then labelled by the conventional iodine chloride procedure. The technique described herein is simple and economical for the preparation of a highly radioactive GM1 derivative.
Preparation of 4‐iodo‐2‐methyl‐1‐butene‐1,1‐d2
Authors: Wolff Steven , Agosta William C. 
Published: October 2006

AbstractA nine‐step preparation of 4‐iodo‐2‐methyl‐1‐butene‐1,1‐d2 (9) from 2‐methylbutyrolactone (1) is described.
Synthèese De Molécules Amphiphiles Marquées Aux Isotopes Stables 13C et 15N
Authors: Bouloussa O. , Dizabo P. 
Published: October 2006

AbstractPartant de Ba13CO3, K13CN ou de phtalimide, nous décrivons la synthèse et la purification d'acides gras, d'amines grasses et de N acyl amino acides marqués spécifiquement au 13C ainsi que d'amines grasses marquées à l'azote 15. L'identification et la pureté de ces composés ont été effectuées par SM et RMN 13C.
Synthese von [2′‐14C] 8‐Methoxypsoralen
Authors: Zipp H. , Zimmer A. , Koss F. W. 
Published: October 2006

AbstractDie Synthese von 14C‐Ring‐markiertem 8‐Methoxypsoralen (MELADININE) wird beschrieben. Auf die säulenchromatographische Reinigung der einzelnen Produkte sowie auf die radiodünnschichtchromatographische Reinheit und Identitätskontrolle besonders des Endproduktes wird eingegangen. Ausgehend von (2‐14C)‐Chloressigsäure und Pyrogallol werden 860 mg (4 mMol) (2′‐14C)‐8‐Methoxypsoralen mit einer spezifischen Radioaktivität von 1,3 mCi/mMol, [6,0 μCi/mg; 2,2 × 105 Bq/mg] in einer 8‐Stufen‐Synthese hergestellt. Die Ausbeute, präparativ und radiochemisch, beträgt 16 % d. Th.
Synthesis of n‐octyltrichlorosilane labeled with 13C in the terminal position
Authors: Gangoda M. E. , Gilpin R. K. 
Published: October 2006

AbstractThis report describes the synthesis of carbon‐13 labeled n‐octyltrichloro silane from 13C‐barium carbonate. The product is labeled at the 8‐position of the alkyl chain.
Preparation of methyl [1‐14C]docosa‐7,10,13,16‐tetraenoate
Authors: Neergaard Jon R. , Coniglio John G. , Smith Howard E. 
Published: October 2006

AbstractMethyl [1‐14C]docosa‐7,10,13,16‐tetraenoate was prepared from [1‐14C]arachidonic acid by two successive Arndt‐Eistert syntheses which also can be used for the step‐wise homologation of other labeled fatty acids. After purification by gas chromatography the specific activity was 6.16 mCi/mmol, and the radiochemical purity was 97%.
The synthesis of 4‐d2, 5‐d2 and 4,5‐d4‐2‐dicyclopropylmethylamino‐Δ2‐oxazolines
Authors: Ehrhardt J. D. 
Published: October 2006

AbstractThe synthesis of deuterated ethanolamines and deuterated 2‐dicyclopropylmethylamine‐Δ2‐oxazolines is described.
A convenient and highly regio‐specific deuteriation of the pterocarpanoid phytoalexin maackiain
Authors: Stoessl Albert , Stothers J. B. 
Published: October 2006

AbstractA procedure is described which allows specific deuteriation at the 4‐position of maackiain (3‐hydroxy‐8,9‐methylenedioxypterocarpan) to the extent of about 30%.
Synthesis of 14C‐ and 3H‐labelled β ‐casomorphin‐5
Authors: Hartrodt B. , Toth G. , Neubert K. , Sirokmán F. , Baláspiri L. , Schulz H. 
Published: October 2006

Abstractβ‐casomorphin‐5, tyrosyl‐prolyl‐phenylalanyl‐prolyl‐glicine, labelled with 14C and 3H in the N‐terminal tyrosine residue, was synthesized by stepwise elongation, using [Dit]1‐β‐casomorphin‐5 as precursor for catalytic tritiation. The specific radioactivities of the two peptides were 1.6 mCi/mmol [59.2 MBq/mmol] and 44.1 Ci/mmol [1.63 /Bq/mmol], respectively. Both were biologically fully active as compared with a synthetic reference material.
A facile synthesis of [1‐13C]benzonitrile by bromination‐dehydrobromination of [1‐13C]1‐cyanocyclohexene
Authors: Yuan Sun‐Shine , Ajami Alfred M. 
Published: October 2006

Abstract[1‐13C]1‐Cyanocyclohexene can be bisbrominated by N‐bromosuccinimide and then aromatized by triethylamine to give [1‐13C] benzonitrile in 90% yield. This allylic bisbromination‐dehydrobromination reaction is generally applicable to the transformation of other 1‐substituted cyclohexenes into benzenoid derivatives.
Synthesis of 14C‐labelled bis‐azo biphenyl dyes
Authors: Milam D. Franklin , Lynn Robert K. 
Published: October 2006

AbstractTwo 14C‐labelled bis‐azo biphenyl dyes have been prepared from uniformly ring‐labelled 14C‐benzidine and 14C‐3, 3′‐dimethylbenzidine. The amines were tetra‐azotized with sodium nitrite and HCL. Direct Blue 6 was then prepared from tetra‐azo benzidine by allowing it to react with two equivalents of H acid (8‐amino‐1‐naphthol‐3,6‐disulfonic acid mono sodium salt) under basic conditions. Acid Red 114 was prepared from tetra‐azo 3,3′‐dimethylbenzidine by sequential reaction with one equivalent of G acid (2‐naphthol‐6,8‐disulfonic acid dipotassium salt) followed by one equivalent of phenol. This product was then esterified with p‐toluenesulfonyl chloride to give acid Red 114.
Synthesis of p125I ‐amphetamine
Authors: Duterte D. , Morier E. , le Poncin‐Lafitte M. , Rapin J. R. , Rips R. 
Published: October 2006

Abstractp‐iodo‐amphetamine was synthesized by the Sandmeyer reaction from iodine and p‐NH2‐amphetamine, in which the amino aliphatic group was protected by an easily hydrolysable group: t‐butyloxycarbonyl. Iodine was obtained by oxidation of Na 125I with periodate in an acidic medium. The yield was 50% with a specific activity of 25 mCi/mmol.
Solution synthesis of 14C‐labeled thymopoietin32–36 using catalytic transfer hydrogenation as the final deprotection step
Authors: Tjoeng Foe‐Siong , Heavner George A. 
Published: October 2006

AbstractA 14C‐labeled pentapeptide, [14C]Arg‐Lys‐Asp‐Val‐Tyr (6), corresponding to the active fragment 32–36 of thymopoietin II has been synthesized by a solution method with a 44 percent radiochemical yield. 14C‐labeled Z‐Arg(HCl)‐OH was coupled to the protected tetrapeptide Lys(Z)‐Asp(OBzl)‐Val‐Tyr(Bzl)‐OBzl using dicyclohexylcarbodiimide and 1‐hydroxybenzotriazole to give the protected pentapeptide 5 with a specific activity of 340 mCi/mmol. Catalytic transfer hydrogenation was used to remove the protecting groups and the free peptide was purified by gel filtration and high performance liquid chromatography.
A novel method for the preparation of adenosine 3′5′ cyclic phosphate labelled with 14C or 3H
Authors: Pandey V. N. , Nair C. K. K. , Pradhan D. S. 
Published: October 2006

AbstractHigh yields of cyclic AMP (cAMP) and cyclic GMP (cGMP) could be obtained by near quantitative conversions of adenine and guanine by aerobically‐grown nonproliferating cells of Corynebacterium murisepticum. The procedure is especially suited for the preparation of 14C or 3H labelled cAMP and cGMP from respective purine base precursors.
Syntheses Nouvelles DE LA Mevalonolactone Marquee Au 14C, 13C, 3H ‐ (RS) Mevalonolactone (14C‐3′) et (RS) Mevalonolactone (3H‐3′)
Authors: Rousseau Bernard , Beaucourt Jean‐Pierre , Pichat Louis 
Published: October 2006

AbstractTwo procedures are described for the two step synthesis of [3′‐14C] mevalonolactone and [3H‐methyl] mevalonolactone from radioactive methyl magnesium iodide. The first route involves the addition of radiolabeled methyl magnesium iodide with 1(2,4,10 trioxa adamantyl) 4‐trityloxy 2‐butanone : 6 followed by hydrolysis with acid. The overall yield from methyl iodide was 37 % : specific activity 49 mCi/mMol. [3‐13H] mevalonic acid was prepared by the same technique at a specific activity of : 3,8 Ci/mMol. The second route relies on the addition of radiolabeled methylmagnesium iodide upon 1,1‐dimethoxy 5‐(2‐tetrahydropyranyloxy)‐3‐pentanone : 12 followed by the oxidative hydrolysis of the reaction product with bromine‐water‐hydrochloric acid. The overall yield was 40 % from methyl iodide : specific activity : 1 mCi/mMol. The multi step synthesis of synthons : 6 and 12 are fully described.
Syntheses of chirally labelled [4‐13C]‐β‐hydroxyvaline and [4,4,4‐2H3]‐β‐hydroxyvaline
Authors: Aberhart D. John 
Published: October 2006

Abstract(E)‐[4‐13C]‐3‐Methylcrotonic acid was converted to [4‐13C]‐3‐methyl‐2,3‐epoxybutyric acid, which was treated with ammonia to yield a mixture of [4‐13C]‐β‐hydroxyvaline and [4‐13C]‐β‐amino‐α‐hydroxyisovaleric acid, from which the β‐hydroxyvaline of known chirality at C‐3 relative to C‐2 was isolated. Similarly, (E)‐[4,4,4‐2H3]‐3‐methylcrotonic acid was converted via the epoxide, into a mixture of [4,4,4‐2H3]‐β‐hydroxyvaline and [4,4,42H3]‐β‐amino‐α‐hydroxyisovaleric acid, from which the β‐hydroxyvaline was isolated.
Reaction of 14CO2 with grignard reagents to form either carboxylic acids or ketones. A novel convenient route to [2‐14C] glycerol and [1‐14C] Glycolic acid
Authors: Wirz B. , Küng W. 
Published: October 2006

AbstractThe reaction of CO2 with GRIGNARD reagents carrying an ether grouping in a sterically suitable position can be directed to afford predominantly either the carboxylic acid or the symmetrical ketone. Thus, the magnesiumorganic compounds prepared from chloromethyl‐methyl ether, benzyl‐chloromethyl ether and 2‐methoxy‐bromobenzene, upon treatment with CO2 under appropriate conditions give the corresponding ketones in excellent yield. An attempt is made to rationalize this finding from a mechanistic viewpoint. The easily accessible 1,3‐bis(benzyloxy)‐acetone represents a convenient intermediate for an efficient and simple synthesis of glycerol.
Synthese DE LA pentamethylmelamine (tetraméthyle 14C), un nouvel agent antitumoral
Authors: Do‐Cao‐Thang  , Nguyen‐Hoang‐Nam  , Hoellinger H. , Pichat L. 
Published: October 2006

Abstract(tetramethyl‐ 14C)Pentamethylmelamine 6, a new antitumor agent, was prepared by a three‐step synthesis starting with (14C)CH3I. Toluene‐p‐sulphonamide was condensed with (14C)CH3I to give labelled NN‐dimethyltoluene‐p‐sulphonamide. 14C‐labelled dimethylamine was released from the dimethylamide by the action of 48% HBr and NaOH, then reacted with 2,4‐dichloro‐6‐methylamino‐1,3,5‐triazine to afford 6. After purification by silicagel column chromatography 6 was obtained in a 8.5% yield from (14C)CH3I and a radiochemical purity of 99%, specific activity : 78.5 mCi/mmole.
Radiosynthesis of high specific activity tritium‐labeled precocene II
Authors: Bowers William S. , Franke Lothar , Soderlund David M. 
Published: October 2006

AbstractThe insect antijuvenile hormone precocene II (6,7‐dimethoxy‐2,2‐dimethylchromene) was radiosynthesized, incorporating tritium specifically in the gem‐dimethyl group at high specific activity. 7‐Hydroxycoumarin was methylated (CH3I/KOH) and then oxidized at 6‐position (K2S2O8/NaOH). The resulting 6‐hydroxy‐7‐methoxycoumarin was methylated (CH3I/KOH) and reacted with excess C3H3MgI to give precocene II‐[2‐methyl‐3H] at a specific activity of 32 Ci/mmol. This synthetic scheme offers access to radiolabeled preparations of a wide variety of mono‐ and dialkoxy‐substituted analogues of precocene II.
The synthesis of [4,6‐2H] salicylates
Authors: Hall C. Richard , Ley Ronald V. 
Published: October 2006

Abstract[4,6‐2H] Salicylic acid, salicyluric acid and methyl salicylate are prepared by hydrogenolysis of 3,5‐dichlorophenol followed by carboxylation with sodium ethyl carbonate.
Synthesis of 2,4′,5‐trichloro [14C]biphenyl mercapturic acids
Authors: Bergman Ake , Bakke Jerome E. , Feil Vernon J. 
Published: October 2006

AbstractThe synthesis of 3‐ and 4‐S‐(N‐acetyl)cysteinyl‐2,4′,5‐trichloro[14C]biphenyl is described. 4‐Chloro[14C]aniline was used as starting material. The products were obtained after an aryl coupling of the amine with 2,5‐dichloronitrobenzene, a reduction of the nitrogroup and finally coupling of the diazotized trichlorobiphenyl amine with cuprous N‐acetylcysteine mercaptide.
Synthesis of model oligosaccharides of biological significance. 3. Synthesis of carbon‐13 labelled trimannosides
Authors: Winnik F. M. , Carver J. P. , Krepinsky J. J. 
Published: October 2006

AbstractTwo isomeric trimannosides labelled with carbon‐13 at one specific anomeric position have been synthesized. Methyl 2‐O‐allyl‐4,6‐O‐benzylidene‐α‐D‐mannopyranoside was reacted with tetra‐O‐acetyl‐D‐mannopyranosyl‐1‐13C bromide. The disaccharide obtained was glycosylated with tetra‐O‐acetyl‐D‐mannopyranosyl bromide after hydrolysis of the benzylidene group. This sequence led to methyl 3‐O‐α‐D‐mannopyranosyl‐α‐D‐mannopyranoside after deblocking of all hydroxyl groups. When the 13C‐labelled and unlabelled glycosyl bromides were added to the methyl mannoside in the reversed order, methyl 3‐O‐α‐D‐mannopyranosyl‐6‐O‐α‐D‐mannopyranosyl‐1‐13C‐α.D‐mannopyranoside was obtained.
Synthesis of 35S‐ and 14C‐labeled famotidine, a new potent histamine H2 receptor antagonist
Authors: Tamazawa Kazuharu , Arima Hideki 
Published: October 2006

AbstractFamotidine, 3‐[[[2‐[(diaminomethylene)amino]‐4‐thiazolyl]methyl]thio]‐ N2‐sulfamoylpropionamidine, a new potent histamine H2 receptor antagonist, was labeled with 35S and 14C for metabolic studies at specific activities of 45.7 μCi/mg (VIb) and 47.6 μCi/mg (VIc) respectively.
Triethyl [1‐14C]phosphonoacetate from [14C]carbon dioxide
Authors: Crevoisier Michel , Guilford William J. , Coates Robert M. 
Published: October 2006

AbstractLithiation of diethyl methylphosphonate (1) with n‐butyllithium followed by carbonation with [14C]carbon dioxide and esterification with diazoethane afforded high specific activity triethyl [1‐14C]phosphonoacetate (4) in 62% yield.
Preparation of [5‐125I]iodoacetamidoethyl aminonaphthalene‐1‐sulfonic acid in liposomes
Authors: Ogawa Naotaka , Jay Michael 
Published: October 2006

AbstractThe synthesis of [5‐125I]iodoacetamidoethyl aminonaphthalene‐1‐sulfonic acid ([125]IAEDANS) was accomplished beginning from sodium [125I]iodide. The product was entrapped within positively charged liposomes after ideal preparatory conditions were determined. The stability of the preparation after exposure to elevated temperatures and light was measured as well as the release rate of [125I]IAEDANS from the liposomes. Liposome‐entrapped [125I]IAEDANS is a potential radiopharmaceutical for imaging of infarcted myocardial tissue.
Radioactively labelled epoxides. Part IV. Tritium labelled α‐ and β‐methyl styrene oxides
Authors: Oesch Franz , Sparrow Alan J. , Platt Karl L. 
Published: October 2006

AbstractTritium labelled α‐methyl styrene oxide (2‐methyl‐2‐phenyloxirane) and cis‐ and trans‐β‐methyl styrene oxides (Z‐ and E‐2‐methyl‐3‐phenyl oxirane) have been prepared using tritiated water as the inexpensive source of tritium. The two geometrical isomers of β‐methyl styrene oxide were synthesized by a sequence of reactions which led to stereochemically pure products, and obviated any need to separate the isomers.
Determination of specific activity of radiohalide preparations (75Br, 77Br, 123I, 131I) by HPLC‐UV detection following chemical derivatization to 1‐halonaphthol‐2
Authors: Kloster Gerd , Laufer Peter 
Published: October 2006

AbstractSpecific activity is an important parameter for receptor‐binding radiopharmaceuticals. We present here a method for determination of specific activities of radiobromide (75Br, 77Br) and radioiodide (123I, 131I) using naphthol‐2 and chloramin T as reagents for derivatization. Subsequent hplc determination of the mass of 1‐halo‐naphthols‐2 on a RP 18 column is highly sensitive due to their high UV extinction coefficient in the range of 232 nm (detection limit at 220 nm: 5 × 10−13 mol) and linear over 6 orders of magnitude. It can be rapidly and conveniently performed in parallel to the actual radiopharmaceutical preparation using only a small part of the radioactive halide (less than 1 mCi for all isotopes). Dilution factors (carrier atoms per radioactive atom) found for the radiohalide using this method were 21‐100 for 75Br, 2–58 for 77Br, 3–6 for 123I and 120‐130 for 131I, respectively.
Tritium and iodine labelling of a gastrin like hexapeptide
Authors: Charon Marie‐Hélène , Van Chuong Paul Pham , Penke Botond , Morgat Jean‐Louis , Dubrasquet Marcelle , Fromageot Pierre 
Published: October 2006

AbstractTyrosine derivatives were introduced onto the N‐terminal deprotected Pentagastrin to yield precursors of labelling. The tritiated derivative Boc‐3,5‐3H2‐Tyr‐Pentagastrin of high specific radioactivity (45 Ci/mmol) was obtained by catalytic dehalogenation of the corresponding di‐iodo‐derivative in the presence of tritium gas. Iodination of Boc‐Tyr‐Pentagastrin by NaI and chloramine T led to the formation of several compounds separated by HPLC. Conditions to obtain the mono‐iodinated non‐oxidized peptide, the only biologically active derivative, were investigated. Analytical chromatographic behaviour as well as biological activity of the tritiated and of the various iodinated peptides were reported.
Synthesis of 14C labelled heptacaine and carbisocaine, new local anaesthetics
Authors: Elbert Tomáš , Marko Vladimír , Filip Jiří , Beneš Luděk 
Published: October 2006

AbstractThe published four step synthesis of N‐{2‐(2‐heptyloxyphenyl‐carbamoyloxy)‐ethyl}‐piperidinium chloride (5) and N‐{2‐(2‐heptyl‐oxyphenylcarbamoyloxy)‐propyl}‐diethylammonium chloride (6), which starts from o‐acetamidophenol and 1‐bromoheptane was scaled down and modified for radioisotope work. After chromatography 1064 MBq (28,7 mCi) of [heptyl‐1‐14C]heptacaine 5 and 840 MBq (22, 6 mCi) of [heptyl‐1‐14C]carbisocaine 6 were isolated. Radiochemical yields of 5 and 6 on starting 1‐bromo [1‐14C] heptane were 30% and 25%, respectively.
A simple, rapid synthesis of caffeine‐1,7‐13CH3
Authors: Pierce W. M. , Schlager J. J. , Madden R. J. , Hurst H. E. 
Published: October 2006

AbstractThis paper describes a simple, rapid synthesis of caffeine‐1,7‐13CH3 produced by the reaction of iodomethane‐13C with 3‐methylxanthine. The synthesis is complete in one day, requires only the most rudimentary laboratory equipment, and is amenable to large scale synthesis. Overall yield after product isolation is 82%, and the product is of 99% chemical purity and 99% isotopic purity.
Synthesis of 3‐amino‐1‐methyl‐5H‐pyrido[4,3‐b]indole‐1‐14C (TRP‐P‐2)
Authors: Reist E. J. , Bradford W. W. , Gordon G. R. , Peters J. H. 
Published: October 2006

AbstractA practical 2‐step synthesis of 3‐amino‐1‐methyl‐5H‐pyrido[4,3‐b]indole‐1‐14C is described, starting from 2‐cyanomethyl indole and carbonyl‐labeled acetyl chloride.
Synthesis of [14C]‐labelled tolrestat(N‐[[5‐(trifluoromethyl)‐6‐methoxy‐1‐naphthalenyl]‐[14C]thioxomethyl]‐N‐methylglycine; AY‐27, 773)
Authors: Hicks D. R. 
Published: October 2006

Abstract[14C]‐Tolrestat(N‐[[5‐(trifluoromethyl)‐6‐methoxy‐1‐naphthalenyl]‐[14C]‐thioxomethyl]‐N‐methylglycine; [14C]AY‐27, 773), a new aldose reductase inhibitor, was prepared by incorporating [14C]carbon dioxide. The intermediate, 6‐methoxy‐5‐trifluoromethyl‐[1–14C]‐naphthoic acid, prepared by carbonation of the corresponding lithiated derivative, was condensed with sarcosine methyl ester hydrochloride, converted to the thioamide and hydrolyzed. [14C]Tolrestat, having a specific activity of 52.7 μCi/mg was obtained in 26% overall yield from [14C]barium carbonate and had a radiochemical purity of 97%.
Synthesis of site specifically deuterated primaquines II. N‐alkyl deuterated primaquines
Authors: McChesney James D. , Sarangan Srinivasan 
Published: October 2006

AbstractTwo site specifically deuterated primaquines were prepared. 4′,4′‐Dideutero primaquine 3 was obtained from the corresponding dideutero alcohol which was prepared by the low temperature reduction of the ester compound 4 with lithium aluminium deuteride. 1′‐Deutero primaquine r was prepared by the reductive alkylation of 6‐methoxy‐8‐aminoquinoline with N‐(2‐oxopentyl)‐phthalimide in the presence of sodium cyanoborodeuteride followed by removal of protective phthalimide group.
Synthesis of 13C labeled n‐alkylchlorosi lanes
Authors: Gilpin R. K. , Gangoda M. E. 
Published: October 2006

AbstractThis report describes the synthesis of various carbon‐13 enriched n‐alkylchlorosilanes with label in corporation at selective positions along the alkyl chains. Compounds which were prepared were:

n‐nonyltrichlorosilane‐1‐13C
n‐dodecyltrichlorosilane‐4‐13C
n‐dodecyldimethylchlorosilane‐4‐13C
n‐tridecyltrichlorosilane‐12‐13
n‐dodecyltrichlorosilane‐12‐13C
n‐tridecyldimethylchlorosilane‐12‐13C
Synthesis of sodium [1,4‐14C] aurothiomalate
Authors: Taylor Andrew , King Laurence J. , Marks Vincent 
Published: October 2006

Abstract[1,4‐14C] Acetylthiomalic anhydride was prepared from [1,4‐14C]maleic anhydride and thioacetic acid. Removal of the acetyl group was achieved by sodium hydroxide hydrolysis and the resultant [1,4‐14C]thiomalic acid was extracted into ethyl acetate. Sodium [1,4‐14C]aurothiomalate was prepared by the reaction of gold(I) iodide with [1,4‐14C] thiomalic acid and precipitation of the sodium salt from alkaline solution by the addition of ethanol. The products were demonstrated to have a radiochemical purity of > 98% by radio‐scanning of thin‐layer chromatograms and scintillation counting of segments of the chromatogram.
Synthesis of 14C‐labeled pramiracetam hydrochloride, N‐[2‐(bis[1‐methylethyl]amino)ethyl]‐2‐oxo‐1‐pyrrolidine‐acetamide‐α‐14C hydrochloride, CI‐879 hydrochloride
Authors: Hartman Jon D. , Huang C. C. , Butler D. E. 
Published: October 2006

AbstractPramiracetam hydrochloride, N‐[2‐[bis(1‐methylethyl)amino] ethyl]‐2‐oxo‐1‐pyrrolidineacetamide hydrochloride, CI‐879, a new potential clinically useful cognition activator, was labeled with 14C. Bromoacetic‐2‐14C acid was converted to its ethyl ester which reacted with sodium 2‐pyrrolidinone to yield ethyl 2‐oxo‐1‐pyrrolidineacetate‐α‐14C acid. Treatment of the latter with N,N‐bis(1‐methylethyl)‐1,2‐ethanediamine gave pramiracetam free base which was subsequently converted to the hydrochloride salt.
Synthesis of 2H, 13C and 15N‐isotopomers of acetonitrile and thioacetamide
Authors: Anthoni Uffer , Nielsen Per Halfdan 
Published: October 2006

AbstractThe syntheses of all the possible 2H, 13C, and 15N singly and multiply labelled isotopomers of acetonitrile and thioacetamide are described. The pathway includes reaction between methyl iodide and potassium cyanide followed by treatment of the acetonitrile with diphenylphosphinodithioic acid to give thioacetamide, purified by sublimation in an overall yield of 55–60%.
Synthesis of (2RS)‐[3‐13C]‐ and (2RS)‐[3‐14C] leucine
Authors: Anastasis Panayiotis , Overton Karl , Singh Sheo Bux 
Published: October 2006

Abstract(2RS)‐[3‐13C]‐ and (2RS)‐[3‐14C] Leucine have been prepared via carbonation of the Grignard reagent 2 from 2‐bromopropane, with 13CO2 or 14CO2. Reduction of the labelled isobutyric acid, displacement of the derived isobutyl brosylate 5 with acetamidomalonic ester and hydrolysis afforded (2RS)–[3‐*C] leucine with 55–65% incorporation of label from Ba*CO3 on a scale of 5–25 mmol.