bluuebunny/crossref_metadata_2025_split huggingface dataset:
Routine production of 2‐deoxy‐D‐[1‐11C]glucose : An alternative
Authors: van Haver D. , Rabi N. A. , Vandewalle M. , Goethals P. , Vandecasteele C. 
Published: October 2006

AbstractThe routine production of 2‐deoxy‐D‐[1‐11C]glucose (11C‐glucose (11C‐2DG) from [11C]hydrogen cyanide and 2,3:4,5‐di‐O‐isopropylidene‐1‐iodo‐D‐arabinitol is described. The nitrile intermediate is purified by high‐performance liquid chromatography (HPLC) before reduction/hydrolysis with Raney alloy in formic acid. The radiopharmaceutical is isolated by ion exchange and is obtained in a radiochemical yield of 20 % with a synthesis time of 50–55 min. A typical run affords 25–30 mCi of 11C‐2DG with a specific activity of 90–100 mCi/mg.
Synthesis of (2R)‐ and (2S)‐[3‐2H]‐valine
Authors: Easton Christopher J. , Findlay Nicola G. 
Published: October 2006

Abstract(2R)‐Valine and the (2S)‐isomer were esterified and bezoylated. The derivatives were chlorinated at C‐3 by treatment with sulphuryl chloride, reduced to the 3‐2H derivatives by reaction with triphenyltin deuteride, then hydrolysed to give (2R)‐ and (2S)‐[3‐2H]‐valine. The labelling is achieved with complete retention of optical purity.
Aromatic fluorination with N.C.A. F‐18 fluoride: A comparative study
Authors: Berridge M. S. , Crouzel C. , Comar D. 
Published: October 2006

AbstractFluorination of aromatic rings with no carrier added (n.c.a.) 18F‐fluoride was investigated using aryl triazenes and aryl iodides as substrates. Aryl triazenes give low yields of labeled under all conditions, and evidence was obtained to indicate that an inert solvent was unnecessary for the reaction. Nucleophilic substitution of aromatic iodides in DMSO was found to be a superior method of fluorination yielding up to 70% incorporation of label. The scope and limitations of this new labeling reaction are reported.
Synthesis of tritium‐labelled iohexol
Authors: Herscheid J. D. A. , Jacobsen T. , Skinnemoen K. , Valk J. , Hoekstra A. 
Published: October 2006

AbstractIn an efficient three‐step synthesis [3H] glycerol was converted into α‐tosyl‐ [3H] glycerol (yield: 77%), from which [3H] iohexol was prepared in an overall radiochemical yield of 25% and a specific activity of 400 m̈Ci/mmol. Performing the synthesis on a microscale, the overall yield decreased to only 4%, but a 99% pure [3H] iohexol with a specific activity of 1 Ci/mmol was obtained.
Synthese de la Letosteine: Marquee AU 14C ET AU 35S
Authors: Nicolas Colette , Gachon Francloise , Faurie Michel 
Published: October 2006

AbstractLETOSTEINE, 2‐[1ethoxy carbonyl methylthio)‐ethyl] 4‐hydroxycarbonyl thiazolidine is labelled with either carbon‐14 or Sulfur‐35 on the following positions:
‐ the carboxylic carbon of the ester function by means of chloro (1‐14C)‐acetic acid.
‐ the thiazolidinyl group by means of L‐(35S)‐cysteine.
Specific activities are 0,373 mCi/mMole or 13,8 MBq/mMole for 14C‐LETOSTEINE and 9,90 mCi/mMole or 366 MBq/mMole for 35S‐LETOSTEINE.
Synthesis of carbon‐14 and deuterium labeled 3‐isobutyryl‐2‐isopro‐pylpyrazolo [1, 5‐a]pyridine
Authors: Nagatsu Yoshio , Takagi Koichi 
Published: October 2006

AbstractIn order to study the metabolic fate of 3‐isobutyryl‐2‐isopropylpyrazolo [1, 5‐a]pyridine (I, KC‐404: antiasthmatic agent) in experimental animals and humans, the synthesis of I labeled with carbon‐14 or deuterium was investigated. Carbon‐14 labeled I was obtained from 5 mCi of isobutyric acid‐1‐14C sodium salt with a 67.7% yield. Its specific activity was 24.7 m̈Ci/mg. Deuterium labeled I was synthesized from pyridine‐d5 with a 17.8% yield, which resulted in about 50% replacement of deuterium with hydrogen at the position 7 in I. The release of deuterium apparently did not occur on GC‐MS. The mixture of deuterium labeled I and unlabeled I (2:1 mole ratio) supplied nearly the same intensity of triplet ions (ion clusters) used for identification of I and its metabolites.
Synthesis of 14C‐labelled 2‐[2‐cyclohexylcarbonyloxy‐3‐{4‐(2‐pyridyl) piperazin‐1‐yl}propyl]‐3aα, 4β, 7β, 7aα‐tetrahydro‐4, 7‐methano‐isoindole‐1,3(2H)‐dione dihydrochloride (E‐0713)
Authors: Miyake Kazutoshi , Chiku Shigeru , Sohda Shigeru 
Published: October 2006

AbstractA 14C‐labelled form of the antidiabetic compound E‐0713 was synthesized for pharmacokinetic and metabolic studies in six steps, using maleic anhydride [2,3‐14C] as the labelled starting meterial.
Synthesis of C‐13 labeled vitamin E, [4′a‐13C]all‐rac‐α‐tocopherol1)
Authors: Urano Shiro , Muto Riko , Matsuo Mitsuyoshi 
Published: October 2006

AbstractVitamin E with a 13C‐labeled isoprenoid side chain, [4′a‐13C]‐all‐rac‐α‐tocopherol (1), was synthesized by the coupling reaction of 6‐methoxymethoxy‐2‐([4‐methyl‐13C]5‐bromo‐4‐methyl‐pent‐l‐yl)chroman (8) with 3,7‐dimethyl‐1‐(thiazolin‐2‐yl) thio‐2,6‐octadiene (9). Compound 8 was prepared using 2‐(4,4‐diethoxycarbonylbut‐1‐yl)‐6‐methoxymethoxy‐2,5,7,8‐tetramethyl‐chroman (5) as a key intermediate and [13C]methyl iodide as a 13C source. The total yield of the labeled α‐tocopherol based on [13C]methyl iodide was 58.7%.
Synthesis of 2‐n butyl 3‐(3,5‐125diiodo 4‐(N, N‐diethylamino 2‐ethoxybenzoyl)) benzofuran hydrochloride (125I amiodarone)
Authors: Sion R. 
Published: October 2006

Abstract125I Amiodarone was prepared by iodination of 2‐n butyl 4‐hydroxy 3‐benzoyl benzofuran with Na125I in alkaline medium. By amination with N, N‐diethyl 2‐amino 1‐chloroethane, 125I amiodarone was obtained with 30 % yield and a specific activity of about 1 Ci/mmol.
Synthesis of |24‐14C|‐3β,14β,20ε‐trihydroxy‐23‐nor‐5β‐cholanoic acid
Authors: Maier M. S. , Seldes A. M. , Gros E. G. 
Published: October 2006

AbstractThe synthesis of |24‐14C|‐3β,14β,20ε‐trihydroxy‐23‐nor‐5β‐cholanoic acid was accomplished by Reformatsky reaction of ethyl |1‐14C|‐bromo acetate with 3β‐acetoxy‐14β‐hydroxy‐5β‐pregnan‐20‐one which was obtained from digitoxigenin. The final and intermediate products were characterized by spectroscopic (IR, 1H and 13C‐NMR, MS) methods.
Synthesis of 1‐13C‐1‐indanone and 2‐13C‐1,2,3,4‐tetrahydroquinoline
Authors: Pickering R. E. , Wysocki M. A. , Eisenbraun E. J. 
Published: October 2006

AbstractThe synthesis of 2‐13C‐1,2,3,4‐tetrahydroquinoline (5) via 1‐13C‐3‐phenylpropanoic acid (1), 1‐13C‐1‐indanone (2), 1‐13C‐1‐indanone hydrazone (3) and 2‐13C‐3,4‐dihydro‐2(1H)‐quinolinone (4) proceeded in 78, 96, 95, 79, and 85% individual yields respectively for 1, 2, 3, 4, 5 and 61% overall yield of the latter from 1.
Synthesis of 14‐methyl[2,3‐3H]hexadecanoic acid
Authors: Helmich O. , Streibl M. , Filip J. , Hradec J. 
Published: October 2006

Abstract14‐Methyl[2,3‐3H]hexadecanoic acid of a specific radioactivity of 51 Ci/mmol was prepared starting from 12‐methyl‐tetradecanoic acid isolated from wool fat. This fatty acid was converted into 12‐methyltetradecanal which was reacted with ethyl diethylphosphonoacetate to yield 14‐methylhexadecen‐2‐oic acid. The resulting compound was tritiated with gaseous 3H2 in the presence of a 5% Pd/BaSO4 catalyst. The reaction in dried dioxane gave products of a specific radioactivity corresponding to 87.9% of the theoretical value.
Synthesis of 1‐(2‐deoxy‐2‐fluoro‐β‐D‐arabinofuranosyl)‐5‐iodo [2‐14C] uracil
Authors: Swigor J. E. , Pittman K. A. 
Published: October 2006

AbstractThe synthesis of the title compound (7) is described. [2‐14C] cytosine (1) is treated with an aqueous mixture of sodium bisulfite and sodium sulfate at 80°C for 30 min. The resulting solid is then treated with aqueous sodium hydroxide and passed through a cation exchange column, producing [2‐14C] uracil (2). Iodionation with iodic acid and iodine in acetic acid yielded 5‐iodo‐[2‐14C]uracil (3) Treatment of (3) with hexamethyldisilazane formed the trimethylsilated pyrimidine. Condensation with 3‐0‐acetyl‐5‐0‐benzoyl‐2‐deoxy‐2‐fluoro‐D‐arabinosyl bromide produced a mixture of α, β isomes. Separation by column chromatography and saponification with aqueous potassium carbonate yielded the title compound.
Assessment of 99mTc‐labelled gentamicin in renal functional imaging
Authors: Özker Kutlan , Urgancioǧlu Irfan 
Published: October 2006

AbstractAn aminoglycoside antibiotic, gentamicin is labelled with 99m Tc by the stannous chloride reduction. Scintigraphic studies and organ distribution of this agent in experimental animals showed a selective renal localization. The radioactivity remained for a relatively long period in the kidneys suggesting some tubular reabsorption following filtration at the glomerular level. The concentration of 99m Tc‐gentamicin in the kidneys as a function of time has been studied by a gamma camera interfaced to a computer. Renal radioactivity clearance curves were generated from the regions of interests on each kidney. The potential value of 99m Tc‐gentamicin in the diagnosis of functional disorders with relation to the glomerular filtration and reabsorption in the proximal nephron is discussed.
Synthesis of carbon‐14 labeled cilobamine mesylate
Authors: Wagner E. R. , Hamilton C. T. 
Published: October 2006

AbstractCilobamine mesylate, cis‐2‐(3,4‐dichlorophenyl‐UL14C)‐3‐[(1‐methylethyl)‐amino]bicyclo[2.2.2]octan‐2‐01 methanesulfonate 1, a new antidepressant, was synthesized in 15% yield from the Grignard reaction of 1‐bromo‐3,4‐dichloro‐benzene‐UL14C and 3‐[(1‐methylethyl)amino]bicyclo[2.2.2]octan‐2‐one, 5. The bicycloketoamine 5 was prepared in three steps from bicyclo[2.2.2]oct‐2‐ene.
Synthesis of no‐carrier‐added radiobrominated N‐alkylated analogues of spiperone
Authors: Moerlein S. M. , Laufer P. , Stöcklin G. 
Published: October 2006

AbstractThe synthesis of a series of p‐bromo‐3‐N‐alkyl spiperone analogues is described. N‐alkylation was achieved via reaction of the potassium salt of the spiperone lactam ring with alkyl iodide; subsequent reactions with elemental bromine gave the p‐brominated isomers. Optimization studies using no‐carrier‐added (n.c.a.) 77Br− indicated that radiobromination of N‐alkyl spiperone analogues occurs with higher yields and in shorter reaction times when dichloramine‐T (DCT) is used rather than H2O2/acetic acid as an oxidant. The production of the title compounds in high effective specific activity with radiochemical yields of 20–30 % using n.c.a. 77Br− and DCT is reported.
Preparation of tritium labelled benzamide dopamine‐D2 lignads at high specific activity
Authors: Gawell Lars , Hall Häkan , Köhler Christer 
Published: October 2006

AbstractA method for the preparation of tritium labelled potential neuroleptics of the benzamide class possessing highly potent dopamine‐ D2 binding properties, is described. The pyrrolidine moiety of the molecule is labelled with tritium by hydrogenation, to a specific activity of up to 58 Ci/mmol and subsequently reacted with an acid chloride. The specificity of the label is confirmed by 3H‐NMR.
Synthesis of 14C‐labelled dibenzo[d, g] [1,3,6]dioxazocine derivatives (EGYT‐2474 and EGYT‐2509)
Authors: Birkás‐Faigl E. , Engler J. , Zólyomi G. , Rózsa L. 
Published: October 2006

AbstractSynthesis of 2‐chloro‐12‐(3‐dimethylaminopropyl)‐dibenzo[d, g] [1,3,6]dioxazocine maleate (EGYT‐2474) and 2‐chloro‐12‐(3‐dimethylamino‐2‐methylpropyl)‐di‐benzo[d, g] [1,3,6] dioxazocine hydrochloride (EGYT‐2509) labelled with 14C‐isotope is reported. The synthesis of above compounds was based on [14C] methylene diiodide which was prepared by the reduction of [14C]iodoform. [14C]Iodoform was synthesised by an improved method in a radiochemical overall yield of 44% calculated on barium [14C]carbonate.
Synthesis of 2‐[2‐14C]‐(2‐aminoethyl)‐thiazole dihydrochloride: Thiazolyl ethylamine dihydrochloride
Authors: Armitage M A , Saunders D 
Published: October 2006

AbstractThe histamine H1 agonist, 2‐[2‐14C]‐(2‐aminoethyl)‐thiazole dihydrochloride has been labelled with carbon‐14 in the 2 position of the thiazole starting from potassium [14C] cyanide. The overall radiochemical yield for the synthesis was 17% at a specific activity of 36mCi/mmol.
Synthesis of 11C‐suriclone
Authors: Boullais C. , Oberdorfer F. , Sastre J. , Prenant C. , Crouzel C. 
Published: October 2006

Abstract11C‐Suriclone was synthetised in a short time (30 minutes) with a high specific activity (750 mCi/ m̈Mol) for studies in man with the Positron Emission Tomography technic. The starting material was the N‐demethylated product 35489 RP. The radioactive reagent was either 11C‐formaldehyde or 11C‐methyl iodide.
A convenient regio‐ and stereospecific synthesis of 2H‐labelled methyl trans‐chrysanthemate
Authors: Saljoughian Manoucher 
Published: October 2006

AbstractThe methyl ester of trans‐chrysathemic acid (a constituent of natural pyrethrins) has been regio‐ and stereospecifically deuteriated in the olefinic (76%D) and the cyclopropane ring (67%D) protons in a one stage synthesis as shown by 1H nmr spectroscopy.
Radioiodinations of organic molecules on silica gel surfaces
Authors: Boothe Thomas E. , Finn Ronald D. , Vora Manhar M. , Emran Ali , Kothari Paresh J. , Kabalka George W. 
Published: October 2006

AbstractTo investigate radioiodinations on chromatographic surfaces, 131I− has been allowed to react with various organic compounds on silica gel chromatography plates. Antipyrine, which reacts with 131I− to give 4‐[131I]iodoantipyrine, was used as a model compound. The yield varied as a function of the initial solvent used; hydrogen ion concentration; contact time on the surface; and temperature. These results were extended to other reactive compounds such as substituted 3H‐pyrazol‐3‐ones; substituted phenols, including L‐tyrosine; substituted anilines; 5‐iodouracil; some secondary alkyliodides and alkylbromides; alkylboranes; and aryl‐and vinylboronic acids.
Synthesis of oxygen‐17 labeled thyrotropin releasing hormone
Authors: Ponnusamy E. , Fiat D. 
Published: October 2006

AbstractOxygen‐17 isotope was introduced into the α‐carboxyl group of L‐proline and L‐pyroglutamic acid by acid catalysed exchange of oxygen‐17 from H2 17O or acid hydrolysis of respective amino acid methyl esters in presence of HCl/H2 17O. The α‐amino group of the amino acids were protected by tertbutyloxycarbonylation. Two analogues of thyrotrop in releasing hormone, one enriched with [17O] at the proline carboxamide oxygen (I) and the other at the pyroglutamic acid's amide oxygen (II) were synthesized using Merrifield method of solid phase peptide synthesis.
Synthesis of tritium labelled DSP 4, a selective noradrenaline neurotoxin
Authors: Sahlberg Christer , Gawell Lars 
Published: October 2006

AbstractDSP 4 (N‐(2‐Chloroethyl)‐N‐ethyl‐2‐bromobenzylamine, 1) is a neurotoxin, selective for neuronal noradrenaline (NA). Tritium labelled DSP 4 (4) with a specific activity of 105 mCi/mmol was prepared. The key step in the synthesis is a reduction of the aminoester 2 with activatated sodium boro [3H]hydride thus forming the alcohol 3.
Synthesis of 1,2,3,4‐tetrahydronaphthalene‐1‐13C, naphthalene‐1‐13C, and 1‐naphthalenol‐1‐13C
Authors: Pickering R. E. , Bymaster D. L. , Eisenbraun E. J. 
Published: October 2006

AbstractThe synthesis of 1,2,3,4‐tetrahydronaphthalene‐1‐13C, naphthalene‐1‐13C, and 1‐naphthalenol‐1‐13C in 98, 81, and 82% overall yields respectively from 4‐phenylbutanoic‐1‐13C acid is described.
Synthesis of 1,3,5‐TRI(nitro‐15N)‐1,3,5‐hexahydrotriazine, RDX‐(15NO2)3
Authors: Sitzmann Michael E. 
Published: October 2006

AbstractThe synthesis of 1,3,5‐tri(nitro‐15N)‐1,3,5‐hexahydrotriazine, RDX‐(15NO2)3, by nitrolysis of 1,3,5‐triacetyl‐1,3,5‐hexahydrotriazine is described. A method for recovery of the nitrogen‐15 labelled nitric acid not consumed in the nitrolysis is also provided.
Synthesis of malondialdehyde‐1‐2H and malondialdehyde‐1,3‐2H2
Authors: Basu Ashis K. , Marnett Lawrence J. 
Published: October 2006

AbstractTwo synthetic routes for deuterium labelling of 1,1,3,3‐tetraethoxypropane, the precursor of the ubiquitous natural compound malondialdehyde, are described. In one scheme, deuterium is incorporated in ethyl vinyl ether by metalation with t‐butyllithium followed by quenching with 2H2O. The conversion of the deuterated ether to monodeuterated tetraethoxypropane, however, proceeds with an overall yield of only ˜5%. As an alternative route, we have metalated the bis‐1,3‐propylene dithioacetal of malondialdehyde which undergoes excellent deuterium incorporation (92%). In addition, the latter method allows isotopic labelling of either one or two deuterium(s) /molecule. Hydrolysis of the deuterated dithioacetal to the corresponding tetraethoxypropane can be best effected by refluxing with HgO(red) /HgCl2/BF3. etherate in the presence of CH(OC2H5)3/C2H5OH. The overall yield of the method is 48%.
A remote system for the routine production of oxygen‐15 radiopharmaceuticals
Authors: Welch Michael J. , Kilbourn Michael R. 
Published: October 2006

AbstractThe details of the construction and operation of a remote, automated system for the production of oxygen‐15 labeled radiopharmaceuticals are described. This system routinely provides oxygen‐15 labeled oxygen, carbon monoxide, and water directly to the PET imaging facility, in quantities and purities suitable for human studies.
Synthesis of DL‐[2‐13C, 15N]aspartic acid
Authors: Baxter Robert L. , Abbot Elaine M. 
Published: October 2006

AbstractA synthesis of the title compound from [13C]paraformaldehyde and [15N]ammonium chloride via ethyl 2‐(1, 3‐[2‐13C]dithianyl) acetate 3a is described. Ethyl[3‐13C]3‐oxopropanoate derived in situ from 3a was converted by a stepwise strecker procedure to DL‐[2‐13C, 15N]aspartic acid 7a.
Synthesis of [2‐13C]quinoline and [3‐13C]quinoline
Authors: Baldwin Michael A. , Langley G. John 
Published: October 2006

Abstract[2‐13C]Quinoline and [3‐13C]quinoline were synthesised by a five‐step process starting from isatin. Acetylation of isatin with acetyl chloride labelled in either the 1‐ or 2‐position, was followed by the pfitzinger reaction to give 2‐hydroxy‐4‐quinoline carboxylic acid labelled in the 2‐or 3‐position. Decarboxylation by pyrolysis was followed by chlorination and reduction to the labelled quinolines. The overall yield was approximately 20%
Synthesis of15N‐labelled urea and methylenediurea
Authors: Murray Thomas P. , Austin Ernest R. , Howard Robert G. , Jones G. T. 
Published: October 2006

AbstractA new technique was developed for the large‐scale synthesis of15N‐labelled urea at low enrichment levels. The synthesis is based on nucleophilic displacement of the phenoxide ion from phenyl carbonate and uses anhydrous ammonia as the nucleophile. In previous reports a copper catalyst was used; however, in this study it was found that the copper resulted in product decomposition and tar formation, which makes product purification difficult. A novel set of reaction conditions was developed: no catalyst was used, and no product decomposition or tar formation occurred. The reaction product was easily purified, and consistently high yields of15N‐labelled urea were obtained.15N‐labelled methylenediurea was prepared by the dilute solution reaction of formalin with15N‐labelled urea. The methodology developed for the reclamation of unreacted urea resulted in minimum loss of labelled urea.High performance liquid chromatography has been used to determine the chemical purity of both urea and methylenediurea.
Synthesis of tritium and carbon‐14 labeled timefurone
Authors: Hsi Richard S. P. , Gammill Ronald B. , Daniels Edward G. 
Published: October 2006

AbstractTimefurone (1), a methyl thioether analogue of khellin (2), was labeled with tritium at the C‐2 position and with carbon‐14 at the C‐5 position for conducting in vivo biotransformation studies with 1. Tritium labeled 1 was prepared by lithiating and tritiating a silyllated derivative of khellinone (3) at C‐2, followed by converting the labeled khellinone into 1. Carbon‐14 labeled 1 was obtained by first dismantling the pyrone ring of khellin, followed by reconstruction of the ring with incorporation of carbon‐14 into the carbonyl position.
Synthesis of L‐[1‐13C]isoleucine via amidocarbonylation
Authors: Yuan Sun‐Shine , Ajami Alfred M. 
Published: October 2006

AbstractCobalt catalyzed amidocarbonylation of 2‐methylbutanal with [13C]carbon monoxide gave N‐acetyl‐D, L‐[1‐13C]alloisoleucine and N‐acetyl‐D, L‐[1‐13C]alloisoleucine and N‐acetyl‐D, L‐[1‐13C]isoleucine. The former was separated by crystallization from acetone and resolved by renal acylase I to give L‐[1‐13C]alloisoleucine (1) and N‐acetyl‐D‐[1‐13C]alloisoleucine (2). Then 2 was epimerized and resolved to produce L‐[1‐13C]isoleucine (3). The crystallization mother liquor was selectively resolved by Aspergillus acylase to yield 3.
Synthesis of α,β‐DI[3H]–2–fluoro–L–histidine
Authors: Takahashi Kazuyuki , Kirk Kenneth L. , Cohen Louis A. 
Published: October 2006

AbstractThe potent antimetabolite, 2‐fluoro‐L‐histidine, has been synthesized from 2‐fluoroimidazole with nonexchangeable 3H labeling in the side chain. 2‐Fluoro‐4‐iodoimidazole was N‐tritylated, was subjected to metal‐halogen exchange with n‐butyllithium, and the carbanion formylated with DMF. The imidazole‐4‐aldehyde was condensed with hippuric acid, the azlactone was solvolyzed with methanol, and the trityl group was removed by selective reduction with PtS2. The resultinq 2‐fluoro‐α‐benzamidoacrylic ester was reduced with tritium gas and the blocking groups were removed successively with base and with acylase I to produce the L‐enantiomer of the free amino acid analogue.
Synthesis of 2,4‐diphenyl‐5‐ethoxycarbonyl‐1‐heptadeuterated isopropyl‐2‐imidazoline
Authors: Bonnier M. , Marsura A. , Luu‐Duc C. 
Published: October 2006

AbstractThe synthesis of the title compound is described from heptadeuterated isopropyl alcohol in six steps. Overall yield obtained was 6%.
Syntheses of protoporphyrin‐IX regioselectively carbon‐13 labelled at the alpha‐vinyl carbons
Authors: Smith Kevin M. , Fujinari Eugene M. 
Published: October 2006

AbstractA method for transformation of readily available beta‐vinyl 99% carbon‐13 enriched derivatives of protoporphyrin‐IX dimethyl ester (3‐5) into the less accessible alpha‐vinyl labelled isomers (6‐8) is described. The procedure involves thallium(III) promoted vinyl carbon rearrangement, and proceeds through 2,2‐dimethoxyethyl (e.g. 10), formylmethyl (e.g. 11), 2‐hydroxyethyl (e.g. 12) and 2‐chloroethyl (e.g. 13) porphyrins; the rearranged vinyl groups are regenerated from 2‐chloroethyl in the last step by treatment with base. No evidence of vinyl carbon scrambling in the sequence is observed, and spectroscopie data of the products are given.
Syntheses of 2‐(diacetoxymethyl‐14C)‐5‐nitrofuran and carbon‐14 labeled nitrofurazone
Authors: Duclos Richard I , Hoener Betty‐Ann 
Published: October 2006

AbstractA new method for the microscale syntheses of carbon‐14 labeled 5‐nitrofuran derivatives of high specific activities was developed. Ethyl 2‐furancarboxylate‐carboxy‐14C (3) was prepared in an improved yield from Ba14CO3. 2‐Furancarboxaldehyde‐formyl‐14C (5) was prepared by reduction of the ester 3 followed by γ‐MnO2 oxidation of 2‐(hydroxymethyl‐14C)furan (4). 2‐(Diacetoxymethyl‐14C)‐5‐nitrofuran (7), an immediate precursor of many radiolabeled 5‐nitrofuran drugs, was prepared in a new two‐reaction one‐flask procedure from 2‐furancarboxaldehyde‐formyl‐14C (5) in 7.3% overall radiochemical yield from Ba14CO3. Carbon‐14 labeled nitrofurazone (8) was then prepared from 7.
Methodes Generales de Syntheses de Composes Lineaires ω‐Trideuteries
Authors: Bouloussa O. , Denhez J. P. , Dizabo P. 
Published: October 2006

AbstractNous proposons dans ce travail deux méthodes générales de synthése de composés trideutériés sur le méthyle terminal d'une chaine aliphatique. Dans les deux cas. l'hydrolyse de l'un des groupements esters constitue la premiére étape du schéa réactionnel. L'acide ester obtenu est transformé i) en aldéhyde ester; une réaction de Wittig conduit au vinyl ester. Le groupement ester est réduit d'abord en alcool 1‐2H2, puis par l'intermédiaire du mésylate en ω‐2H3 l‐alcene. L'oxydation de ce composé donne l'acide ω‐2H3. ii) en alcool ester. La fonction alcool est protégée par le dihydropyranne et le groupement ester est traité comme ci‐dessus. On obtient ainsi l'alcool ω‐2H3.