bluuebunny/crossref_metadata_2025_split huggingface dataset:
14C‐synthesen biologisch interessanter p‐substituierter aryläthan‐körper
Authors: Schiefer S. , Kindl H. 
Published: October 2006

Abstractp‐Methoxyphenylacetaldehyde oxime‐1−14C and p‐hydroxyphenylacetaldehyde oxime‐1−14C were synthesized from the corresponding arylnitroethenes. The radioactive carbon atom was introduced by the condensation of p‐substituted benzaldehydes with nitromethane−14C. Using preparative thin layer chromatography a convenient procedure is described leading to products with high specific activity. Under certain conditions the reduction of arylnitroethenes yielded predominantly the saturated nitrocompounds. Labelled tyrosol and its derivatives were obtained from the corresponding acids by reduction with lithium aluminium hydride.
Radiochemical synthesis part II The preparation of 14C‐labeled juvenile hormone
Authors: Hafferl W. , Zurflüh R. , Dunham L. 
Published: October 2006

Abstractdl‐2−14C‐Juvenile hormone was prepared from 2−14C‐trimethyl phosphonoacetate, sodium hydride and cis‐9,10‐oxido‐6‐ethyl‐10‐methyldodec‐5(t)‐en‐2‐one in dry tetrahydrofuran and purified by gas chromatography. The reaction conditions were established by synthesizing the trans‐isomer of juvenile hormone. The specific activity of labeled hormone was determined by mass spectroscopy.
Enzymic preparation of specifically 14C and 3H labelled shikimic acids
Authors: Scharf K.‐H. , Zenk M. H. 
Published: October 2006

AbstractD‐Shikimic acids 1−14C, 6−14C and 7‐(carboxyl) 14C have been biosynthetically prepared with specific activities of about 25 mCi/mmole and with overall yields of 45% based on pyruvate 3,2 or 1−14C as the respective starting materials. A crude cellfree homogenate of E. coli 83–24 was used to catalyze the condensation of phosphoenolpyruvate−14C with unlabelled erythrose‐4‐phosphate to give shikimic acid. Phosphoenolpyruvate−14C was synthesized from pyruvate−14C and ATP by the action of phosphoenolpyruvate‐synthase. Erythrose‐4‐phosphate 1,2,3,4−14C and erythrose‐4‐phosphate‐4‐T was prepared from glucose‐U−14C and glucose‐6‐T via enzymatic phosphorylation to labelled glucose‐6‐phosphate and subsequent lead tetraacetate oxidation. Condensation of labelled E‐4‐P with unlabelled PEP gave rise to shikimic acid‐2,3,4,5−14C and 2‐T.
The synthesis of 1. 2. 3. 4‐tetrahydro‐(7‐3H) naphthalene and (7‐3H) naphthalene labeled with 14C in the 1‐or 2‐position
Authors: Den Hollander W. , Van Der Jagt P. J. , Van Zanten B. 
Published: October 2006

AbstractProcedures are given for the preparation of (2‐14C), (7‐3H) naphthalene, (1‐14C), (7‐3H) naphthalene, 1. 2. 3. 4‐tetrahydro‐(2‐14C), (7‐3H) naphthalene and 1. 2. 3. 4‐tetrahydro (1‐14C), (7‐3H) naphthatene. Starting with 14 CO2 the 1‐14 C‐labeled compounds were prepared in a 4‐ or 5‐ a tep synthesia in an overall yield of 56 or 44% respectively and the 2‐14 C‐labeled compounds in a 8‐ or 9‐ atep synthesis in an overall yield of 52 or 39% respectively. The specificity of the 14 C‐labeling was in all cases better than 97%.
Self ‐ radiolysis of tritiated compounds : IV ‐ unsaturated fatty acid esters
Authors: Colosimo M. , Guarino A. 
Published: October 2006

AbstractThe self‐radiolysis of methyl oleate‐9, 10‐T has been studied under different conditions of storage, i. e. under vacuum, in solution of benzene, of n‐pentane, and of cyclohexene.The influence of the storing conditions on the total yields of decomposition, as well as on the different self‐radiolysis products formed, is discussed taking into account the processes and mechanisms observed in the radiation chemistry of this, and similar compounds.
Synthesis of carbon ‐ 14 labeled 1‐β ‐D‐arabinofuranosylcytosine
Authors: Hsi Richard S. P. 
Published: October 2006

AbstractThe synthesis of carbon‐14 labeled 1‐β‐D‐arabixofuranosylcytosine and its hydrochloride salt is described. The products, preyared in four steps from barium carbonate‐ 14C, are labelea in the C‐2 position of the pyrimidine ring.
Synthesis of [8‐14C]. N6‐(Δ2‐isopentenyl ) adenosine
Authors: Fleysher M. H. 
Published: October 2006

AbstractN6 ‐ (Δ2 ‐isopentenyl) adenosine, known as IPA or IPAdo, is a normal component of t‐RNA which has growth atimulatory effects in plants and growth inhibitory effects in mammalian cells, including human leukemia. 8‐14C‐IPA was synthesised' by alkylating 8‐14C adenosine with Δ2‐isopentenly bromide. The purity of the radioactive product was greater than 99%. A procedure was devised for isolating this compound and preserving its purity.
The use of diborane and deuterodiborane in the synthesis of isotopically labeled amines
Authors: Marshall Frederick J. , McMahon Robert E. , Lacefield William B. 
Published: October 2006

AbstractThe use of diborane has facilitated the preparation of several amines labeled with carbon‐14 or nitrogen‐15 by reduction of the corresponding labeled nitrile or amide. Its use was particularly advantageoue in the presence of aromatic halide substituents. Deuterodiborane, formed in situ from sodium borodeuteride and dimethyl sulfate, has been shown to be useful in the synthesis of 1, 1‐dideuteroamines.Amines prepared in this study include nortriptyline labeled with nitrogen‐15, deuterium or both,; 2‐(o‐chlorophenoxy) ethyl‐N‐cyclopropylamine as the 1‐14C‐derivative and as the 1, 1‐dideutero derivative; 2‐(2, 4‐dichloro‐6‐phenylphenoxy) ethyl‐1‐14C amine and its 2‐chloro‐6‐phenyl analog; and 3‐aminomethyl14C‐pyridine.
Resolution of racemic acyl‐amino acids‐ 14C by water‐insoluble hog kidney acylase
Authors: Johannsen B. , Syhre R. , Berger R. 
Published: October 2006

AbstractFor the purpose of continous resolution of racemic N‐acyl‐amino acids‐14C conditions for the preparation and utilization of water‐insoluble hog kidney acylase (E. C. 3. 5. 1. 14) were investigated, A stable, highly active water‐insoluble acylase was easily prepared by linking the enzyme to DEAE‐Sephadex A‐50 in Tris‐HCL‐buffer, μ 0.045; at pH 7. 1.
Purification of tritiated phenacetin and N‐acetyl‐p‐aminophenol
Authors: Singh H. P. , Gault M. H. 
Published: October 2006

AbstractPhenacetin and N‐acetyl‐p‐aminophenol (NAPA) tritiated by catalytic exchange (1), were quite impure as purchasedNew England Nuclear Corp., Boston, Mass. 02118.
No previous reports on purification of these radioactive compounds could be found, although there are reports of separation of phenacetin or NAPA by chromatography (2, 3). Purificaion was carried out in two steps : gel filtration with Sephadex G‐10, followed by thin layer chromatography on silica gel.
The synthesis of 14C‐trans‐3‐methyl‐2‐hexenoic acid labeled in various positions
Authors: Rabinowitz Joseph L. , Zanger Murray 
Published: October 2006

AbstractThe Emmons reaction was used for the synthesis of 14C‐trans‐3‐methyl‐2‐hexenoic acid. This compound is found in human sweat. 1‐14C‐2‐pentanone was prepared by the reaction at room temperature of 14C‐methyl‐magnesium iodide and butyronitrile.
Synthesis of 6‐(D‐α‐aminophenylacetamido‐1‐14C)‐penicillanic acid
Authors: Valcavi U. 
Published: October 2006

AbstractThe synthesis of 6‐(D‐α‐aminophenylacetamido‐1‐14C)‐ penicillanic acid (V) is described. Benzaldehyde (I) was converted with sodium cyanide‐14C and ammonium chloride into D, L‐α‐aminophenylacetic acid‐1‐14C (II), from which the D‐form was separated with D‐camphorsulfonic acid. The D‐α‐aminophenylacetic acid‐1‐14C (III) was converted, with ethyl acetoacetate into enaminoderivative (IV), which, by means of reaction with ethyl chlorocarbonate and with triethylammonium salt of 6‐aminopenicillanic acid, gave 6‐(D‐α‐aminophenylacetamido‐1‐14C)‐penicillanic acid (V).
Preparation of 6‐azauracil‐5‐3H and 6‐azauridine‐5‐3H of high molar activity
Authors: Filip Jiri , Skoda Jan , Hradec Hynek 
Published: October 2006

AbstractCatalytic reductive dehalogenation of 5‐bromo‐6‐azauracil with carrier‐free tritium led to 6‐azauracil‐5‐3 H of a molar activity of 19.0 Ci/mmole. The reaction conditions for the catalytic reductive dehalogenation were examined in tracer experiments. Microbial transformation was used for the preparation of 6‐azauridine‐5‐3 H from 6‐azauracil‐5‐3 H. 6‐Azauridine‐5‐3‐ H was prepared at a molar activity of 18.8 Ci/mmole. In both compounds the stability of tritium was investigated in an aqueous medium at 100°C.
Synthesis of 8‐chloro‐6‐phenyl‐4H‐s‐triazolo [4,3‐a] [1,4] benzo‐diazepine‐1‐14C
Authors: Hayashi Nobuyoshi , Shinozaki Kazuo , Kato Shinji , Meguro Kanji , Kuwada Yutaka 
Published: October 2006

Abstract8‐Chloro‐6‐phenyl‐4H‐s‐triazolo [4,3‐a] [1,4] benzodiazepine (D‐40TA)‐1‐14C (V‐14C) was synthesized by the reaction of formic acid‐14C with 7‐chloro‐2‐hydrazino‐5‐phenyl‐3H‐1, 4‐benzodiazepine in the presence of N,N′‐carbonylbis (2‐methylimidazole). The overall radio‐chemical yield from formic acid‐14C was 57.8%.
Preparations du Trans‐P‐Methoxyphenyl‐1‐propene‐1‐14C‐3 (Trans Anethole 14C‐3) et du trans‐anethole (Noyau 14C‐U)
Authors: Herbert Michel , Pichat Louis , Langourieux Yves 
Published: October 2006

AbstractMethyl iodide 14C is reacted with lithium p‐methoxy phenylacetylenide to give with a 85% yield 1‐p‐methoxy‐phenyl‐1‐propyne‐3‐14C.Reduction of the latter with LiAlH4 leads to a mixture of trans anethole‐3‐14C (85%) and cis anethole (15%) with a 55% yield. After preparative gas chromatography pure trans anethole‐3‐14C is isolated with an overall yield of 20% based on methyl iodide 14C.Benzene 14C (U) is brominated into bromobenzene 14C (U) which by copper catalysed alcaline hydrolysis gives phenol 14C (U). Methylation of the latter leads to anisole 14C (U).Gattermann reaction with the latter gives a mixture of o‐and p‐méthoxy‐benzaldehyde 14C (U) in a 80% yield from which pure para isomere is isolated by colwmn chromatography with a 42% yield based on anisole 14C (U). Treated with ethyl magensium iodide p‐methoxybenzaldehyde leads to 1‐p‐methoxy‐phenyl‐1‐propanol (ring 14C‐U) the dehydration of which by heating with Al2O3 gives a mixture of trans anethole (ring 14C‐U) (80%) and cis anethole (ring 14C‐U) (20%). After preparative gas chromatography pure trans anethole (ring 14C‐U) is isolated with an overall yield of 5% based on barium carbonate 14C.
Preparation of tritium‐labelled α‐dihydrograyanotoxin II
Authors: Soeda Yoshinori 
Published: October 2006

Abstractα‐Dihydrograyanotoxin II has been labelled with tritium at the C‐10 and C‐19 positions by catalytic hydrogenation of grayanotoxin II. Pd‐catalyzed reduction in tetrahydrofuran produced the α‐form exclusively. The compound was obtained with specific activity 1.21 Ci/mmole and with 99% radio‐chemical purity.
The synthesis of 14C‐diethylamine and lysergic acid diethylamide
Authors: Barnes R. D. 
Published: October 2006

AbstractThe preparation of lysergic acid [14C1]‐diethylamide is described. [14C1]‐Diethylamine was synthesised in three steps; sodium [14C1]‐acetate was treated with thionyl chloride giving [14C1]‐acetyl chloride which was reacted with ethylamine to give N‐ethyl‐[14C1]‐acetamide. Reduction of this amide with lithium aluminium hydride gave [14C1]‐diethylamine which on treatment with a lysergic acid‐imidazole complex gave the required product.
Synthesis of labelled organic compounds for solid state diffusion studies
Authors: Lockhart N. C. 
Published: October 2006

AbstractThe synthesis and purification of suitable radioactive tracers for organic solid state self diffusion experiments is described. Particular attention is paid to the isotope effect which requires two tracers containing different radioactive isotopes, and with as large a mass difference as possible. The latter is accomplished by incorporating a stable isotope in one of the tracers. Active preparations of adamantane, dl‐camphene, bromopentamethyl‐ethane, and hexamethylethane are reported.
Route to the tritiation of carbon atom‐9 of carcinogenic fluorenylhydroxamic acids
Authors: Gutmann H. R. , Bell P. 
Published: October 2006

AbstractThe selective tritiation of the methylene carbon atom of the carcinogens, N‐fluoren‐3‐yl‐and N‐fluoren‐1‐ylacetohydroxamic acid, has been investigated. The synthesis of N‐[9‐3H]fluoren‐3‐ylacetohhydroxamic acid involves hydrogenolysis of 3‐aminofluoren‐9‐one to [9‐3]fluoren‐3‐amine with LiAl3H4‐A1C1‐. The tritiated amine is oxidized to 3‐nitro‐[9‐3H]fluorene with m‐chloroperoxybenzoic and the labeled nitro compound is partially hydrogenated to the 3H‐hydroxamic acid with 10% Pd–C catalyst in presence of acetic anhydride and triethylamine or dimethylaniline. N‐[9‐3H]fluoren‐1‐ylacetohydroxamic acid may be obtained from 1‐aminofluoren‐9‐one by the same procedure. However, N‐[9‐3H]fluoren‐2‐ylacetohydroxamic acid cannot be prepared in this way because reduction of 2‐aminofluoren‐9‐one with LiA1H4‐A1C13 does not proceed beyond the alcohol, 2‐aminofluoren‐9‐ol.
Synthese de L'Acide NN Dichloro‐2, Ethyl, p Amino Phenyl‐4, Butyrique (Chloraminophene) Marque au 14C
Authors: Moreau Jean , Madelmont Jean‐Claude 
Published: October 2006

AbstractL'acide NN dichloro‐2, ethyl p amino phényl‐4, butyrique est marqué par 14C en trois positions différentes:

sur le carbone portant la fonction carboxylique à partir de K14CN.
uniformément sur les quatre carbones du groupement dichloroéthyl à partir d'oxyde d'éthylène radioactif.
sur le carbone placé en α de la fonction carboxylique à partir de K14CN.
Syntheses of 14C‐labeled cinnamic, mandelic, phenylacetic, phenylglyoxylic, and phenylpyruvic acids
Authors: Larsen Peder Olesen , Wieczorkowska Elizabeth 
Published: October 2006

AbstractSyntheses are described for 3′‐carboxyphenylpyruvic acid‐2‐C14, 3′‐carboxy‐4′‐hydroxyphenylpyruvic acid‐2‐C14, (E)‐3′,‐carboxycinnamic acid‐2‐C14, (E)‐3′‐carboxy‐4′‐hydroxycinnamic acid‐2‐C14, 3′‐carboxyphenylacetic acid‐1‐C14, 3′‐carboxy‐4′‐hydroxyphenylacetic acid‐1‐C14, 3′‐carboxymandelic acid‐1‐C14, 3′‐carboxy‐4′‐hydroxymandelic acid‐1‐C14, 3′‐carboxyphenylglyoxylia acid‐1‐C14, and 3′‐carboxy‐4′‐hydroxyphenylglyoxylic acid‐1‐C14.
Synthesis of 14C‐labelled (+)‐limonene
Authors: Noda K. , Matsuda T. , Ishikura Y. 
Published: October 2006

Abstract14C‐labelled (+)‐limonene was conveniently prepared by the Wittig reaction of (+)‐1‐methyl‐4‐acetylcyclohexene with methyl‐14C‐triphenylphosphonium iodide.
The synthesis of 14C‐labelled (U) 2,4,2′,4′‐tetrachlorobiphenyl
Authors: Melvas B. 
Published: October 2006

AbstractIt was possible to prepare 14C‐2,4,2′,4′‐tetrachlorobiphenyl with a purity of 98% by condensation of 14C‐1‐chloro‐2,4‐dinitro‐benzene to yield 14C‐2,4,2′,4′,‐tetranitrobiphenyl and substitution of the nitro groups by chlorine with thionyl chloride. The synthesis must be carried out on a small scale for two reasons‐the cost and the hazards with radioactive material. The synthesis described here was performed on a 10mg scale. Both of the chemical reactions were performed in sealed ampoules and the overall yield varied between 30 and 40%.
The synthesis of 14C‐safrole, myristicin and elemicin labeled in the allyl side chain
Authors: Walker M. , McKinney J. , Oswald E. 
Published: October 2006

AbstractThe preparation of 1‐[ (3′‐14C)‐Allyl]‐3,4‐methylene dioxy‐,1‐[(3′‐14C)‐allyl]‐3‐methoxy‐4,5‐methylene dioxy‐, and 1‐[(3′‐14C)‐allyl]‐3,4,5‐trimethaoxy benzenes is described. The 14C‐label was introduced into the 3′‐carbon of the allylic side chain via the Wittig reaction.
Photo‐oxidation in the synthesis of17O and 18O labelled compounds: Synthesis of xanthone‐18O1
Authors: Pownall Henry J. 
Published: October 2006

AbstractIt it shown that the photo‐oxidation of aromatic molecules containing an active methylene group can be used to introduce isotopic oxygen. Photo‐oxidation of xanthene results in the formation of xanthone with the oxygen label appearing in the product at the carbonyl group. In this way, 100% enrichment can be realized. A brief discussion of other systems to which this method may be extended is also given.
Preparation of fluothane‐82Br by means of recoil labeling
Authors: Hoizumi Kiyoshi , Mogi Terutomi , Kudo Hiroshi 
Published: October 2006

AbstractFluothane (1, 1, 1‐trifluoro‐2‐chloro‐2‐bromoethane) is a well known anesthetic, and its labeled compound has been much required for the biological investigation. The method was studied to prepare fluochane‐82Br by means of recoil labeling. More than 20 organic species labeled with bromine‐82 evolved in neutron‐irradiated fluothane. From such the complicated system, however, fluothane‐82Br was purely obtained by the gas chromatographic separation. Under the optimum conditions, the radiochemical yield of fluothane‐82Br contributed to 38%.When 200 μl of the target material was irradiated with neutrons to the total neutron dose (nvt) of 3.4 × 1016n/cm2, the radioactivity of 82Br‐labeled fluothane isolated almost quantitatively was about 2.7 mCi.
Synthesis of carbon‐14 labeled diphenylhydantoin and its major metabolite 5‐(p‐hydroxyphenyl)‐5‐phenylhydantoin (HPPH) in 70 minutes
Authors: Stavchansky S. , Kostenbauder H. B. 
Published: October 2006

AbstractA simple and convenient method for the synthesis of carbon‐14 labeled diphenylhydantoin (DPH) (I) and its major metabolite 5‐(p‐hydroxyphenyl)‐5‐phenylhydantoin (HPPH) (II) in 70 minutes is described. This synthesis allows incorporation of carbon‐11‐11 (physical half‐life 20 minutes) into these molecules. Incorporation of short‐lived isotopes into drug molecules provides a vastly expanded potential for study of in vivo distribution of drugs and development of tumor specific agents.
NEW Possibilities of preparative synthesis of radioactive nucleotides V. Enzyme synthesis of tritium labelled uridine 5′‐triphosphate in high yield
Authors: Filip J. , Bohacek L. , Vesely J. , Cihak A. 
Published: October 2006

AbstractGrowth of Escherichia coli B in the presence of sub−bacteriostatic concentration of various compounds results in the enhancement of activity of enzymes catalyzing the transformation of uridine to its 5′‐phosphates. Partially purified extracts of E. coli cultivated in the presence of 1×10−5M 5‐azacytidine were applied for the preparative synthesis of tritium‐labelled uridine 5′‐triphosphate. Yield of the newly formed nucleotide was about 90% and was higher during the short‐term incubation using enzyme extract from the treated cells than that from controls.
Sterol metabolism, XXXI. Synthesis of the epimeric [24‐3H] cholest‐5‐ENE‐3β, 24‐diols
Authors: Lin Yong Yeng , Smith Leland L. 
Published: October 2006

AbstractA synthesis of [24‐3H] (24S)‐cholest‐5‐ene‐3β, 24‐diol (cerebrosterol) in 12.1% radiochemical yield and of its 24‐epimer has been achieved by sodium borotritide reduction of 3β‐hydroxycholest‐5‐en‐24‐one derived from 3β‐hydroxychol‐5‐enic acid by an improved procedure. The epimeric 3β, 24 diols were separated as the dibenzoate esters, for which circular dichroism data are presented in support of the assigned absolute stereochemistry.
Synthesis of 5α‐pregnane‐3β,20α‐diol and of 5α‐pregnane‐3α,20α‐diol labelled specifically at the 20β‐position
Authors: Baillie T. A. , Herz J. E. , Sjövall J. 
Published: October 2006

AbstractA convenient synthesis of 5α‐[20β‐2H]pregnane‐3α,20α‐diol and 5α‐[20β‐2H]pregnane‐3β,20α‐diol from 3β‐hydroxy‐5α‐pregn‐16‐en‐20‐one is described. The reaction products are characterized by combined gas chromatography‐mass spectrometry.
The synthesis of 32P and 14C‐labelled o,S‐dimethyl phosphoroamidothioate
Authors: Lubkowitz J. A. , Horler D. F. , Baruel J. 
Published: October 2006

AbstractO,S‐Dimethyl phosphoroamidothioate has been synthesized with 32P and with 14C in the methoxy and the S‐methyl group. Phosphorus trichloride was reacted with sulfur giving phosphorrus thiochloride. The latter was reacted with methanol in the presence of acridine and calcium oxide yielding O‐methyl phosphorodichloridothioate. Isomerization at 100°C gave S‐methyl phosphorodichloridothioate. Finally, treatment with methanol and ammonia gave O,S‐dimethyl phosphoroamidothioate. 32P‐labelled phosphorus trichloride and 14C‐methanol were appropriately introduced to yield the desired compound.The intermediates and final product were characterized by NMR, mass spectra and TLC. Products were purified by solvent partition (S‐methyl labelled) and anion exchange chromatography (32P‐labelled). Radiochemical purity was determined by TLC. Liquid Scintillation counting was used to determine specific activities. The 32P‐labelled compound had a specific activity of 163 μCi/mM while the 14C‐methoxy and S‐methyl compounds had specific activities of 86 and 68 μCi/mM respectively.
Synthesis of [3–12′,4′,5′‐triethoxybenzoyl‐(carbonyl‐14C)] propionic acid (AA‐149‐14C)
Authors: Hayashi Nobuyoshi , Toga Tadashi , Murata Tadakazu 
Published: October 2006

AbstractThe synthesis of 3‐[ 2′,4′,5′‐triethoxybenzoyl‐(carbonyl‐14C)]‐propionic acid (VII) is described. Chloroacetonitrile‐14C (IV) was prepared from chloroacetic‐1‐14C acid (I) according to the well‐known procedure. IV was reacted with 1,2,4‐triethoxybenzene in the presence of ZnCl2 and HCl, and the resulting ketoimine hydrochloride was hydrolyzed to 2′,4′,5′‐triethoxyphenacyl‐(carbonyl‐14C) chloride (V) in 66.5% yield. VII was obtained in 66% from ethyl [2′,4′,5′‐triethoxyphenacyl‐(carbonyl‐14C)] malonate (VI) which had been prepared in 57% from V by an application of malonic ester synthesis. The overall radiochemical yield from I to VII was 11.2%.
Biosynthetic preparation of 11C‐labelled galactose, glycerol and mannitol
Authors: Palmer A. J. , Goulding R. W. 
Published: October 2006

Abstract11C‐labelled galactose, glycerol and mannitol have been prepared biosynthetically from 11C‐labelled carbon dioxide using species of marine algae. Following biosynthesis the labelled compounds are rapidly extracted from the algae and purified by liquid chromatography.
Syntheses de Pyrrolidines Deuteriees
Authors: Rogic D. , Lautie M. F. , Dizabo P. , Leitch L. C. 
Published: October 2006

AbstractCinq pyrrolidines di ou tétradeutériées ont été préparées soit par réduction de la cétone correspondante (dideutério‐2,2 pyrrolidine), soit à partir du dérivé N nitrosé après échange en milieu basique (tétradeutério‐2,2,5,5 pyrrolidine) soit enfin par cyclisation d'une chaǐne aliphatique marquée en position souhaitée (dideutério‐3,3, tétradeutério‐2,2,3,3 et tétradeutério‐3,3,4,4 pyrrolidines).
The synthesis of 5‐hydroxyindole‐3‐(‐2‐D2‐acetic acid) and α,α′,β,β′‐D4‐5‐hyoroxytryptamine
Authors: Beck Olof , Sedvall Göran 
Published: October 2006

AbstractDeuterium Labelled 5‐hydroxyindole‐3‐acetic acid and 5‐hydroxy‐tryptamine have been sythesized by a modification of the procedure previously described by Ek and Witkop (9) for the nondeuterated analogues. The deuterium is introduced by a solvent exahange reaction and by reduction with lithium aluminium deuteride. The isotopic yield was > 99%.
Synthesis of a tritium labelled pyrrolizidine alkaloidisenecioyl retronecine
Authors: Hsu I. C. , Allen J. R. 
Published: October 2006

AbstractRetronecine (7β‐hydroxy‐1‐hydoxymethyl‐1,2‐dehydro‐8α‐pyrrolizidine) (II) which is prepared from the hydrolysis of monocrotaline (I) was oxidized with manganese dioxide in the presence of potassium cyanide to methyl 1,2‐dehydro‐7β‐hydroxy‐8α‐pyrrolizidine‐1‐carboxlate (III). Retronecine (II') was 3H labelled at the 1 methyl proton by the reduction of III with LiAl3H4. The semi‐synthetic pyrrolizidine alkaloid disenecioyl retronecine (Di‐3,3‐dimethylacrylic acid ester of retronecine). having a high specific activity. was prepared by the acylation of 3H retronecine (II') with senecioyl chloride (3,3‐dimethylacryloyl chloride).
Dimethyl trisulfide‐d6
Authors: Harpp David N. , Back Thomas G. 
Published: October 2006

AbstractDimethyl trisulfide‐d6 was prepared in high purity and isotopic content. Methane thiol‐d3 was generated by the base decomposition of the appropiate isothiouronium salt. Oxidation was mediated via bis‐phthalimido sulfide with imidazole catalyst.