bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthese de l'acide acetoxy‐2 trifluoromethyl‐4 benzoique [noyau 14C‐U] OU “triflusal [noyau 14C‐U]”
Authors: Noel J. P. , Pichat L. , Rimbau V. , Forn J.
Published: October 2006

Synthesis of 2‐acetoxy 4‐trifluoromethyl benzoīc acid [ring U ‐14C] or “[ring U‐14C] Trifusal” U14C)(Ring U‐14C) Aniline 1 was converted into (ring U‐ 14C) idobenzene 2 through the (ring U‐14C) phenyldiazonium chloride. Trifluoromethylation of 2 with iodotrifluoromethane in presence of copper gave (ring U‐14 C) trifluoromethylbenzene 3 with a 64% yield. Nitration of 3 with sodium nitrate + trifluoromethane sulfonic acid in dichloromethane gave a 86% yield of (ring U‐14C) 3‐nitro trifluoromethyl benzene 4 which was reduced by iron and HCl into the corresponding amine 5. The latter was transformed into the phenol 6 with a 85% yield by action of Cu (NO3)2 and CuO on (ring U‐14C) 3‐trifluo romethyl phenyldiazonium sulfate. Kolbe reaction of phenol 6 with carbon dioxide and K2CO3 gave 7 with a 59% yield. Acetylation of 7 gave (ring U‐14C) Triflusal 8 with a quantitative yield and a specific activity of 14 mCi/mMole14 radiochemical purity 98.5%. The overall yield from 14C barium carbonate was 10%.
Syntheses of carbon‐13 and deuterium labelled L‐tryptophan, racemic 5‐hydroxytryptophan and 5‐hydroxytryptamine (serotonin)
Authors: Saari Walfred S.
Published: October 2006

Convenient and efficient syntheses of 13C and 2H sidechain labelled L‐tryptophan, racemic 5‐hydroxytryptophan and 5‐hydroxytryptamine (serotonin) from indole and 5‐benzyloxyindole are described.
General methods for the preparation of α and/OR β deuterium labelled 6‐hydroxydopamine derivatives
Authors: Borchardt Ronald T. , Simmons John E.
Published: October 2006

A convenient synthetic method for the preparation of α and/or β deuterium‐labelled 6‐hydroxydopamines has been developed. Nitromethane was condensed with 2,4,5‐trimethoxybenzaldehyde to give 2,4,5‐trimethoxy‐α‐nitrostyrene (2). The nitroethylene side chain of 2 was reduced with sodium borodeuteride to afford β‐[2H]‐β‐(2,4,5‐trimethoxyphenyl)‐α‐nitroethane (3). A reduction with sodium borohydride in the presence of a deuterium source (e.g. EtOD) afforded mono and dideuterated α‐[2H]‐β‐ (2,4,5‐trimethoxyphenyl)‐α‐nitroethanes (9, 10). A reduction of the nitrostyrene 2 with sodium borodeuteride in EtOD resulted in the isolation of α,β‐[2H]‐β‐(2,4,5‐trimethoxyphenyl)‐α‐nitroethanes (15 and 16). Subsequent reduction of the deuterated α‐nitroethanes 3, 9, 10, 15 and 16 gave the appropriately labelled phenethylamine derivatives 5, 11, 12, 17 and 18. Removal of the phenol protecting groups afforded the deuterium labelled 2,4,5‐trihydroxyphenethylamines (6‐hydroxydopamines).
Synthesis of phencyclidine and its analogues labeled with 14C and 3H
Authors: Alme Peter , Law Francis C. P.
Published: October 2006

14C‐Labeled phencyclidine, piperidinocyclohexane carbonitrile and phenylcyclohexene were synthesized chemically from 14Clabeled bromobenzene or cyclohexanone. 3H‐Labeled N‐ethyl‐1‐phenylcyclohexylamine was prepared by reducing N‐acetyl‐1‐phenylcyclohexylamine with 3H‐lithium aluminum hydride.
Purification of [3H]‐8‐methoxypsoralen by high performance liquid chromatography
Authors: Adriaens P. , De Schrijver F. , Van Boven M. , Roelandts R. , Roets E. , Hoogmartens J.
Published: October 2006

A sample of [3H]‐8‐methoxypsoralen was purified by high performance liquid chromatography on silica gel.
Synthesis of deuterium‐labelled methylphenidate, p‐hydroxymethylphenidate, ritalinic acid and p‐hydroxyritalinic acid
Authors: Patrick Kennerly , Kilts Clinton , Breese George
Published: October 2006

The synthesis of threo‐dl‐methylphenidate (Ritalin®, 1), threo‐dl‐p‐hydroxymethylphenidate (3), threo‐dl‐ritalinic acid (2), and threo‐dl‐p‐hydroxyritalinic acid (4) with deuterium incorporated in the piperidine ring is described. These compounds were synthesized for use as internal standards for mass fragmentographic assays of methylphenidate and its metabolites. The synthetic scheme described resulted in less than 0.05% 2H0 in the piperidine ring in any of the preparations.
The preparation of carbon‐14 and tritium labelled 1‐[4‐(2‐dimethylaminoethoxy) phenyl]‐1, 2‐diphenyl‐1‐butene [ICI 46,474, tamoxifen (nolvadex)] and the separation of cis‐trans isomers 2. The synthesis of tritium labelled tamoxifen (nolvadex)
Authors: Burns J. , Richardson O. N.
Published: October 2006

The preparation of tritiated tamoxifen generally labelled, and also specifically labelled in two separate positions is described. The generally tritiated material was prepared by an acid catalysed exchange reaction which produced labelled material of low molar specific activity [4.7 mCi/mmol].

Both specifically tritiated products were derived from tritium labelled intermediates which were used in synthetic procedures to produce tritiated tamoxifen. [G‐3H]Bromobenzene was used to incorporate the label in the 1‐phenyl ring, and tamoxifen with a specific activity of 401 mCi/mmol was obtained. The reductive tritiation of a 3, 5‐dibromo precursor and subsequent synthesis gave tamoxifen with a specific activity of 19.5 Curies/ mmol.
Preparation of deuterium‐labeled nucleosides by platinum‐catalyzed exchange and reduction
Authors: Kinoshita T. , Schram Karl H. , McCloskey James A.
Published: October 2006

Selective incorporation of deuterium by platinum‐catalyzed exchange for six ribonucleosides and two 2′‐deoxyribonucleosides has been studied as a function of catalyst/substrate ratio, temperature, time and concentration. In addition to exchange of carbon‐bound hydrogens in purines, pyrimidines and pyrrolo[2,3‐d]‐pyrimidines, reactions involving D2‐saturated D2O as solvent were used to effect extensive exchange of ribose hydrogens, principally at C‐2′. Reduction‐exchange of uridine was used to prepare 5,6‐dihydrouridine‐5,5,6,6,‐d4, and 4‐amino‐5,6‐dihydro‐7‐(β‐D‐ribofuranosyl)pyrrolo[2,3‐d] pyrimidine‐2,5,5,6,6‐d5 from tubercidin. Sites and extent of deuteration were determined by mass spectrometry and proton magnetic resonance.
Synthese du SL 75.212 (Betaxolol) Marque au Carbone 14 : [Cyclopropylmethoxy‐2 Ethyl 14C‐1)‐4 Phenoxy] ‐ 1 Isopropylamino‐3 Propanol‐2
Authors: Aubert F. , Beaucourt J.‐P. , Pichat L.
Published: October 2006

The synthesis of SL‐75.212 (BETAXOLOL) labelled with carbon 14 : 1‐[4‐(2‐cyclopropyl methoxyethyl‐[1‐14C]) phenoxy]‐3‐isopropul amino‐2‐propanol : 13 was achieved by a twelve step sequence from [14C] carbon dioxide.

Carbonation with 14CO2 of the Grignard reagent 1 gave 4‐benzyloxy [carboxyl‐14C] benzoic acid: 2 (87 % yield). 2 was successively treated in diethyl ether solution with diazomethane and lithium aluminium hydride giving rise to [7‐14C] 4‐benzyloxybenzyl alcohol 4 (82 % yield). Alcohol 4 was transformed into the corresponding chloride 5 when exposed to thionylchloride in ether. 5 was condensed with NaCN in DMF to give the nitrile 6 which was hydrolysed into the acid 7 isolated in a 75% overall yield from Ba14CO3. 7 gave the alcohol 9 by successive treatments with diazomethane and LiAlH4 in ether. 9 with NaH gave the corresponding alkoxide which when condensed with bromomethylcyclopropane gave the ether 10 purified by silicagel column chromatography and isolated with an overall yield of 71 % from Ba14CO3. Hydrogenolysis of 10 gave the phenol 11. The epoxide 12 was secured by condensation with epichlorhydrin in presence of NaOH. After purification by silicagel column chromatography 10 was opened with isopropylamine leading to the target compound BETAXOLOL 13 isolated as the hydrochloride. After extensive purification by Sephadex G‐10 column chromatography, SL 75.212 [ethyl‐1‐14C] was obtained in an overall yield of 26% from barium [14C] carbonate and a radiochemical purity better than 99% (specific activity 57 mCi/mmole).
Synthesis of N,N‐[methyl‐14C]‐dimethylhydrazine of high specific activity
Authors: Cazer Frederick D. , Kausar Abdul R. , Kumar Kultar S. , Inbasekaran Muthiah N. , Witiak Donald T.
Published: October 2006

N,N‐[Methyl‐14C]‐Dimethylhydrazine hydrochloride () having a specific activity of 115 mCi/mmol, was synthesized in two steps. Dimethylation of acetophenone hydrazone with 14C‐methyl iodide (specific activity = 58 mCi/mmol) in the presence of potassium in liquid ammonia followed by acid catalyzed hydrolysis of the hydrazone afforded in a yield of 60.0% (>97% radiochemical purity).
2H‐labelled 3α‐hydroxy‐5α‐pregnane‐11,20‐dione and 3α,21‐dihydroxy‐5α‐pregnane‐11,20‐dione 21‐acetate
Authors: Vine J. , Treloar K.
Published: October 2006

3α‐Hydroxy‐5α‐pregnane‐11,20‐dione‐2,2,3,4,4‐2H5 of 78% isotopic purity was prepared from 3α‐hydroxy‐5α‐pregnane‐11,20‐dione. The major impurity (10%) was 3α‐hydroxy‐5α‐pregnane‐11,20‐dione‐2,2,4,4‐2H4. 3α,21‐Dihydroxy‐5α‐pregnane‐11,20‐dione‐2,2,3,4,4‐2H5 21‐acetate of 76% isotopic purity was prepared by reaction of the deuterated 3α‐hydroxy compound with lead tetraacetate. The major impurity (10%) was 3α,21‐dihydroxy‐5α‐pregnane‐11,20‐dione‐2,2,4,4‐2H4.
Markierung von Acetyl‐Ruthenocen mit 97Ru, 2H oder 3H
Authors: Schneider Michael , Wenzel Martin
Published: October 2006

Acetyl‐Ruthenocene was labelled by heating Acetyl‐Ferrocene with 97Rucl3. The tritium labelled compound was gained by exchange in tritium‐water at the acetyl side chain of acetyl‐ruthenocene. In a similar way acetyl‐ferrocene was labelled with deuterium.
A convenient synthesis of 2S, 3S‐[3‐2H]‐serine and 2S, 3R‐[2, 3‐2H2]‐serine
Authors: Slieker Lawrence , Benkovic Stephen J.
Published: October 2006

Both 2S, 3R‐[2, 3‐2H2]‐serine 5 and 2S, 3S‐[3‐2H]‐serine 6 have been prepared from (E)‐methyl‐[2, 3.‐2H2]‐acrylate and (Z)‐ethyl‐[3‐2H]‐acrylate, respectively. The acrylate esters were converted to a mixture of isomeric bromohydrins by treatment with N‐bromoacetamide. The ratio of 2‐bromo‐3‐hydroxy species to the 2‐hydroxy‐3‐bromo isomer was approximately 3:1. Conversion to the corresponding azido alcohols by treatment with NaN3 followed by catalytic reduction over Pd gave the alkyl esters of serine and isoserine. Purification and hydrolysis yielded serine in typically 20–25% yield from methyl or ethyl acrylate. Resolution was accomplished enzymatically by hog kidney acylase I treatment of the N‐acetyl derivative. Absolute configuration was determined by 1H NMR and the ratio of proton intensity in the diastereotopic positions at C–3 were measured to be HS/HR = 11 for 5 and HR/HS = 4.4 for 6.
Rapid tritium labelling of steroids using ethylaluminium chloride and boron tribromide catalysts
Authors: Brooks Ruth A. , Long Mervyn A. , Garnett John L.
Published: October 2006

A representative group of steroids have been labelled by exchange using ethylaluminium chloride and boron tribromide as catalyst and a trace of high specific activity tritiated water as isotope source. Careful choice of experimental conditions and a solvent inert to this exchange system ensures the production of high specific activity steroids with high radiochemical purity.
Syntheses with stable isotopes: D‐glucose‐6‐13C AND 1,6‐anhydro‐β‐L‐idopyranose‐6‐13C
Authors: Williams D. L. , Whaley T. W.
Published: October 2006

The synthesis of a mixture of D‐glucose‐6‐13C and 1,6‐anhydro‐β‐L‐idopyranose‐6‐13C and their resolution by column chromatography are described. The Kiliani reaction of hydrogen cyanide‐13C with 5‐aldo‐1, 2‐0‐isopropylidene‐D‐xylo‐pentofuranose afforded epimeric cyanohydrins. Rapid in situ hydrolysis of the nitriles was effected at 50°C to obtain a mixture of the corresponding alduronic acids. The latter were reduced with LiAlH4. Hydrolysis of the isopropylidene groups with trifluoroacetic acid gave a mixture of glucose and anhydroidose. After chromatographic separation, the labeled carbohydrates were obtained in yields of 48% and 25%, respectively. Results of a 13C NMR study of the Kiliani cyanohydrin reaction are also reported.
Synthesis of N,N′‐[methyl‐14C]‐dimethylhydrazine of high specific activity
Authors: Kumar Kultar S. , Cazer Frederick D. , Witiak Donald T.
Published: October 2006

N,N′‐[Methyl‐14C]‐dimethylhydrazine dihydrochloride (2) having a specific activity of 112.5 mCi/mmol was prepared in two steps from ethyl hydrazinedicarboxylate ( ) in dry THF and 14C‐methyl iodide with a specific activity of approximately 58 mCi/mmol. Methylation of following treatment with KOEt and subsequent hydrolysis of the intermediate ethyl N,N′‐[methyl‐14C]‐ dimethylhydrazinedicarboxylate () in conc. HC1 afforded in 64% yield following purification by thin layer chromatography.
Synthesis of pinacolyl [14C]methylphosphonochloridate
Authors: Horvat J. , Keglević D. , Klaić B. , Kveder S. , Ladešić B. , Ćosić M. , Zupanc S.
Published: October 2006

A three‐step synthetic route to pinacolyl [14C] methylphosphonochloridate () from [14C]methyl iodide is described Condensation of sodium di‐n‐butyl phosphite with [14C] methyl iodide gave di‐n‐butyl [14C] methylphosphonate () which was converted into [14C] methylphosphonic dichloride () by prolonged refluxing with thionyl chloride. Reaction of with pinacolyl alcohol in the presence of N,N‐di‐n‐propylaniline as the base afforded the title compound . The radiochemical yield of redistilled was 34.2% based on , and the overall radiochemical yield was 20.0% from [14C] methyl iodide.
The synthesis of 3‐methyl‐2‐[4‐14C]thiohydantoin a pharmacologically active metabolite of the antithyroid drug methimazole
Authors: Hood Hugh T. , Skellern Graham G.
Published: October 2006

Under basic conditions [14C]glycine reacts with methyl isothiocyanate producing 5‐methylthiohydantoic acid which cyclises at acidic pH to 3‐methyl‐2‐[4‐14C]thiohydantoin.
Direct preparation of 14C‐labeled 5‐allyl‐ and 5‐propyl‐2′‐deoxyuridine from [2‐ 14C]2′‐deoxyuridine
Authors: Ruth Jerry L. , White Steven K. , Bergstrom Donald E.
Published: October 2006

[2‐14C]5‐Allyl‐2′‐deoxyuridine was synthesized directly from [2‐14C]2′‐deoxyuridine using mercury, palladium, and 3‐chloropropene. [2‐14C]5‐Propyl‐2′‐deoxyuridine was obtained by hydrogenation of the [14C]5‐allyl‐2′‐deoxy‐uridine. Advantages of the synthetic method and its application to the preparation of other radiolabeled 5‐alkyl/alkeny1‐2′‐deoxyuridines are discussed.
Synthesis of deuterium‐labelled peptido‐aminobenzophenone [4‐chloro‐2‐(2′‐chlorobenzoyl)‐N‐(glycylglycyl)‐N‐methyl‐anilide] and its metabolites
Authors: Hashimoto Shin'Ichirō , Takahashi Shirō
Published: October 2006

Deuterium‐labelled peptido‐aminobenzophenone [4‐chloro‐2‐(2′‐chlorobenzoyl)‐N‐(glycylglycl)‐N‐methylanilide, 1] and its benzodiazepine‐metabolites were prepared for use as internal standards in the quantification of the peptido‐aminobenzophenone, chlorodiazepam, lormetazepam, chlorodesmethyldiazepam, and lorazepam at low levels in human plasma by selected ion monitoring.
Preparation of formyl‐deuterated benzaldehydes by direct photo‐deuteration or by photolysis of phenylglyoxylic acid
Authors: Defoin Albert , Defoin‐Straatmann Rosalie , Kuhn Hans Jochen
Published: October 2006

Two new photochemical methods are described to prepare D‐1‐benzaldehydes of high isotopic purity in good yield.
Preparation of some carpoxylic acids‐14C(U) from amino acids‐14C(U)
Authors: Ramamurthy T. V. , Viswanathan K. V. , Rao K. N.
Published: October 2006

A procedure for the facile preparation of labelled carboxylic acids from labelled α‐amino acids has been described. The reaction is attractive for the small scale synthesis of such compounds.
Synthesis of specifically 2H‐labeled reserpines, 3,4,5‐trimethoxybenzoic acids, and syringic acid
Authors: Roth Robert W. , Fischer Daniel L. , Pachta Janet M. , Althaus James F.
Published: October 2006

3,4,5‐Trimethoxy‐2H9‐, 4‐methoxy‐3,5‐dimethoxy‐2H6‐, and 4‐hydroxy‐3,5‐dimethoxy‐2H6‐benzoic acids were prepared from n‐propyl 3,4,5‐trihydroxybenzoate (n‐propyl gallate) by means of appropriate alkylation‐hydrolysis sequences employing iodomethane‐2H3 or dimethyl‐2H6‐sulfate as the deuterium source. 4‐Methoxy‐2H3‐3,5‐dimethoxybenzoic acid was similarly prepared from ethyl 4‐hydroxy‐3,5‐dimethoxybenzoate. The labeled trimethoxybenzoic acids were converted to the corresponding 2H‐labeled reserpines by condensation of the acid chlorides with methyl reserpate in pyridine according to the classical procedure. The labeled reserpine analog methyl 18‐O‐(4‐hydroxy‐3,5‐dimethoxy‐2H6)benzoyl reserpate was likewise prepared from 4‐hydroxy‐3,5‐dimethoxy‐2H6‐benzoic acid via the intermediate methyl 18‐O‐(4‐ethoxycarbonyloxy‐3,5‐dimethoxy‐2H6‐benzoyl)reserpate (syrosingopine‐2H6). The isotopic purity of each compound exceeded 99 atom percent 2H.
The preparation of 7‐chloro‐5‐(2‐chlorophenyl)‐1,3‐dihydro‐2H‐1,4‐benzodiazepin‐2‐one‐5‐14C
Authors: Kaegi H. H. , Burger W.
Published: October 2006

7‐Chloro‐5‐(2‐chlorophenyl)‐1,3‐dihydro‐2H‐1,4‐benzodiazepin‐2‐one labeled with carbon‐14 in carbon 5 of the diazepine ring has been synthesized. The compound was prepared in a multistep synthesis from barium carbonate‐14C in an overall yield of 23%.
Synthesis of 14C‐labelled latamoxef (6059‐S), a potent antibacterial
Authors: Komeno Taichiro , Nagasaki Tohru , Katsuyama Yoshihiko , Narisada Masayuki
Published: October 2006

Latamoxef (I) was labelled with 14C for metabolic and pharmacological studies.

The carbon‐14 label was introduced into the C‐1 position and the C‐2 position of the amido side chain to prepare (II) and (III) in overall yields of 10.6 and 13.5% based on barium carbonate‐14C, respectively.
The deuteration of acetanilides
Authors: Chin Siow K. , Collier Robin , Hutchinson David W.
Published: October 2006

The base‐catalysed exchange of a proton of the methyl groups in acetanilides can be used to incorporate deuterium into these amides. 4′‐Hydroxy‐2[2H]acetanilide (acetaminophen, paracetamol) can be prepared by the demethylation with boron tribromide of 4′‐methoxy‐2[2H]acetamide obtained by this base‐catalysed exchange.
Radiobromine labeled cholesterol analogs. Synthesis and tissue distribution of bromine‐82 labeled 6‐bromocholesterol
Authors: Bo‐Li Liu , Yu‐Tai Jin , Zhong‐Yun Pan , Maeda Minoru , Kojima Masaharu
Published: October 2006

Bromine‐82 labeled 6‐bromocholesterol (CL‐6‐Br‐82) was prepared by the reaction of 6‐chloromercurycholesterol with bromine‐82 labeled bromine in chloroform. Tissue distribution of CL‐6‐Br‐82 in rats was determined. The adrenal uptake of CL‐6‐Br‐82 reached a maximum of 136 %dose/g at 5 days after injection. The adrenal‐to‐liver ratio increased from 57 at 3 days to 141 at 5 days. The substitution of radiobromine for radioiodine in 6‐iodo‐cholesterol (CL‐6‐I) resulted in an agent which demonstrates less affinity for the adrenal gland than CL‐6‐I itself.
Synthesis of dimethyl‐[35S]sulphide
Authors: Spedding D. J. , Dyer D. L.
Published: October 2006

The synthesis of dimethyl‐[35S]sulphide in high yield from the contact of hydrogen‐[35S]sulphide and methanol over a γ Al2O3.1% SiO2 catalyst is described. The procedure produces high yields of dimethyl‐[35S] sulphide of low specific activity compared to that of the hydrogen‐ [35S]sulphide starting material.
3, 6‐dichloropicolinic acid‐2, 6‐ 14C
Authors: McKendry L. H.
Published: October 2006

A 20.4 mCi sample of 99% radiochemically pure 3,6‐dichloropicolinic acid‐2,6‐14C with a specific activity of 11.6 mCi/ mmole was synthesized via a five step process from glutarimide‐ 2, 6‐ 14C.
Stable isotope substituted spin labels. 2. An improved synthesis of perdeuterio‐15N‐(1‐oxyl‐2,2,6,6‐tetramethyl‐ 4‐piperidinyl)maleimide
Authors: Bates Barbara A. , Johnson Michael E. , Currie Bruce L.
Published: October 2006

Stable isotope substituted spin labels increase the resolution and sensitivity of EPR measurements. An improved synthesis of 15N‐(1‐oxyl‐2,2,6,6‐tetramethyl‐ 4‐piperidinyl)maleimide has been devised and utilized. This improved synthesis is accomplished in five steps instead of the normally required seven or more.
Synthesis of site specifically deuterated primaquines I. Quinoline ring deuterated primaquines
Authors: McChesney James D. , Sarangan Srinivasan
Published: October 2006

Site specific deuterated primaquines were prepared. The attempts to prepare these by deuterolysis of bromoprimaquines were unsuccessful because the required bromoprimaquines could not be produced satisfactorily by alkylation of the various bromo‐6‐ methoxy‐8‐aminoquinolines. Instead primaquines deuterated at positions 2, 3 and 4 were obtained by alkylation of site specifically deuterated 6‐methoxy‐8‐aminoquinoline. 5‐Deuteroprima‐ aquine was obtained by deuterolysis of the corresponding 5‐bromo compound and 7‐deuteroprimaquine was obtained by acid catalyzed exchange.
Preparation of radiolabeled pregnenolone analogs. 21‐Fluoro‐ pregnenolone‐21‐ 18F, 21‐fluoropregnenolone‐3‐acetate‐21‐ 18F, 21‐fluoropregnenolone‐7‐ 3H, and 21‐fluoropregnenolone‐3‐acetate‐7‐ 3H
Authors: Eng Robert R. , Spitznagle Larry A. , Trager William F.
Published: October 2006

21‐Fluoropregnenolone‐3‐acetate‐21‐1 8F (4b) and 21‐fluoropregnenolone‐21‐1 8F (8) were synthesized by nucleophilic substitution of the iodo group of the corresponding 21‐iodo analogs by F‐fluoride in an acetonitrile solution of 18‐Crown‐6. 21‐Fluoropregnenolone‐3‐acetate‐ 7‐ 3H (10b) and 21‐fluoropregnenolone‐7‐ 3H (9b) were synthesized by reacting 21‐ethoxalyl pregnenolone‐7‐ 3H (6b) with perchloryl fluoride.
11C‐Labeled ketanserin: A selective serotonin S2 antagonist
Authors: Berridge M. , Comar D. , Crouzel C. , Baron J‐C.
Published: October 2006

A selective serotonin S2 receptor antagonist, ketanserin, was prepared labeled with carbon‐11 by a rapid synthesis which uses no‐carrier‐added phosgene as the labeled precursor. The ring‐closure reaction in toluene of phosgene with the substituted 2‐aminobenzamide precursor gives a nearly quantitative yield of ketanserin. The 30 min procedure yields 150 mCi of HPLC purified ketanserin at a specific activity of 250 mCi/μ mol. The product's tissue distribution in mice shows a brain uptake and cerebrum to cerebellum ratio that encourages further in vivo receptor binding studies.
Synthese von im Cholinteil deuterierten 3‐sn‐ und 2‐Phosphatidylcholine
Authors: Laube Thomas , Kurreck Harry
Published: October 2006

Die Synthese des im Cholinteil deuterierten 3‐sn‐Phosphatidylcholins 15 und des isomeren 2‐Phosphatidylcholins 17 wird beschrieben. Ausgangsprodukte sind die entsprechenden Di‐O‐acylglycerine 8 bzw. 10, aus denen 15 bzw. 17 über die 1,3,2‐Dioxaphospholane in reiner Form aufgebaut werden. Die Bestimmung des Deuterierungsgrades durch kombinierte Auswertung von 1H‐ NMR‐Spektren und FD‐Massenspektren wird eingehend diskutiert.
Synthesis of dideuteromethylene hydrocarbons by copper catalyzed reaction of grignard reagents
Authors: Elliger Carl A.
Published: October 2006

The dilithium tetrachlorocuprate catalyzed reaction of Grignard reagents with long chain alkyl p‐toluenesulfonates provides specifically labelled dideuteromethylene hydrocarbons. The tosylate esters are readily obtained by LiAID4 treatment of fatty acid methyl esters followed by tosylation in pyridine.
One‐pot synthesis of 85 % enriched 13C(U)‐L‐asparagine from 13C(U)‐L‐aspartic acid
Authors: Lam‐Thanh Hung , Mermet‐Bouvier René , Fermandjian Serge , Fromageot Pierre
Published: October 2006

An improved high yield, racemization free synthesis of 85% 13C(U)‐L‐Asparagine by β‐ carboxamide formation on 13C(U) enriched L‐Aspartic acid is reported.
Synthesis of (±) [2‐14C]mevalonolactone in one step
Authors: Banerji Asoke , Kalena Govind P.
Published: October 2006

Condensation between 1‐trimethylsilyloxy‐3‐butanone and trimethylsilyl [2‐14C]acetate gave (±) [2‐14C]mevalonolactone in one step.
Synthesis of 2H, 13C, 15N‐isotomers of branched‐chain amino acids(1)
Authors: Kor Sun‐Shine Yuan
Published: October 2006

Synthetic schemes for 2(S,R)‐amino‐3‐[D3](R,S)methylpentanoic acid, 2(S,R)‐amino‐3‐[13C](R,S)methyl‐[4‐13C]pentanoic acid (isoleucine) and [1‐13C,15N](S)‐leucine are described. The side chain labeled isoleucines were constructed by first alkylating 2,4,4‐trimethyl‐2‐oxazoline with appropriate labeled alkyl halides and then reducing the resultant oxazolines to the aldehydes. Strecker synthesis yielded a mixture of isoleucine and alloisoleucine which was separated via the N‐acetyl derivatives. In a separate sequence, Strecker synthesis using 3‐methylbutanal, [13C]cyanide and [15N]ammonium hydroxide, followed by acid hydrolysis, gave [1‐13C, 15N]leucine amide. This amide was resolved by leucine aminopeptidase to produce [1‐13C,15N](S)‐leucine. Similar schemes were used for the synthesis of [1‐13C] or [15N](S)‐leucine and [1‐13C] or [15N](S)‐valine.
Synthesis of carbon‐14‐ and tritium‐labelled 4‐amino‐3‐ (4‐chlorophenyl) ‐butyric acid (baclofen)
Authors: Küng W. , Faigle J. W. , Kocher E. , Wirz B.
Published: October 2006

Two preparations of carbon‐14 labelled 4‐amino‐3‐(4‐chlorophenyl)‐butyric acid are described : First, the label is introduced in the 3‐position of the butyric acid chain in nine steps, starting from 14CO2. The total radiochemical yield is 30%, calculated from the first labelled intermediate, i.e. 4‐chlorobenzoic acid. Second, the 14C‐atom is incorporated in the 4‐position of the acid chain through three steps only, using K14CN as starting material with a yield of 39%.

Synthesis of the title compound labelled with tritium in the benzene nucleus is performed by catalytic bromine‐tritium exchange, affording a product with a specific radioactivity of 9.38 Ci/mmol. The des‐chloro compound which is obtained as a by‐product, is separated by column chromatography.
Preparation of 11‐cis‐retinal‐11‐3H
Authors: Kaegi H H. , Bupp J E
Published: October 2006

trans‐Retinal‐11‐3H was photolyzed by a fluorescent source to afford a mixture of isomeric retinals, from which 11‐cis‐retinal‐11‐3H was isolated by HPLC.
A simple method for the preparation of carrier free I‐labelled 4‐iodoantipyrine
Authors: Diksic Mirko , Kodery Balachandran
Published: October 2006

A simple new method for synthesis of a carrier free(131I)‐4‐iodoantipyrine has been developed. The procedure uses dry column chromatography on silica gel, where reaction between iodine‐131 and antipyrine is carried out simultaneously with elution of (131I)‐4‐iodoantipyrine. The labelling yield is around 80 per cent; radiochemical purity of the final product exceeds 98 per cent.
A simple chemical method of labeling hematoporphyrin derivative with technetium‐99m
Authors: Wong Dennis W.
Published: October 2006

Hematoporphyrin derivative(HPD), a fluorescent compound known to be selectively accumulated in neoplasms, is labeled with 99mTc by a chemical method. Radiochemical analyses indicated that the labeled product contains an average of 91% 99mTc‐HPD, 6% unbound 99mTc‐(Sn)complex species and less than 3% free 99mTc. Data from acid precipitation analysis demonstrate the presence of two radiolabeled HPD fractions; an insoluble black precipitate and an acid soluble fraction with an average of 66% and 25% respectively. The labeling mechanism is not known. Presumably, labeling of HPD involves the formation of a coordinated complex with reduced 99mTc forming a radioactive metalloporphyrin compound. 99mTC‐HPD, like the parent compound, exhibits strong fluorescence when exposed to an appropriate ultra violet light source.
Synthesis of [2‐3H] creatine
Authors: Daly Marie M. , Lalezari I.
Published: October 2006

A method for preparing [2‐3H] creatine with high specific activity is described. [2‐3H] Sarcosine is prepared from [2‐3H] glycine and purified by ion‐exchange chromatography. [2‐3H] Creatine is then synthesized by reaction of the labeled sarcosine with cyanamide, and isolated by ion‐exchange chromatography. Radiochemical purity of the labeled creatine was verified by isotope dilution analysis and by thin‐layer chromatography.
The synthesis of tritium‐labeled misonidazole
Authors: Born Jerry L. , Smith Brian R.
Published: October 2006

The3 synthesis of tritium‐labelled misonidazole via the NaB H4 reduction of 1‐(3‐methoxy‐2‐oxopropyl)‐2‐nitro‐1H‐imidazole is described. Purification of labeled misonidazole was accomplished by recrystallization. The purity of the labeled compound was verified by HPLC.
Synthesis of 2‐(2,4‐difluorophenyl)‐4,5‐BI‐(4‐methoxyphenyl) [2‐14C] imidazole
Authors: Scott P. W. , Hawkins D. R.
Published: October 2006

The synthesis of 2‐(2,4‐difluorophenyl)‐4,5‐bis(4‐methoxyphenyl)imidazole labelled with carbon‐14 in the 2‐position of the imidazole ring has been achieved in four stages starting from barium [14C] carbonate via 2,4‐difluoro‐[carboxyl]14C benzoic acid and the corresponding aldehyde. The overall radiochemical yield was 20% and the product obtained with a radiochemical purity in excess of 99% by the analytical systems used.
Tritiated guanethidine of high specific activity
Authors: Wyrick Steven D. , Pittman A. Wayne , Loeffler Larry J.
Published: October 2006

Due to the desire for biological assay techniques of greater sensitivity and specificity than presently exist for the antihypertensive drug guanethidine, tritium labeled guanethidine of high specific activity was prepared for use in radioimmunoassay procedures. This drug has been labeled in other positions than described here resulting in much lower specific activity and less than optimal sensitivity in RIA work. The work described here involves the preparation, deuteration and tritiation of an olefinic precursor, N‐(2‐aminoethyl)‐Δ4‐hexahydroazocine which was converted in one subsequent step to tritiated guanethidine with a specific activity of 72 Ci/mmole (145 mCi/mg) for the sulfate salt and 36 Ci/mmole (182 mCi/mg) for the free base.
A synthetic scheme for the preparation of oxygen labelled furan compounds
Authors: Jennings Paul W. , Gingerich Samuel B.
Published: October 2006

Four alicyclic furan compounds have been synthesized with incorporation of 18O in the furan oxygen. Basically, a stable ketonic intermediate of the synthetic scheme was exchanged with H218O in THF with a catalytic amount of HCl.
Synthesis of (3RS)‐[2,3‐3H2 (N)]‐β‐leucine
Authors: Aberhart D. John , Lin Horng‐Jau
Published: October 2006

(3RS)‐[2,3‐3H2(N)]‐β‐Leucine, a substrate for assay of leucine 2,3‐amino‐mutase, has been synthesized. Ethyl (Z)‐3‐acetamido‐4‐methylpent‐2‐enoate was reduced with 3H2 gas over Pd(C) to (3RS)‐[2,3‐3H2(N)]‐β‐leucine ethyl ester, which was hydrolyzed with HCl‐H2O to (3RS)‐[2,3‐3H2(N)]‐β‐leucine. The crude product was purified, on a small scale by preparative HPLC. Analysis of the crude product by 3H NMR, and of the purified product by equilibration analysis indicated a tritium distribution of ca 70% at C‐3 and 30% at C‐2.
Synthesis of CD3‐labelled 3‐methoxytyramine, normetanephrine and metanephrine for use as internal standards in mass fragmentographic analyses
Authors: Muskiet Frits A. J. , Pavel Stanislav , Stob Gerrie J. , Elzinga Henk
Published: October 2006

The preparation of CD3‐labelled 3‐methoxytyramine, normetanephrine and metanephrine from their parent catecholamines is described. The syntheses include N‐maleylation, O‐methylation by dimethylsulfate‐D6, removal of the protecting group by acid hydrolysis and partial purification of the reaction product. Examples of the use of the deuterium labelled O‐methylated catecholamine metabolites as internal standards for the ammonia chemical ionisation mass fragmentographic determination of their naturally occurring analogs in urine, are given.
Synthesis of diethyl 4‐(benzothiazol‐[2‐14C]‐2‐yl) benzylphosphonate ([14C]KB‐944)
Authors: Awata Norio , Sato Akeshi
Published: October 2006

Diethyl 4‐(benzothiazol‐[2‐14C]‐2‐yl)benzylphosphonate ([14C]KB‐944), a new calcium antagonist, was prepared from labelled carbon dioxide.

The synthetic intermediate, [14C]p‐toluic acid, obtained by the Grignard reaction was condensed with 2‐aminothiophenol, brominated with N‐bromosuccinimide, and followed by the Arbuzov reaction.

[14C]KB‐944, having the specific activity 52.7 mCi/mmol, was obtained in 36% overall yield from [14C] barium carbonate and its radiochemical purity was 99.3% in reverse isotope dilution analysis.
The biosynthesis of three macrocyclic pyrrolizidine alkaloids retrorsine, seneciphylline and senecionine using senecio vulgaris
Authors: Segall H. J. , Brown C. H. , Paige D. F.
Published: October 2006

Senecio vulgaris, a plant containing 3 macrocyclic pyrrolizidine alkaloids (PAs) was grown under atmospheric CO2, 14CO2, and 13CO2 conditions. This report describes the plant growth chamber, the growing conditions the plants were subjected to and the amounts of macrocyclic PAs isolated from the plants. In addition, a number of radiolabelled experiments are described including a single 25 mCi pulse 14CO2 experiment, a dual 13,·14CO2 experiment and an 800 mCi Pyrrolizidine Alkalolids 14CO2 experiment. The 14C labelled macrocyclic PAs isolated from these experiments (retrorsine, seneciphylline and senecionine) are presently being used in various metabolism studies.
Application of spin labeling to drug assays. III. [15N, 2H13]2,2,5,5‐tetramethylpyrroline‐1‐oxyl‐3‐carboxylic acid coupled to phenytoin
Authors: Yost Yul , Polnaszek Carl F. , Holtzman Jordan L.
Published: October 2006

Phorone and [2H14]phorone were cyclized with 15NH3 or 15N2H3 to [15N]‐ or [15N, 2H17]‐4‐oxo‐2,2,6,6‐tetramethylpiperidine which were then brominated at C‐3 and C‐5. Ring contraction then gave 2,2,5,5‐tetramethylpyrroline‐3‐carboxamide, which with H2O2 gave the corresponding nitroxide. Hydrolysis in base of the doubly labeled nitroxide then gave [15N, 2H]2,2,5,5‐tetramethylpyrroline‐1‐oxyl‐3‐carboxylic acid. The latter, when coupled to phenytoin, afforded a spin‐labeled drug of high sensitivity for detection by ESR technique. If the synthesis was started with [2H14]phorone, negligible loss of deuterium was noted in the final product even when protiated reagents were used.
The synthesis of 14C, 3H and 2H labeled 7‐ethoxycoumarins
Authors: Walsh John S. , Mertel Holly E. , Miwa Gerald T.
Published: October 2006

7‐Ethoxycoumarins labeled in the ethoxy side chain were prepared from 7‐hydroxycoumarin and the correspondingly labeled ethyl iodide or ethyl tosylate. Persulfate oxidation of 7‐[1,1‐2H2]ethoxycoumarin gave 7‐[1,1‐2H2]ethoxy‐6‐hydroxycoumarin. 7‐[1,1‐2H2]‐Ethoxy[6‐2H]coumarin was prepared from 7‐hydroxy[6‐2H]coumarin, obtained via NaB2H4/PdCl2 reduction of 6‐chloro‐7‐hydroxycoumarin.
Synthesis of 13C and 14C labeled pirmenol hydrochloride
Authors: Hicks James L. , Huang C. C.
Published: October 2006

Pirmenol hydrochloride (cis‐(±)‐α‐[3‐(2,6‐dimethyl‐1‐piperidinyl)‐propyl]‐α‐phenyl‐2‐pyridinemethanol monohydrochloride, CI‐845), a new anti‐arrhythmic drug, was labeled with 13C and 14C. Labeled benzoyl chloride reacted with 2‐trimethylsilylpyridine to yield 2‐benzoylpyridine. Treatment of the latter with cis‐1‐(3‐chloropropyl)‐2,6‐dimethylpiperidine gave pirmenol free base, which was subsequently converted to the HCl salt.
A simple synthesis of (RS)‐[2‐2H] glycine by the reductive amination of glyoxylic acid
Authors: White R. H.
Published: October 2006

The synthesis of (RS)‐[2‐2H] glycine by the reduction of a dilute solution of glyoxylic acid in aqueous ammonia by sodium borodeuteride is described. A reaction condition is presented under which the principal side product of the reduction, iminodiacetic acid, is minimized.
Mikropräparation ringdeuterierter prostaglandine
Authors: Meese Claus O.
Published: October 2006

Starting from prostaglandin E2 ring‐labelled 2H4‐prostaglandins (PGF2α, PGF2ß, 6‐keto‐PGF1α and PGl2 sodium salt as intermediate) were prepared in their natural configuration. The carbon‐13 NMR spectra of 2H4‐PGF2αß methyl ester, which allow the localization of the labelled positions, are presented. The utility of these ring‐labelled prostaglandins as internal standards for GC/MS analysis of biological samples and as substrates for the preparation of other labelled prostaglandin metabolites is briefly discussed.
Tritium NMR spectroscopy of steroids
Authors: Funke Carel W. , Kasperen Frans M. , Wallaart Jan , Wagenaars Gerard N.
Published: October 2006

The 3H NMR spectra of a series of 7 steroids tritiated at C(1), C(2), C(6), C(7), C(9) and C(16) yield quantitative information on the 3H distribution in these compounds. Deuterated chloroform is not a good solvent to examine the regio‐ and stereospecificity of the labelling process for acid labile positions such as C(2) in a 3‐oxosteroid and C(6) in a 3‐oxo‐Δ4‐steroid.
Tritiated peptides. Part 141. Catalytic exchange labelling of various synthetic peptides
Authors: Brundish Derek E. , Combe M. Grace , Wade Roy
Published: October 2006

Several synthetic protected peptides have been catalytically exchangelabelled using tritium gas to a level between 0.1 and 12.5 Ci mmol−1. High specific activities could be achieved for histidine‐containing peptides, and the factors influencing this have been investigated as have the location and stability of the introduced label. L‐Cysteinecontaining peptides gave rise to the corresponding peptides containing L‐alanine heavily labelled with tritium. The substitution pattern within the alanine residue has been established.
Synthese et marouage du tetramethyl‐cyclen
Authors: Pilichowski Jean‐François , Borel Michèle , Michelot Josette
Published: October 2006

On décrit la synthèse d'un nouveau produit représentatis de la classe des polyamines macrocycliques. Le Tétraméthyl‐[14C]‐cyclen obtenu par la méthode d'Eschweiler et Clarke est purifié par l'intermédiaire de son complexe au cuivre.
Incorporation of radiocarbon into organic compounds
Authors: Peng C. T.
Published: October 2006

A single pass of a ternary gas mixture containing 14CO2, H2 and hydrocarbon (methane, ethylene, or acetylene) through a microwave‐induced plasma can give rise to labeled propene, cyclopropane (or propane), C4Hn, C5Hn, benzene and toluene. By varying the plasma conditions and the composition of the feed gas, formation of the labeled product(s) can be selective. The technique has potential use in rapid synthesis of 11C‐labeled compounds.
Synthesis of deuterated 3‐methylcyclohexanones
Authors: Kallmerten James
Published: October 2006

The efficient, regiospecific preparation of the series of deuterated 3‐methylcyclohexanones is described.
Synthesis of 14C‐labelled 1‐methanesulphonyl‐3‐(1‐methyl‐5‐nitro‐1H‐imidazol‐2‐YL)‐2‐imidazolidinone, (Go 10213)
Authors: Anjaneyulu B. , Maller R. K. , Nagarajan K.
Published: October 2006

For pharmacokinetic and metabolism studies in animals and humans, Go 10213 was labelled with carbon‐14 at the 2‐position of the 5‐nitroimidazole ring system, in an overall yield of 22% starting with potassium[14C]‐thiocyanate. The labelled compound had a specific activity of 4.65 μCi/mg or 1.34 mCi/mmol.
Synthèse de l'Oxetorone (14C‐6) : (diméthylamino‐3 propylidène‐1)‐6 benzofuro [2,3‐e] 12H‐benzo [b] oxépine (14C‐6). Séparation chromatographique des isomères (E) et (Z)
Authors: Noel J. P. , Pichat L. , Benakis A.
Published: October 2006

Synthesis and chromatographic separation of (E) and (Z) isomers of [6‐14C] oxetorone : [6‐14C] 6‐(3‐Dimethylaminopropylidene)[2, 3‐e] benzofuro‐12H‐benzo [b] oxepin*, hydrogen fumarate. A new synthesis of [6‐14C] oxetorone was devised allowing the three step preparation from 14CO2 of this drug used in the treatment of migraine. 2‐bromo‐3‐phenoxymethyl benzo [b] furan : 10 was prepared from 3‐methyl [b] furan 7. In diethyl ether 10 gave with n‐butyllithium the corresponding : 2‐lithio 3‐phenoxymethyl benzo [b] furan the carbonation of which with 14CO2 gave [2‐carboxy 14C] 3‐phenoxymethyl benzo [b] furan in a 70% yield based on 14CO2. The carboxylic acid 5 was transformed into the corresponding acyl halide which was ring closed into [6‐14C] oxepinone 6. Condensation of the latter with 3‐dimethylaminopropyl magnesium chloride followed by dehydration under hydrochloric acid treatment and isolation as fumarate gave [6‐14C] oxetorone with an overall yield of 24% based on 14CO2. The (E) and (Z) isomers of oxetorone were separated by reverse phase HPLC.
A total synthesis of [9′, 10′‐3H]‐labelled paf‐acether
Authors: Wichrowski Boguslaw , Michel Elie , Heymans Françoise , Roy Jean , Morgat Jean‐Louis , Godfroid Jean‐Jacques
Published: October 2006

1‐O‐octadecen‐[9′, 10′]‐yl 2‐o‐benzyl sn‐glycero‐3‐phosrylcholine was obtained from 1‐O‐octadecen‐[9′, 10′]‐yl sn‐glycerol by tritylation, benzylation and phosphorylation with 2‐bromoethyl phosphoryl dichloride followed with trimethylamine reaction. Catalytic tritiation of the double bond led to labelled “lyso” PAF‐acether from which PAF‐acether with a specific radioactivity between 40 and 50 Ci/mmole was obtained by acetylation.
A new approach to the synthesis of 14C labelled DL‐malic acid
Authors: Ramamurthy T. V. , Viswanathan K. V.
Published: October 2006

The 2‐carbon units, glycine and glyoxylate are combined by a mild reaction via the copper chelate of glycine. The resulting β‐hydroxy aspartic acid is converted to DL‐malic acid by means of hydroxylamine 0‐sulfonic acid. The overall yields are in the range of 35–50% in submillimolar preparations.
The synthesis of [14C]‐L‐lysyl‐N‐(2‐benzoyl‐4‐chlorophenyl)‐N‐methyl glycinamide
Authors: Harrison J. M.
Published: October 2006

A procedure has been developed for the synthesis of L‐lysyl‐N‐(2‐benzoyl‐4‐chlorophenyl)‐N‐methyl glycinamide labelled with carbon‐14. The label was introduced using [14C]carbon dioxide to prepare the intermediate [carboxyl‐14C]benzoic acid.
Synthesis and biodistribution of radioiodinated‐5‐iodonicotine
Authors: Chan S. M. , Basmadjian G. P. , Marten D. F. , Sadek S. A. , Magarian R. A. , Grunder J. R. , Ice R. D.
Published: October 2006

5‐Bromonicotine, synthesized from nicotinic acid, was autoclaved with Na125I in the presence of copper sulfate and glacial acetic acid to give 5‐[125I]iodonicotine. The radiochemical yield was 25.3%. The specific activity of the product was approximately 61 mCi/mmole. Biodistribution studies of 5‐[125I]iodonicotine, performed in rats, showed that the labelled compound accummulated rapidly in the brain and the adrenal gland. The highest uptake of radioactivity in these organs occurred at 5 minutes after administration. The brain‐to‐blood and the adrenal‐to‐blood ratios at this time interval were 2.6:1 and 3.3:1 respectively.
Silica gel‐assisted reduction of nitrostyrenes to 2‐aryl‐2‐[2H]‐1‐nitroethanes with sodium borodeuteride
Authors: Sinhababu Achintya K. , Borchardt Ronald T.
Published: October 2006

Reduction of nitrostyrenes with sodium borodeuteride in the presence of silica gel (70‐270 mesh) in a mixture of chloroform and 2‐propanol gave the corresponding deuterated nitroethanes in near quantitative yields, free of dimeric products with 72‐81% deuterium incorporation. The method was applied to the synthesis of 2‐phenyl‐, 2‐[4‐methoxyphenyl]‐, 2‐[3,4‐dimethoxyphenyl]‐, 2‐[3,4,5‐trimethoxyphenyl]‐, and 2‐[2,4,5‐trimethoxyphenyl]‐2‐[2H]‐l‐nitroethanes.
Self‐decomposition of DL‐/methyl‐14C/carnitine to labelled β‐methylcholine and acetonyltrimethylammonium
Authors: Löster Heinz , Seim Hermann , Strack Erich
Published: October 2006

The self‐decomposition rate of DL‐/methyl‐14C/carnitine (32 mCi/mmol) in the crystalline betaine form was studied. It was found to be decomposed to 39.5 % in 4.5 years. On this basis a self‐decomposition coefficient G = 4.2 was calculated for the solid state. DL‐/N‐methyl‐14C/β‐methylcholine was the most important labelled product of decomposition (12%). /N‐methyl‐14C/acetonyl‐trimethylammonium was also present among the radiolytic products (2%). It was detected as its 2,4‐dinitrophenylhydrazone by means of thin‐layer chromatographic separation and autoradiography.
Preparation of 2,2,2(2H3)‐diazoethane
Authors: Meese Claus O.
Published: October 2006

2,2,2(2H3) Ethyl‐N‐nitroso‐p‐toluenesulfonamide 6a, prepared in three steps from trideuteroacetonitrile 2a (overall yield 71%), has been subjected to alkaline decomposition to give after co‐distillation with ether/n‐hexane solutions of 2,2,2(2H3)‐diazoethane 1a. As shown by quantitative studies and from NMR and mass spectra, respectively, carboxylic acids were completely converted by 1a under mild reaction conditions into highly labelled (>96% d3, (<0.3% d0) 2,2,2(2H3)‐ethyl esters. The ready preparation of 1(2H1,2)‐ethyl 4‐nitrobenzoate 15 from 9 and unlabelled 1b under H/D exchange conditions illustrates the possibility of further introduction of 2H or 3H into an ethyl group. The molar extinction coefficient of 1a, b has been determined (ϵ (470 nm)=8.4).
[103RU]‐markierte ruthenocen‐der ivate biogener amine
Authors: Wenzel M. , Asindraza P. , Schachschneider G.
Published: October 2006

The ruthenocene derivatives of different biogenic amines labelled with 103RU in the ruthenocene moity were synthesized. In a first step the central atom of ferrocene was exchanged with 103RuCl3 yielding [103RU]‐ruthenocene, by vilsmeier‐formylation the radioactive ruthenocene aldehyde was synthesized which was condensed with the desired amine to the Schiff'sche base, followed by the reduction of the CN double bond by NaBH4.
The aryl group controls the α/γ regioselectivity in deuterations of 2‐(p‐substituted benzyl)‐4,6‐dimethylpyrylium salts (1)
Authors: Balaban Alexandru T. , Gheorghiu Mircea D. , Balaban Teodor Silviu
Published: October 2006

A kinetic study is reported for the deuteration (in sodium formate‐con‐taning HCOOD at 50–73°) of 2‐benzyl‐4,6‐dimethylpyrylium perchlorate and of its derivatives possessing para‐substituents at the phenyl ring (NO2, Cl, Me, OMe). Intramolecular comparison of deuteration rates indicates that the 4‐methyl is always deuterated 8–10 times faster than the 6‐methyl; however, the 2‐methylene group is deuterated with a rate dictated by the nature of the aryl group : faster than the 4‐methyl with p‐NO2 and p‐C1 substituents, more slowly than the γ‐methyl group with p‐Me and p‐OMe substituents. Hammett plots show good correlations for relative deuteration rates of the methylene group, and for 1H‐NMR chemical shifts for methyl and methylene protons.
The preparation of carbon‐14 labelled 1‐[4‐(2‐diethylamino‐ethoxy) phenyl]‐1, 2‐diphenyl‐2‐chloroethene (clomiphene) and 1‐[4‐(2‐(N‐pyrrolidinyl) ethoxy) phenyl]‐2‐(4‐methoxyphenyl)‐2‐nitro‐2‐phenylethene (CI‐628, nitromiphene)
Authors: Ruenitz Peter C. , Bagley Jerome R.
Published: October 2006

The preparation of [14C] clomiphene and [14C] nitromiphene from [methylene‐14C] benzyl chloride is described. The overall radio‐chemical yield and specific activity of the former are 53% and 0.53 mCi/mmol and those of the latter are 26% and 0.23 mCi/mmol. The method described is of micromolar scale designed for maintaining cost economy while yielding final products of sufficient radioactivity for in vitro and in vivo metabolism studies.
13C labeled benzo[a]pyrenes and derivatives 3. Benzo[a]pyrene‐4,5‐oxide‐4‐13C and benzo[a]pyrene‐4,5‐oxide‐5‐13C
Authors: Hylarides Mark D. , Daub Guido H. , Vanderjagt David L. , Silverman I. Robert
Published: October 2006

The synthesis of benzo[a]pyrene‐4,5‐oxide‐4‐13C and benzo[a]‐pyrene‐4,5‐oxide‐5‐13C from the corresponding 13C labeled 4,5‐dihydrobenzo[a]‐pyrene‐4,5‐diones is described. Reduction of the quinone with potassium borohydride in freshly distilled peroxide‐free 2‐propanol gave the trans‐diol which was directly cyclized to the oxide by refluxing with DMF‐DMA in chloroform/OMF. The overall yield of the oxide was 48–53% for the two steps. The requisite quinones were available in five steps from 1,2‐dihydrochrysen‐4(3H)‐one as described in an earlier paper. Overall yield of the oxide from the chrysenone was 27%. 13C NMR of the labeled oxides in CDCl3 gave chemical shifts of 56.80 for C5 and 56.20 for C4 (δC from TMS) of benzo[a]pyrene‐4,5‐oxide.
Tritium labelling of benzamide drugs
Authors: Pri‐Bar Ilan , Buchman Ouri
Published: October 2006

Methods for tritiation of sulpiride, sultopride and metoclopramide were developed and optimized. 3H‐sulpiride (7.1 Ci/mmol), 3H‐sultopride (2.1 Ci/mmol) and 3H‐metoclopramide (18.0 Ci/mmol) were obtained by hydrodebromination of the related bromo derivatives. The bromo derivatives were prepared, in turn, by appropriate procedures specified for each case.