bluuebunny/crossref_metadata_2025_split huggingface dataset:
Radiolabelling by tritium and [125I]iodine of an angiotensin II related Peptide
Authors: Pham P. , Ramombordes C. , Perret C. , Ronco P. , Budisavljevic M. , Verroust P. , Beaucourt J. P. 
Published: October 2006

AbstractWe describe the 3H‐ and 125I‐ labelling of Glu‐Gly‐Val‐Tyr‐Val‐His‐Pro‐Val, (hIIA), an octapeptide encoded by an RNA strand complementary to the human angiotensin II (AII) mRNA.The labelling of this peptide with 125I was performed by two ways : 1/ Mono‐iodination of the Tyr residue, using Na125I in the presence of Chloramine T; 2/ Coupling of the [125I]Bolton‐Hunter reagent to the terminal amine group of the octapeptide.The synthesis of the tritiated (3,5‐3H2‐Tyr4)octapeptide was achieved by a two step synthesis : di‐iodination of the peptide followed by its catalytic dehalogenation in the presence of tritium gas.The compounds obtained inhibited the binding of AII to its receptors or antibodies but showed no direct binding to these proteins, suggesting no competition between AII and hIIA for these protein binding sites.
The synthesis of the carbonyl‐14C analog of zatosetron maleate, a potent, long‐acting, orally effective 5‐HT3 receptor antagonist
Authors: O'Bannon Douglas D. , Wheeler William J. 
Published: October 2006

AbstractEndo‐5‐chloro‐2,3‐dihydro‐2,2‐dimethyl‐N‐(8‐methyl‐8 ‐azabicyclo‐[3.2.1.]‐oct‐3‐yl‐7‐benzofurancarboxamide‐[carbonyl‐14C] (Z)‐2‐butenedioate (zatosetron‐[14C] maleate, 1), has been prepared from 5‐chloro‐7‐bromo‐2,3‐dihydro‐2,2‐dimethylbenzofuran (5) in four radiochemical steps with the reaction of 5 with K14CN/CuCN as the key step. The synthesis of 5 from 2‐bromo‐4‐chlorophenol is also outlined.
Synthesis of carbon‐14 labelled cis‐2‐amino‐1,9‐dihydro‐9‐[4‐(hydroxy‐methyl)‐2‐cyclopenten‐1‐YL]‐6H‐purine‐6‐one; [8‐14C]carbovir: A promising anti‐aids drug
Authors: Gopinathan M. B. , Kepler J. A. 
Published: October 2006

AbstractThe synthesis of the title compound (3) is described. Treatment of a solution of triethyl [14C]orthoformate in dry chloroform with cis‐[4‐(2,5‐diamino‐6‐chloro‐4‐pyrimidinyl)‐amino]‐2‐cyclopentenyl carbinol (1) afforded crude 2. Hydrolysis of crude 2 with 2 N sodium hydroxide gave 3 in 34% overall radiochemical yield with specific activity of 19.6 mCi/mmol.
Synthesis of [14CO]ellagic acid
Authors: Zeng Wenguang , Heur Young‐Hun , Kinstle Thomas H. , Stoner Gary D. 
Published: October 2006

Abstract[14CO]Ellagic acid with a chemical purity of 98.9% and radiochemical purity of 99.9% was synthesized with an overall yield of 16% (both chemically and radiochemically). Reaction of 14CO2 with lithiated 3,4,5‐trimethoxybenzene and demethylation of the resulting 3,4,5‐trimethoxybenzoic acid was followed by esterification and coupling of methyl gallate into ellagic acid. Two efficient coupling methods were employed: direct aeration and aeration of methyl gallate in the presence of the phenolic oxidase, tyrosinase. The latter method produced the highest yield and purity. This preparation produced [14CO]ellagic acid with a specific activity of 20 mCi/mmol. The yields of labeled 3,4,5‐trimethoxybenzoic acid and ellagic acid based on Ba14CO3 were 65% and 16%, respectively.
Asymmetric synthesis of (2S)‐and (2R)‐4‐(3‐t‐butylamino‐2‐hydroxypropoxy)‐benzimidazol‐2‐[11C]‐one ((S)‐and (R)‐[11C]‐CGP 12177) from optically active precursors
Authors: Hammadi Akli , Crouzel Christian 
Published: October 2006

AbstractEnantiomers of CGP 12177 ((2S)‐and (2R)‐4‐(3‐t‐butylamino‐2‐hydroxypropoxy)‐benzimidazol‐2‐one), a potent adrenergic β‐receptor antagonist were synthesized and labelled with 11C for Positron Emission Tomography studies of β‐receptors in heart. The synthesis was accomplished from (2S)‐and (2R)‐3‐tosyloxy‐1,2‐propanediol acetonide. Enantiomeric excess was greather than 95% for each of the prepared enantiomers. (S)‐ and (R)‐[11C]‐CGP 12177 were obtained with a specific radioactivity of 29.6‐44.4 GBq/μmol.
Synthesis of 2H‐, 3H‐ and 14C‐labelled CP‐45,634 (sorbinil)
Authors: Howard Harry R. , Evans Michael , Sarges Reinhard 
Published: October 2006

AbstractThe syntheses of 3H‐ and 14C‐label led S‐(+)‐6‐fluoro‐2,3‐dihydrospiro‐[4H‐1‐benzopyran‐4,4′‐imidazolidin]‐2′,5′‐dione (sorbinil, CP‐45,634), an aldose reductase inhibitor with potential utility in the treatment of chronic diabetic complications, are described. Tritiated sorbinil was prepared by a reductive dehalogenation of the 8‐chloro substituted analog with 3H2. 14C‐labelled CP‐45,634 was prepared using a Bucherer‐Bergs synthesis of the racemic hydanto in beginning with 2,3‐dihydro‐6‐fluoro‐4H‐1‐benzopyran‐4‐one and 14C‐potassium cyanide, followed by brucine resolution to isolate the pharmacologically active S‐(+)‐enantiomer.
Synthesis of [1,1′ ‐13C2]‐L‐cystine
Authors: Uchida Kenichi , Kainosho Masatsune 
Published: October 2006

AbstractAn improved synthesis of [1,1′‐13C2]‐L‐cystine which includes the optical resolution of the labeled N‐acetyl‐S‐benzyl‐DL‐cysteine by Aspergillus acylase into S‐benzyl‐L‐cysteine is described.
Synthesis of 14 (R,S)‐[18F]fluoro‐6‐thia‐heptadecanoic acid (FTHA)
Authors: Degrado Timothy R. 
Published: October 2006

AbstractNo‐carrier‐added (n.c.a) 14(R,S)‐[18F]fluoro‐6‐thia‐heptadecanoic acid (FTHA) has been synthesized for evaluation as a PET tracer for myocardial long chain fatty acid utilization. The n.c.a. nucleophilic radiofluorination of benzyl 14(R,S)‐tosyloxy‐6‐thia‐heptadecanoate in acetonitrile utilized (cryptate 2.2.2/K)2CO3 for anion activation. The resulting [18F]fluoro‐ester was quantitatively hydrolyzed with addition of aqueous KOH and the product purified by reversed phase HPLC. The radiochemical yield of purified FTHA was 35–65% (n=5) with a synthesis time of 50 min. Radiochemical purity was >99%.
Synthesis of 14‐[2H]arteether, an experimental antmalarial drug
Authors: Hu Yulin , Ziffer Herman 
Published: October 2006

AbstractA reaction sequence employing a fungus mediated oxidation of arteether, an experimental antimalarial drug, was used to introduce a hydroxyl group on C‐14. The hydroxyl group was replaced by a deuterium by preparing the tosylate and reductively cleaving it with sodium borodeuteride in DMSO. A reaction sequence to introduce a second label was also demonstrated it involved oxidation of the alcohol, with catalytic quantities of tetra‐n‐propylammonium perruthenate, followed by reduction with sodium borodeuteride to regenerate the alcohol. Use of both reactions sequences yield arteether containing two deuterium.
Radioiodination of 7‐methoxy‐ and 6,7‐dimethoxy‐4‐bromomethylcoumarins
Authors: Baranowska‐Kortylewicz Janina , Kortylewicz Zbigniew P. 
Published: October 2006

AbstractTwo coumarins, 4‐bromomethyl‐6,7‐dimethoxy‐2‐oxo‐2H‐benzopyran (1) and 4‐bromomethyl‐7‐methoxy‐2‐oxo‐2H‐benzopyran (3), were radioiodinated using trifluoroacetyl hypoiodite. The dimethoxy derivative 1 gave only a single regioisomer 3‐[125I]iodo‐4‐bromo‐methyl‐6,7‐dimethoxy‐2‐oxo‐2H‐benzopyran (2). The average yield for no‐carrier‐added preparations of 2 was 30%. 125/127I‐2 and 127I‐2 were produced in over 50% yield. In no‐carrier‐added syntheses 7‐methoxy‐coumarin 3 gave 3‐[125I]iodo‐4‐bromomethyl‐7‐methoxy‐2‐oxo‐2H‐benzopyran(5) as the major product (30%) accompanied by a small amount (3–7%) of the 6‐[125I]iodo‐analog 4. When an equimolar amount of iodide was used (i.e. carrier‐added syntheses) 4 and 5 were produced in over 20% yield each. Under these conditions the 8‐iodo‐regioisomer was not formed from either 1 or 3 possibly as the result of steric effects. Sonication greatly accelerated rates of radioiodination reducing the time required to achieve quantitative substitution of 127I from about 4 h to 20 min.
Stereoselective Synthesis of Stable Isotope Labeled L‐α‐Amino Acids: Synthesis of L−[4−13C] and L−[3,4−13C2]Aspartic Acid
Authors: Lodwig Siegfried N. , Unkefer Clifford J. 
Published: October 2006

AbstractWe have developed a stereoselective route to isotopically labeled L‐aspartic acid using L‐serine as a chiral precursor. Labeled serine, prepared biosynthetically was N‐protected by conversion to the N‐t‐Boc derivative. (N‐t‐Boc)‐[3−13C]Serine is cyclized to its β‐lactone which was treated with potassium [13C]cyanide to yield L‐β‐[3,4−13C2]cyanoalanine. Hydrolysis of the cyanoalanine yielded L‐[3,4−13C2]aspartic acid. Similarly, L‐[4−13C]aspartate was produced from L‐serine and K13CN. Using this route, the L‐enantiomer was produced in 96% excess.
One step synthesis of vanillin d3 (4‐hydroxy‐3‐(methoxy d3)‐benzaldehyde)
Authors: Schneider Serge , Rolando Christian 
Published: October 2006

AbstractA simple one step synthesis of deuteriated vanillin from 3,4‐dihydroxybenzaldehyde and iodomethane‐d3 in strongly basic medium is described.
Synthesis of [triazole‐3(5)‐14C]‐propiconazole stereoisomers
Authors: Hadjidemetriou Demetrios , Loeffler R. Thomas 
Published: October 2006

AbstractA preparation of all four stereoisomers of the fungicide and sterol biosynthesis inhibitor propiconazole (1‐[2‐(2,4‐dichlorophenyl)‐4‐propyl‐1,3‐dioxolan‐2‐ylmethyl]‐1H‐1,2,4‐triazole), labelled with [14C] in the triazole ring, is described.
14C‐labeling of a tetrahydroacridine, a novel CNS‐selective cholinesterase inhibitor
Authors: Nishioka Kazuhiko , Kamada Takeshi , Kanamaru Hiroshi 
Published: October 2006

Abstract9‐Amino‐8‐fluoro‐2, 4‐methano‐1,2,3,4‐tetrahydroacridine citrate (SM‐10888), a novel cholinesterase inhibitor, was labeled with carbon‐14 at C9 of the tetrahydroacridine ring for use in metabolic studies. Carbonation of 2,6‐difluorophenyllithium (3) with [14C]carbon dioxide gave the acid (4). Chlorination of 4 followed by treatment of the resulting acid chloride with ammonia afforded the amide (5). Dehydration of 5 with thionyl chloride and subsequent displacement reaction with ammonia gave the aminobenzonitrile (7). Condensation of 7 with the ketone (8) in the presence of anhydrous zinc chloride yielded the aminoacridine (9), which was treated with citric acid to afford [9‐14C]SM‐10888 (1). The overall yield of 1 was 37% from 2, and the specific activity was 1.35 GBq/mmol.
Synthesis of deuterium labelled hexenols
Authors: Brenstrum Timothy , Brimble Margaret A. , Rush Caroly N. J. , Shaw G. John , Reid David. C. W. 
Published: October 2006

AbstractHexenols are important flavour components of fruit and vegetables. We report the synthesis of cis‐3‐hexen‐1‐ol‐6,6,6‐2H3, hexen‐1‐ol‐6,6,6‐2H3, hexan‐1‐ol‐6,6,6‐2H3, cis–2‐hexen‐1‐ol‐6,6,6‐2H3 and trans‐2‐hexen‐1‐ol‐6,6,6‐2H3.
Synthesis of high specific activity tritium labeled (E)‐6‐(bromomethylene)‐tetrahydro‐3‐(1‐naphthalenyl)‐2H‐pyran‐2‐one as a selective probe for calcium‐independent phospholipase a2
Authors: Durley Richard C. , Parnas Barry L. , Weiss Randy H. 
Published: October 2006

AbstractThe synthesis of (E)‐6‐(bromomethylene)‐tetrahydro‐3‐([4‐3H]‐1‐naphthalenyl)‐2H‐pyran‐2‐one at a specific activity of 24.0 Ci/mmol is described. This probe was synthesized to determine whether (E)‐6‐(bromomethylene)‐tetrahydro‐3‐(1‐naphthalenyl)‐2H‐pyran‐2‐one inhibits calcium‐independent myocardial phospholipase A2 irreversibly via covalent modification. The material was synthesized in four steps from 1‐naphthalene acetic acid via [4‐3H]‐1‐naphthaleneacetic acid. The yield from [4‐3H]‐1‐naphthaleneacetic acid was 29.7%. The radiochemical purity of the HPLC‐purified final product was 99.5%.
Synthesis of N‐Acyl‐2‐amino‐2‐deoxy‐[1‐14C]‐glucoses as precursors for the biosynthesis of novel N‐acylneuraminic acids
Authors: Kayser Holger , Zeitler Reinhard , Hoppe Berthold , Reutter Werner 
Published: October 2006

AbstractN‐Propanoyl‐, N‐butanoyl‐, N‐pentanoyl‐, N‐hexanoyl‐, N‐heptanoyl‐ and N‐crotonoyl‐[1‐14C]‐D‐glucosamine were synthesized from [1‐14C]‐D‐glucosamine and their respective carbonic acid anhydrides as precursors for the biosynthesis of the corresponding N‐acyl neuraminic acids. The N‐acyl‐glucosamines are phosphorylated to their respective phosphate by N‐acetyl‐glucosamine kinase in a rat liver homogenate. These precursors may become valuable tools to investigate the biological role of the N‐acyl side chain of N‐acyl‐glucosamines and N‐acyl neuraminic acids which are components of glycoconjugates.
Marquage par 14C ET 13C de la N acetyl O6 benzyl guanosine
Authors: Madelmont J. C. , Cussac C. , Dupuy J. M. , Rapp M. , Labarre P. , Chabard J. L. , Maurizis J. C. , Sauzieres J. , Baudry J. P. , Godeneche D. , Veyre A. 
Published: October 2006

AbstractO6 Benzyl N acetyl guanosine a new inhibitor of O6 Alkyl Guanine transferase (O6AGT) was labelled by 14C and 13C on the benzyl methylen group in order to realize a pharmacokinetic study on nude mice grafted with human tumors.The labelling yield calculated from the precursor (Ba 14 or 13CO3) is in the range of 15%.
Marquage par 14C et 3H du 4,4‐dimethyl‐1‐(methylendioxy‐3,4 phenyl)‐1‐pentene‐3‐ ol ou stiripentol
Authors: Madelmont J. C. , Dupuy J. M. , Rapp M. , Labarre P. , Maurizis J. C. , Lepage F. , Veyre A. 
Published: October 2006

Abstract4,4‐dimethyl‐1‐(3‐4‐methylenedioxyphenyl)‐1‐pentene‐3‐ol or stiripentol was labelled by 14C and 3H.14C labelling was performed on the carbone 1 of the pentene group via a four steps procedure after the carbonatation. The radiochemical yield calculated from the precursor (Ba14CO3) is 28%.3H labelling was performed on the position 3 of the pentene chain by reduction of the corresponding cetone via NaBT4. The radiochemical yield calculated from the precursor (NaBT4) is 40%.
Synthesis of the new immunostimulating agent pidotimod (3‐L‐pyroglutamyl‐L‐thiazolidine‐4‐carboxylic acid) labelled with 14C‐ and 35S‐isotopes
Authors: Ferraboschi Patrizia , Grisenti Paride , Santaniello Enzo , Giachetti Claudio , Zanolo Giovanni , Signorelli Giovanni , Coppi Germano 
Published: October 2006

Abstract3‐L‐Pyroglutamyl‐L‐thiazolidine‐4‐carboxylic acid (Pidotimod), a new immunostimulating agent, has been prepared labelled with 14C and 35 isotopes starting from L‐[U‐14C]‐glutamic acid 5 and L‐[35S]‐cysteine hydrochloride 6, respectively. In the first synthesis, L‐[U‐14C]‐5 is converted into L‐[U‐14C]‐pyroglutamic acid 2, which was reacted with ethyl L‐thiazolidine‐4‐carboxylate 3 to afford the ester 4, in turn hydrolyzed to [14C]‐Pidotimod 1. In the second synthesis, L‐[35S]‐6 reacted with formaldehyde to give L‐[35S]‐thiazolidine‐4‐carboxylic acid 7, which was coupled with the activated ester of pyroglutamic acid, compound 8, to afford [35S]‐Pidotimod 1. The total activity of [14C]‐Pidotimod was 1.2 mCi (specific activity 5.52 mCi/mmol) and that of [35S]‐Pidotimod was 1.0 mCi (specific activity 9.43 mCi/mmol).
High specific activity steroids II: Microscale synthesis of norgestrel‐[9,11‐3H]
Authors: Huang Glenn T. , McCarthy Keith E. , Parnes Howard 
Published: October 2006

AbstractThe synthesis of the high specific activity (39 Ci/mmole) tritium labelled steroid norgestrel is described. A practical synthesis of the required substrate for tritium incorporation, 18‐methyl‐Δ9(11)‐estradiol‐3‐methyl ether (6), was developed from norgestrel itself. Following reduction with carrier‐free tritium gas, microscale conditions were employed for the conversion of the resulting labelled intermediate (7) back to norgestrel‐[9,11‐3H], including a selective in situ protection of the A‐ring ketone of 19‐norandrost‐4‐ene‐3,17‐dione (11).
The preparation of 2H and 3H‐labelled 7,9‐, and 7,10‐dimethylbenz[c]acridine by catalytic dehalogenation
Authors: Ye Yuerong , Holder Gerald M. , Duke Colin C. 
Published: October 2006

AbstractDeuterated and tritiated 7,9‐dimethylbenz [c] acridine, and 7,10‐dimethyl‐benz[c]acridine, labelled at the methyl groups, were prepared by catalytic dehalogenation of bromomethyl compouds. For each aza‐aromatic compound three brominated derivatives were prepared and characterized. Incorporation of deuterium occurred more readily at the 9‐ or 10‐methyl groups than the 7‐methyl groups suggesting a large isotope effect for catalytic deuteration.
Synthesis of tritium labelled oximes: 2‐pyridine aldoxime methiodide (2‐PAM) and 1‐(2‐hydroxyiminomethylpyridinium)‐1‐(4‐carboxyamidopyridinium)dimethylether dichloride (HI‐6), with high specific activity
Authors: Balan Ayala , Barness Itzhak , Amitai Gabriel 
Published: October 2006

AbstractSynthesis of two quaternary pyridinium oximes [3H]2‐PAM and [3H]HI‐6 (18 and 22 Ci/mmole, respectively) was performed by using unlabelled 6‐bromo 2‐pyridine aldehyde (I) as a common starting material. The labelling was based on a catalytic ring‐tritiation of 6‐bromo 2‐diethylketal pyridine followed by acid hydrolysis and reaction with hydroxylamine to yield 6‐[3H]2‐hydroxyiminomethyl pyridine (II). [3H]2‐PAM was obtained by reacting II with methyliodide and [3H]HI‐6 was prepared by alkylation of II with bischlorodimethylether followed by coupling to isonicotineamide. The radiochemical purity of [3H]2‐PAM and [3H]HI‐6 was 98% and at least 95% respectively.
An improved synthetic procedure for L‐3‐iodo‐α‐methyl tyrosine suitable for preparation in kit form
Authors: Trivedi Mahendra A , Carnochan Paul 
Published: October 2006

AbstractWe describe a modified method for the synthesis of radiolabelled L–3–iodo—α–methyl tyrosine (IMT) based on electrophilic iodination using KI and KIO3. Purification of the product using reverse phase HPLC gives reproducible radiochemical yields of 85% and chemical purity >99%. The method has been further modified and simplified for the preparation of IMT in kit form.
Synthesis and in vivo behavior of a copper‐64‐labeled dithiosemicarbazone derivative coupled to a dihydropyridine carrier
Authors: Saji Hideo , Saiga Akihiko , Iida Yasuhiko , Magata Yasuhiro , Yokoyama Akira 
Published: October 2006

AbstractThe dihyropyridine ⇄ pyridinium salt redox delivery system was used to develop a perfusion agent that could be labeled with a generator‐produced positron emitter 62Cu. A 64Cu‐labeled dithiosemicarbazone (DTS) molecule attached to a dihyropyridine carrier (PDTS‐DHC) was synthesized by the simple mixing of 64Cu acetate and Zn‐PDTS‐DHC. The latter was prepared by dithionite reduction of the Zn complex of a corresponding pyridinum precursor (PDTS‐QC+). When injected into mice, 64Cu‐PDTS‐DHC showed a high myocardial uptake and high heart‐to‐blood and heart‐to‐lung ratios. These results demonstrate that it may be possible to develop 62Cu‐PDTS‐DHC compounds as radiopharmaceuticals for myocardial perfusion studies using positron emission tomography.
An investigation into the catalytic deuteration and tritiation of dehydroproline9‐buserelin
Authors: Oehlke J. , Brankoff T. , Schmidt M. , Brudel M. , Kertscher U. , Berger H. 
Published: October 2006

AbstractFor optimizing the catalytic tritiation of peptides, the catalytic deuteration of buserelin and DhP9‐buserelin1 in DMA after reaction of DhP9‐buserelin were comparable in both solvents. The nonspecific incorporation of deuterium found after deuteration of buserelin was clearly lower after reaction in DMA. Tritiation of DhP9‐buserelin in DMA using 85% tritium gas, with conditions optimized by the deuteration experiments, resulted in a specific radioactivity of 1.3 TBq/mmol. 72 and 13 percent of the incorporated radioactivity were found to be associated with proline and histidine, respectively, after acidic hydrolysis.
Stereoselective synthesis of stable isotope labeled L‐α‐amino acids: The enzymatic preparation of 13C‐labeled L‐glutamic acids
Authors: Goux Warren J. , Rench Linda , Weber Denise S. 
Published: October 2006

AbstractWe have developed methods for the preparation of L‐glutamic acid, isotopically labeled with 13C, using commercially available purified enzymes. The procedure is sufficiently versatile that L‐glutamic acid may be labeled at any carbons or any combination of carbons using 13C‐labeled pyruvate, acetate and bicarbonate as isotopically labeled precursors. Using the strategy outlined, we have demonstrated the methodology using as an example the preparation of millimolar quantities of L‐[1‐13C], L‐[4‐13C], L‐[5‐13C] and L‐[1,3,4‐13C3]glutamic acid in a one‐pot incubation. We also outline methods for the preparation of 13C‐labeled L‐malate and citrate.
Preparation and biodistribution of a technetium cationic complex ‐ [TcIII(sacac)2en(PPh3)2]+
Authors: Vavouraki H. , Papadopoulos M. , Mastrostamatis S. , Varvarigou A. D. , Psilla M. , Chiotellis E. 
Published: October 2006

AbstractThe new, “mixed‐ligand”, TcIII‐N, N′‐ethylene‐bis‐(acetylacetone‐thioiminato)‐bis‐(triphenylphosphine)–hexafluorophosphate complex, corresponding oxo‐technetium (V) precursor with triphenylphoshine, in methanol. It was characterized by elemental analysis, IR, UV‐Vis and 1H NMR spectroscopy and HPLC. Biodistribution studies showed a considerable heart uptake, but rather slow blood clearance and hepatic elimination.
Synthesis of 15N and 17O labelled phosphoramide mustards
Authors: Ludeman Susan M. , Shulman‐Roskes Ellen M. , Gamcsik Michael P. , Hamill Terence G. , Chang Young H. , Koo Kyo I. , Colvin O. Michael 
Published: October 2006

AbstractThe cyclophosphamide metabolite phosphoramide mustard (PM) was synthesized with isotopic enrichment at each nitrogen and oxygen site. Sequential reaction of N,N‐bis(2‐chloroethyl)phosphoramidic dichloride [Cl2P(O)N(CH2CH2Cl)2] with benzyl alcohol and ammonia gave N,N‐bis(2‐chloroethyl)phosphorodiamidic acid phenylmethyl ester [BzO(H2N)P(O)N(CH2CH2Cl)2]. Catalytic hydrogenation of this benzyl ester followed by the addition of cyclohexylamine (CHA) provided PM as the CHA salt. Incorporation of 15NH3 into this general scheme gave PM with a 15NH2 moiety. Glycine‐15N was converted to bis(2‐chloro‐ethyl)amine‐15N hydrochloride which, in turn, provided for N,N‐bis(2‐chloroethyl)phosphoramidic‐15N dichloride. Use of this compound in the general synthetic pathway yielded PM°CHA with 15N in the mustard moiety. 17O‐Enriched PM was generated through the use of benzyl alcohol‐17O. To obtain the alcohol, labelled benzaldehyde was made by exchange with 17OH2 and was then reduced with sodium borohydride.
Radiation‐induced tritium labelling and product analysis
Authors: Peng C. T. 
Published: October 2006

AbstractBy‐products formed in radiation‐induced tritium labelling are identified by co‐chromatography with authentic samples or by structure prediction using a quantitative structure‐retention index relationship. The by‐products, formed from labelling of steroids, polynuclear aromatic hydrocarbons, 7‐membered heterocyclic ring structures, 1,4‐benzodiazepines, 1‐haloalkanes, etc. with activated tritium and adsorbed tritium, are shown to be specifically labelled and anticipated products from known chemical reactions. From analyses of the by‐products, one can conclude that the hydrogen abstraction by tritium atoms and the substitution by tritium ions are the mechanisms of labelling. Classification of the tritium labelling methods, on the basis of the type of tritium reagent, clearly shows the active role played by tritium atoms and ions in radiation‐induced methods.
Deuterium exchange labelling of substituted aromatics using [IrH2(Me2CO)2(PPh3)2]BF4
Authors: Heys J. R. , Shu A. Y. L. , Senderoff S. G. , Phillips N. M. 
Published: October 2006

AbstractDeuterium exchange labelling experimets were conducted on several series of compounds, including para‐substituted benzoate esters, para‐substituted N,N‐dimethylbenzamides, and mono‐para‐substituted benzophenones, using [IrH2(Me2CO)2(PPh3)2]BF4as catalyst and deuterium gas as the source of isotope. In most cases, labelling was efficient and regioselective, with deuterium appearing in the positions ortho to the carbonyl‐containing functional group. Apparent from the results of these experiments was that, in each case the para‐substituted rings were labelled more rapidly or to a greater extent than the corresponding unsubstituted rings, regardless of the identity of the substituent.