bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of S‐[3H]‐DO‐710, a benzamide ligand of the D2‐dopamine receptor and of S‐[3H]‐azidosulpride, its photoactivable analog
Authors: Rognan D. , Mann A. , Hamdi P. , Wermuth C. C. , Sokoloff P. , Schwartz J. J. , Roy J. , Morgat J. J. 
Published: October 2006

AbstractThe preparation of the tritium labelled benzamides, S‐[3H]‐DO‐710 and S‐[3H]‐azidosulpride is reported. The synthesis involves enantioselective preparation of the pyrrolidinyl moiety, reductive tritiation of an allylic precursor and conversion of an amino, to an azido function.Both labelled ligands are D2‐dopaminergic antagonists, useful in binding experiments and to achieve covalent bonds after light exposure at the receptor site level.
Synthesis and enzymatic decarboxylation of 6‐bromo‐L‐dopa, a potential brain tracer for L‐dopa
Authors: Wong Michael , de Jesus Onofre T. 
Published: October 2006

AbstractDirect bromination of L‐dopa with stoichiometric amounts of molecular bromine was found to yield 6‐bromo‐L‐dopa as the sole product. This determination was made using liquid chromatography with electrochemical detector, mass spectroscopy, and proton NMR. 6‐Bromo‐L‐dopa was found to be a substrate of an isolated decarboxylase enzyme although the rate of decarboxylation was much slower than that for L‐dopa. These results suggest that a radiobrominated L‐dopa analog may be a suitable PET or SPECT tracer for L‐dopa in the brain.
Synthesis of 3H‐ and 14C‐cisapride
Authors: Janssen C. C. M. , Lenoir H. H. C. , Thijssen J. J. A. , Knaeps A. A. , Heykants J. J. P. 
Published: October 2006

AbstractCisapride, (±)‐cis‐4‐amino‐5‐chloro‐N[1‐[3(4‐fluorophenoxy)propyl]‐3‐methoxy‐4‐piperidinyl]‐2‐methoxybenzamide, is a new gastrokinetic drug with a potent stimulating effect on the gastrointestinal motor activity. Metabolic studies required the synthesis of cisapride labelled at one of the three major moieties. Hence, cisapride was tritiated either in the fluorophenyl moiety by means of reductive dehalogenation, or via reductive amination in the piperidine ring.14C‐Cisapride was labelled in the benzamide function. The title compounds were obtained at a specific activity of 17.0 Ci/mmol, 59.8 mCi/mmol and 7.8 mCi/mmol, respectively and with HPLC purities of > 98 %.
Perdeuteration at the 9,10‐positions of 9,10‐dibromoanthracene and anthracene‐d10
Authors: Pickering R. E. , Eisenbraun E. J. , Doughty D. , Strube M. M. , Gammon B. E. 
Published: October 2006

AbstractNa/D2O/THF is highly effective in perdeuteration of anthracene‐d10 and 9,10‐dibromoanthracene at the 9,10‐positions to give 9,10‐dihydro‐9,10‐d2‐anthracene‐d10 and 9,10‐dihydro‐9,9,10,10‐d4‐anthracene respectively.
Synthesis of tri‐, tetra‐, and penta‐deuterated forms of vitamin a
Authors: Robert Bergen H. , Furr Harold C. , Olson James A. 
Published: October 2006

AbstractThe synthesis of 20,20,20‐trideutero, 14,20,20,20‐tetradeutero, 12,14,20,20,20‐pentadeutero, and 10,19,19,19‐tetradeutero analogs of retinoic acid ethyl ester and retinyl acetate, by a modified Wittig‐Horner synthesis, is described. Deuterium was introduced by base‐catalyzed exchange into appropriate intermediates. The 10,19,19,19‐2H4‐vitamin A, because of its high isotopic integrity (>98% 2H4), is the preferred analog for biological studies of vitamin A metabolism.
Synthesis of c‐9‐14C‐1,8‐dihydroxy‐3‐carboxyanthraquinone
Authors: De Witte P. , Lemli J. 
Published: October 2006

AbstractThe synthesis of C‐9‐14C‐rhein is reported, 14CO2 is used as a 14C‐source. After preparing 14C‐1,8‐dimethoxy‐3‐methylanthraquinone by a condensation reaction, the product is demethylated and the 3‐methyl group converted to the corresponding 3‐carboxy group. The radio‐active yield of the total synthesis, starting with 1 Ci 14CO2 is 6,9% (6,9 mCi); 352 mg 14rhein is produced with a specific activity of 55,7 mCi/mmol.
Synthesis of f‐18 labelled fluoro‐melatonins and 5‐hydroxy‐fluoro‐tryptophans
Authors: Chirakal Raman , Sayer Brian G. , Firnau Gunter , Garnett E. S. 
Published: October 2006

AbstractReaction of dilute [F‐18]fluorine gas with either melatonin or 5‐hydroxy‐tryptophan in hydrogen fluoride at −70°C gives 6‐fluoro‐melatonin or 4‐ and 6‐fluoro‐5‐hydroxytryptophan. They are of potential use in Positron Emission Tomography to image the binding sites for melatonin and to study the metabolism of serotonin.
Synthesis of [14C]‐labelled AY‐30,068
Authors: Hicks D. R. , Hangeland J. J. , Mobilio D. , Delange B. 
Published: October 2006

Abstract[14C]AY‐30,068 (cis‐1,8‐diethyl‐2,3,4,9‐tetrahydro‐4‐(2‐propenyl)‐1H‐carbazole‐1‐acetic acid), a potent analgesic agent, was prepared by incorporating [14C]methyl iodide via a Wittig reaction. The intermediate aldehyde was synthesized in six steps from cis‐1‐ethyl‐2‐oxo‐4‐(2‐propenyl)cyclohexaneacetic acid methyl ester. Three batches of the [14C]labelled AY‐30,068 were produced, giving a combined overall yield of 9% from [14C]methyl iodide (sp. act. 51.2, 17.7 and 4.4 μCi/mg; 97.5, 98.3, and 98.6% radiochemcical purity, respectively).
Synthesis of D/L‐ and L‐SE‐[methyl‐11C]selenomethionine
Authors: Någren Kjell , Långström Bengt 
Published: October 2006

AbstractThe syntheses of D/L‐ and L‐Se‐[methyl‐11C]selenomethionine are reported. The Se‐benzyl selenohomocysteines were deprotected in sodium/liquid ammonia and the selenide anions generated in situ were alkylated with [11C]methyl iodide to give, after purification by LC, the products in 80 to 85 % radiochemical yield, with a radiochemical purity higher than 99 % within 30 min and with a specific radioactivity of 20 to 200 mCi/μmol. The enantiomeric purity of the L‐compound, determined by LC, was higher than 99 %.
Synthesis of two S‐(methyl‐3H)‐labelled enkephalins and S‐(methyl‐14C)substance P
Authors: Någren Kjeli , Franzèn Henry M. , Ragnarsson Ulf , Långström Bengt 
Published: October 2006

AbstractThe synthesis of 3H‐labelled Met‐enkephalin and Tyr‐D‐Ala‐Gly‐Phe‐Met‐NH2 (DALA) and 14C‐labelled Substance P (SP) from previously described, fully protected intermediates is reported. The labelled peptides were prepared by methylation with (3H)‐ or (14C)methyl iodide of the sulphide anions formed on deprotection of the corresponding S‐benzyl‐homocysteine precursors with sodium in liquid ammonia. After purification by LC, the labelled peptides were obtained in radiochemical yields in the range of 9 to 24 % with a radiochemical purity higher than 97%. The specific radioactivities of the 3H‐ and 14C‐labelled products, corresponding to the labelled methyl iodides used, were 80 mCi/μmol and 60 μCi/‐μmol, respectively.
Synthesis of three 11C‐labelled methionine‐containing enkephal in analogues
Authors: Någren Kjell , Ragnarsson Ulf , Långström Bengt 
Published: October 2006

AbstractThe synthesis of three S‐[methyl‐11C]‐labelled enkephal in analogues, iyr‐D‐Ala‐Gly‐Phe‐Met‐NH2, Tyr‐D‐Ala‐D‐Ala‐Phe‐Met‐NH2 and Tyr‐D‐Met‐Gly‐Phe‐Pro‐NH2, from the corresponding S‐benzyl‐homocysteine‐containing peptides is reported. The protected pentapeptide amides were prepared by (3+2) fragment condensations in solution. These peptides were subsequently deprotected with sodium in liquid ammonia and the sulphide anions formed alkylated with [11C]‐methyl iodide to give the S‐[methyl‐11C]‐labelled enkephalins. After purification by preparative LC, these labelled peptides were obtained in 55 to 75 % radiochemical yield, decay corrected, based on the [11C]methyl iodide produced, within 30‐40 min from start of the synthesis of this reagent. The radiochemical purities of the products were higher than 98 %, and the specific activity was in the order of 20‐200 mCi/μmol.
Preparation of carbon‐11 labelled prazosin, a potent and selective α1‐adrenoreceptor antagonist
Authors: Ehrin Erling , Luthra Sajinder K. , Crouzel Christian , Pike Victor W. 
Published: October 2006

AbstractThe α1‐adrenoreceptor antagonist, Prazosin : 2‐[4‐(2‐furoyl) piperazin‐1‐yl]‐4‐amino‐6,7‐dimethoxyquinazoline, has been labelled with carbon‐11 for in vivo studies of α1‐adrenoreceptors using positron emission tomography. The preparation of [2‐11C] furoyl chloride, from cyclotron‐produced [11C] carbon dioxide, and its reaction with the secondary amine, 2‐(piperazin‐1‐yl)‐4‐amino‐6,7‐dimethoxyquinazoline, provides a fast (35 min) route to carbon‐11 labelled prazosin in high radiochemical yield (30‐40 %, decay‐corrected) with high specific activity (26‐37 GBq/μmol, 0.7‐1.0 Ci/μmol).
Synthesis of 1‐([1‐14C] cyclohexyloxycarbonyloxy) ethyl 7β‐[2‐(2‐aminothiazol‐4‐YL)acetamido]‐3‐[[[1‐(2‐dimethylamino‐ethyl)‐1H‐tetrazol‐5‐YL]thio]methyl]ceph‐3‐EM‐4‐carboxylate dihydrochloride ([14C]SCE‐2174)
Authors: Watanabe Masazumi , Tada Norio , Imanishi Masayuki , Yamaoka Masayoshi 
Published: October 2006

Abstract1‐(Cyclohexyloxycarbonyloxy)ethyl 7β‐[2‐(2‐amino‐thiazol‐4‐yl)acetamido]‐3‐[[[1‐(2‐dimethylaminoethyl)‐1H‐tetrazol‐5‐yl]thio]methyl]ceph‐3‐em‐4‐carboxylate dihydrochloride (SCE‐2174), a new orally active cephalosporin, was labeled with carbon‐14 starting from [1‐14C]cyclohexanol (1). 1‐Chloroethyl [1‐14C]cyclohexyl carbonate (3) obtained by acylation of 1 with 1‐chloroethyl chloroformate (2) was converted to iodide (4) which was condensed with the potassium salt of Cefotiam (5). [14C]SCE‐2174, having a specific activity of 672 MBq/mmol, was obtained in 13% overall radiochemical yield and had a radiochemical purity of 92%.
Synthesis of six specifically deuterated analogs of 1,2‐dibromo‐3‐chloropropane
Authors: Omichinski James G. , Nelson Sidney D. 
Published: October 2006

AbstractThe convenient preparation of six selectively deuterated analogs of 1,2‐dibromo‐3‐chloropropane have been described. The compounds were prepared by direct chlorination of the correspondingly deuterated 2,3‐dibromopropanol derivatives using N‐chlorosuccinimide and triphenylphospine. Spectral analysis revealed that the isotope incorporation was high and specific in all cases.
Synthesis of deuterated 1,2,3,4‐tetrahydroisoquinolines
Authors: Meese Claus O. , Ebner Thomas 
Published: October 2006

AbstractThe synthesis of five 1,2,3,4‐tetrahydroisoquinolines (2), which were either randomly labelled (1,1,3,3,4,4‐2H6,2b) or regioselectively labelled (1,1‐2H2,2c; 3,3‐2H2, 2d; 4,4‐2H2, 2e) from isoquinoline (4), indan‐2‐one (7), and phenylacetonitrile (11) is described. These deuterated bases were used in the preparation of labelled analogues of the antihypertensive agent debrisoquine.
The synthesis of deuterium labeled T‐2 toxin
Authors: Michaud Dennis P. , Karger B. L. , Vouros Paul 
Published: October 2006

AbstractWe report the synthesis of isotopically pure trideuteriated T‐2 toxin, a useful internal standard for mycotoxin analysis. Peracetylation of HT‐2 toxin with hexadeuteriated acetic anhydride, followed by selective hydrolysis of the C‐3 acetate afforded the desired compound in good yield.
Effects of reaction conditions on rates of incorporation of no‐carrier added F‐18 fluoride into several organic compounds
Authors: Korguth Ml , Degrado Tr , Holden Je , Gatley Sj 
Published: October 2006

AbstractApparent rate constants (fractional incorporation per minute per mole of organic reactant) were determined for reaction of no‐carrier added F‐18 fluoride with several aliphatic and aromatic substrates in acetonitrile or DMSO. No large differences were seen between tetraethylammonium and potassium Kryptofix‐2,2,2 as supporting cation. Three hexose derivatives with triflate or cyclic sulfate leaving groups all gave apparent rate constants (obtained by dividing fractional incorporation by time in minutes and by molar concentration of reactant) near 0.4 at 23° and 5 at 55°. An aliphatic iodide reacted ten times more slowly. Aromatic substrates tested showed a wide range of rate constants from >50 at 23° (isotope exchange in 2,4‐dinitrofluorobenzene) to 0.6 at 134° (p‐nitroacetophenone).
Labeling of a serotoninergic ligand with 18F : [18F] setoperone
Authors: Crouzel C. , Venet M. , Irie T. , Sanz G. , Boullais C. 
Published: October 2006

AbstractSetoperone has been labeled with 18F to visualize the serotoninergic receptors by positron emission tomography. The synthesis is carried out by a nucleophilic substitution from a nitro derivative of setoperone with 18F−. The synthesis of nitro‐derivative is described as well as the different trials of recovery of ion 18F− from neon or aqueous target. The considered technique of labeling allow to obtain from 7.4 GBq (200 mCi) 18F, 1.5 to 2 GBq (40–50 mCi) of [18F]setoperone, 110 minutes after the end of bombardment. The specific activity obtained from this quantity of radioactivity is about 37 GBq/μMol (1 Ci/μMol).
Alternative synthesis of no‐carrier‐added 2‐deoxy‐2‐[18F]fluoro‐D‐glucose using [18F] fluoride ion
Authors: Haradahira Terushi , Maeda Minoru , Kojima Masaharu 
Published: October 2006

AbstractTwo alternative routes to no‐carrier‐added synthesis of 2‐deoxy‐2‐[18F]fluoro‐D‐glucose (2‐18FDG) involving nucleophilic displacements of methyl 3‐O‐benzyl‐4,6‐O‐benzylidene‐2‐O‐(trifluoromethanesulfonyl) ‐β‐D‐mannopyranoside (1) and 1,6‐anhydro‐3, 4‐di‐O‐benzyl‐2‐O‐(trifluoromethanesulfonyl)‐β‐D‐mannopyranose (2) are described. The triflates (1 and 2) reacted with aminopolyether (Kryptofix 222) supported potassium [18F]fluoride and tetra‐n‐butylammonium [18F]fluoride in acetonitrile to give methyl 3‐O‐benzyl‐4,6‐O‐benzylidene‐2‐deoxy‐2‐[18F] fluoro‐β‐D‐glucopyranoside (3) and 1,6‐anhydro‐3,4‐di‐O‐benzyl‐2‐deoxy‐2‐[18F] fluoro‐β‐D‐glucopyranose (4), respectively. The displacement yield with 1 was consistently higher than that with 2. Hydrolysis of 3 with 6N HCl, followed by passage through an ion retardation resin column and a neutral alumina column, gave 2‐18FDG in 34–43% overall radiochemical yield without correction for decay. Removal of the protecting groups from 4 with 6N HCl or 50% CH3SO3H led to incomplete hydrolysis. The total preparation time was about 80 min from start of the radiofluorination.
Synthesis of 14C‐labeled stepholidine
Authors: Liu Yang , Xin Zhang 
Published: October 2006

Abstract(8‐14C)Stepholidine was synthesized by Mannich condensation of 7‐benzyloxy‐1‐(4‐benzyloxy‐3‐hydroxybenzyl)‐6‐methoxy‐1,2,3,4‐ tetrahydroisoquinoline (2) with (14C)formalehyde at pH 6.4 followed by methylation and debenzylation in 32% radiochemical yield.
The comparative synthesis of 18F‐fluorophenylalanines by electrophilic substitution with 18F‐F2 and 18F‐AcOF
Authors: Murakami M. , Takahashi K. , Kondo Y. , Mizusawa S. , Nakamichi H. , Sasaki H. , Hagami E. , Iida H. , Kanno I. , Miura S. , Uemura K. 
Published: October 2006

AbstractFluorination with 18F‐F2 and 18F‐AcOF were compared for the synthesis of 18F‐fluorophenylalanines. L‐phenylalanine in CF3COOH trapped 18F‐AcOF more effectively than 18F‐F2. The main product was ortho‐18F‐fluorophenylalanine when 18F‐AcOF was used as a reagent. Lower radiochemical yield of 18F‐fluorophenylalanines and significant formation of by‐product were observed in the case of 18F‐F2.
Synthesis of [14C]‐labelled dihydropyridine calcium channel entry blockers: Nicardipine‐[4‐14C] and RS‐93522‐[4‐14C]
Authors: Parnes Howard , Huang Glenn T. , Shelton Emma J. 
Published: October 2006

AbstractThe Hantzsch synthesis has been applied to the general preparation of 4‐aryl‐dihydropyridines labelled in the metabolically stable 4‐position of the dihydropyridine ring. The synthesis is based on the preparation of a key common intermediate, m‐nitrobenzaldehyde‐[formyl‐14C], in high yield from Ba14CO3.
A short radiosynthesis of natural juvenile hormone III, methyl [12‐3H]‐(10R)‐10,11‐epoxyfarnesoate
Authors: Eng Wai‐Si , Prestwich Glenn D. 
Published: October 2006

AbstractA new asymmetric synthesis of natural JH III from methyl farnesoate allows introduction of tritium from sodium borotritide into the 12‐methyl group. Selective allylic oxidation followed by Sharpless epoxidation of the (E)‐allylic alcohol gives an epoxy alcohol (>97% e.e.), which is oxidized to the aldehyde. Sodium borotritide (65 Ci/mmol) reduction of the aldehyde is followed by tosylation, iodide displacement, and cyanoborohydride displacement to give [3H]‐(10R)‐JH III, specific activity 14 Ci/mmol.
Synthesis of [14α, 15α‐3H]‐norgestrel
Authors: Wagner H. , Römer J. 
Published: October 2006

AbstractThe preparation of the well‐known gestogen norgestrel in a tritium labelled form is described. Starting material was 18‐methyl‐3‐methoxy‐estra‐1,3,5(10),8,14‐pentaen‐17B‐ol acetate. In a four step synthesis 17α‐ethinyl‐17B‐hydroxy‐18‐methyl‐[14α,15α‐3H]‐estr‐4‐en‐3‐one was obtained with a specific activity of 52 Ci/mmol and a radiochemical purity > 99 %.
A chiral synthesis of (2S, 3S)‐phenylalanine‐3‐2H via boronic esters
Authors: Matteson Donald S. , Beedle Ellen C. , Christenson Erik , Dewey Michael A. , Peterson Mark L. 
Published: October 2006

AbstractReduction of (s)‐pinanediol (S)[(phenyl) (chloro)‐methyl]boronate (1) with lithium triethylborodeuteride yielded (s)‐pinanediol (R)‐[(phenyl)methyl]boronate‐α‐2H (2). The chiral purity of 2 was measured via peroxidic oxidation to (S)‐benzyl alcohol‐α‐2H (3), which was analyzed with an NMR chiral shift reagent. (Dichloro‐methyl)lithium converted 2 to (s)‐pinanediol (1S,2S)‐1‐chloro‐2‐phenylethylboronate‐2‐2H (4), which with sodium azide yielded (s)‐pinanediol (1R,2S)‐1‐azido‐2‐phenylethylboronate‐2‐2H (5). (Dichloromethyl) lithium with 5 yielded (s)‐pinanediol (1S, 2S,3S)‐1‐chloro‐2‐azido‐3‐phenylpropylboronate‐3‐2H (6), which was oxidized by sodium chlorite to (2S,3S)‐2‐azido‐3‐phenylacetic acid‐3‐2H (7). Hydrogenation of 7 yielded (2S,3S)‐phenylalanine‐3‐2H (8) in high diastereomeric and enantiomeric purity.
Synthesis of 14C‐labeled and stable isotope‐labeled CGS 16617
Authors: Chaudhuri Naba K. , Markus Bohdan , Sung Ming‐Sang 
Published: October 2006

AbstractThe synthesis of a 14C‐labeled and two stable isotope‐labeled analogs of CGS 16617 is described. The synthetic method involved the preparation of tetrahydro‐3‐bromo‐1‐benzazepin‐2‐one, labeled with a 14C or four deuterium atoms, followed by introduction of two side chains at 1‐ and 3‐positions. The labeled bromobenzazepinones were prepared by Beckmann rearrangement of bromooximes of α‐tetralones, obtained by cyclization of labeled benzenebutanoic acids. The 14C‐labeled acid was prepared by hydrolysis of the nitrile, prepared by reaction of 3‐bromopropylbenzene and K14CN. The tetradeutero acid was prepared from ethyl phenylpropynoate by catalytic reduction of the triple bond with deuterium gas, followed by reduction of the deuterated ester with lithium aluminum hydride and conversion of the resulting alcohol into the carboxylic acid. The acetic acid side chain was introduced by N‐alkylation with ethyl bromoacetate or ethyl bromoacetate‐1,2‐13C2 followed by hydrolysis, and the L‐lysine side chain, by reaction with L‐(−)‐3‐amino‐caprolactam followed by hydrolysis of the caprolactam ring.
Synthesis of carbon‐14 labeled (±)‐2‐methyl‐3,3‐diphenyl‐3‐propanolamine (2‐MDP)
Authors: De Costa Brian , Thurkauf Andrew , Jacobson Arthur E. , Rice Kenner C. 
Published: October 2006

AbstractThe preparation of 14C labeled (±)‐2‐methyl‐3,3‐diphenyl‐3‐propanolamine (3) from [14C]‐carbonyl‐benzophenone is described.
The synthesis of [14C] and [3H2] SK&F l‐94901. A novel thyromimetic
Authors: Crowe A M , Lawrie K W M , Saunders D 
Published: October 2006

AbstractA novel thyromimetic SK&F L‐94901, L‐3,5‐dibromo‐3′‐(6‐oxo‐1, 6‐dihydro pyridazin‐3‐ylmethyl) thyronine, has been labelled with 14C and 3H for drug metabolism and nuclear binding studies. A six stage synthesis from [β‐14C] tyrosine is described. The overall radiochemical yield was 13.7%.Syntheses of [3H2] SK&F L‐94901 of 1.22Ci mmol−1 and 13.9Ci mmol−1 are described, and the instability of these compounds noted.
35S‐labelled thiophosphorylated derivative of inositol trisphosphate
Authors: Folk P. , Kmoníčková E. , Krpejšová L. , Strunecká A. 
Published: October 2006

AbstractWe have prepared the [35S] thiophosphate labelled inositol trisphosphate and [32P]phosphate labelled inositol trisphosphate (IP3) from human erythrocytes. These compounds were used as substrates for the inositol trisphosphate 5‐phosphomonoesterase assay in human erythrocyte membranes. During 60 min incubation with the enzyme, the 35S‐labelled IP3 was not hydrolyzed, meanwhile the 32P‐labelled IP3 was broken down to 19.8 ± 2.4 %. This suggests that due to the presence of thiophosphate in the molecule the 35S‐labelled IP3 cannot serve as substrate for inositol trisphosphate 5‐phosphomonoesterase. The [35S] thiophosphorylated derivative thus represents a nonhydrolyzable analogue of IP3 and could be used in the study of its second messenger role.
Autoradiography with photographic paper of thin‐layer chromatograms of radiocarbon‐labelled compounds
Authors: Sugimoto Yasuo , Ohta Yoshihiro , Tamaoki Bun‐Ichi 
Published: October 2006

AbstractBy exposing a thin‐layer chromatogram of 4‐14C‐labelled steroids directly onto a sheet of photographic paper, evidence was obtained on the distribution of radioactivity on the chromatogram. This method offers a relatively easy way to make a copy for publication and recording.
Labelling of a new serotoninergic ligand : [18F]ritanserin
Authors: Crouzel C. , Venet N. , Sanz G. , Denis A. 
Published: October 2006

AbstractRitanserin has been labelled with 18F to visualize the serotoninergic receptors by Positron Emission Tomography (PET). The synthesis was carried out by a nucleophilic substitution of a nitro substituent of a nitrophenylketone by 18F− and then addition of a Grignard reagent to the ketone followed by dehydration of the tertiary alcohol so formed.The total time to have [18F]ritanserin ready for injection into a patient was 150 minutes (after the end of bombardement for the 18F production [18O (p,n) 18F]).The labelling technique described was used to obtain 1.1 to 1.5 GBq (30 to 40 mCi) of [18F]Ritanserin with a specific activity of 44 GBq/μmol (1.2 Ci/μmol) starting from 18.5 GBq (500 mCi) 18F.
Isosteres Oxygenes d'Hydroxy‐di‐n‐Propylaminotetralines Syntheses de Monomethoxy et Monohydroxy‐ (DI‐N‐Propylamino)‐3 Chromannes [n‐Propyl‐3H] Racemiques: Nouveaux Radioligands des Sites de Liaison Serotoninergiques 5‐HT1a et Dopaminergiques D2
Authors: Cossery J. M. , Perdicakis C. , Coudert G. , Guillaumet G. , Pichat L. 
Published: October 2006

AbstractOxygen Isosteres of hydroxy‐di‐n‐propylaminotetralines. Syntheses of racemic monomethoxy and monohydroxy‐3‐(di‐n‐[3H‐propyl] amino) chromanes: new Radioligands for 5–HT1A and D2 receptors sites labelling.Condensation of monomethoxy salicylaldehydes: 4a–d with nitroethanol gave methoxy‐3‐nitro‐2H chromenes 5a–d which were reduced with LAH into methoxy‐3‐amino chromans 6a–d. Two syntheses of 2‐hydroxy‐6‐methoxy‐benzal‐dehyde: 4a were described. N‐alkylations of 6a–d were carried out a/ by Borch procedure b/ by n‐propylation with propyl iodide in presence of bases c/ by allylation in presence of bases. Methoxy‐3‐(diallyl‐amino) chromans: 13a–d were catalytically reduced with hydrogen (Pd/C in methanol) into mixtures of methoxy‐3 (di‐n‐propylamino) chromans 2a–d and methoxy‐3‐ (n‐propylamino) chromans resulting from the hydrogenolysis of one allyl group.Methoxy‐3‐dialkylamino chromans 2a–d and 13a were O‐demethylated either by boiling 48% HBr or by BBr3 in CH2Cl2.Catalytic hydrogenation with tritium of precursors 13a–d and15a in methanol in presence of 10% Pd/C gave [3H] – 5. OH‐DPLC: 3a; [3H] 5. OMe‐DPAC: 2a and the isomers: 2b‐2d which were purified by HPLC, analyzed by reversed HPLC, 3H‐NMR, M.S. (spec. radioactivity: 37.2‐80 Ci/μMole. Radiochemical purity: 98.3–99.6%).