Search

Your search keyword '"Frangin, Y."' showing total 113 results
Start Over Author "Frangin, Y."
113 results on '"Frangin, Y."'

5. A selective radiobrominated cocaine analogue for imaging of dopamine uptake sites: Pharmacological evaluation and pet experiments

Author

Helfenbein, J., primary, Loc'h, C., additional, Bottlaender, M., additional, Emond, P., additional, Coulon, C., additional, Ottaviani, M, additional, Fuseau, C., additional, Chalon, S., additional, Guenther, I., additional, Besnard, J-C., additional, Frangin, Y., additional, Guilloteau, D., additional, and Maziere, B., additional

Published
1999
Full Text
View/download PDF

9. ChemInform Abstract: Synthesis and Ligand Binding of Nortropane Derivatives: N‐Substituted 2β‐Carbomethoxy‐3β‐(4′‐iodophenyl)nortropane and N‐(3‐ Iodoprop‐(2E)‐enyl)‐2β‐carbomethoxy‐3β‐(3′,4′‐disubstituted phenyl)nortropane. New High‐Affinity and Selective Compounds for the Dopamine Transporter.

Author

EMOND, P., primary, GARREAU, L., additional, CHALON, S., additional, BOAZI, M., additional, CAILLET, M., additional, BRICARD, J., additional, FRANGIN, Y., additional, MAUCLAIRE, L., additional, BESNARD, J.‐C., additional, and GUILLOTEAU, D., additional

Published
1997
Full Text
View/download PDF

28. Synthesis and crystal structure characterization of two new antibacterial agents: 512,3 and 2,4dichlorophenyl2phenylethyl2,4,6trichloropyrimidines

Author

Allouchi, H., Fellahi, Y., Héabert, C., Frangin, Y., and Courseille, C.

Abstract

The synthesis of 512,3dichlorophenyl2phenylethyl2,4,6trichloropyrimidine 4a and 512,4dichlorophenyl2phenylethyl2,4,6trichloropyrimidine 4b is described. These compounds were prepared by chlorination of the corresponding 5substituted barbituric acids obtained by treatment of the 5benzylidenebarbituric acids with benzylzinc bromide in the preceding step. These new trichloropyrimidines belong to a series of pyrimidine derivatives which show in vitroantibacterial activity against the undesirable human bacterial flora of the axilla and foot. The characterization of these compounds were performed by spectroscopy and Xray structure determination. Compounds 4aand 4bcrystallize in the monoclinic system. In the crystal of 4athere are two conformers A and B both of which are the same type of conformation, and are different from that found in the structure of 4b. The crystal cohesion results from numerous very week Van der Waals interactions.

Published
2003
Full Text
View/download PDF

29. Substituted Diphenyl Sulfides as Selective Serotonin Transporter Ligands:  Synthesis and In Vitro Evaluation

Author

Emond, P., Vercouillie, J., Innis, R., Chalon, S., Mavel, S., Frangin, Y., Halldin, C., Besnard, J.-C., and Guilloteau, D.

Abstract

A series of diphenyl sulfide derivatives substituted at the 1-, 2‘-, and 4‘-positions has been synthesized and evaluated for their in vitro affinities at the dopamine, serotonin (SERT), and norepinephrine transporters. The examination of Ki values revealed that most of these derivatives have high affinity and selectivity for the SERT. Moreover, substitutions at these positions differently influence the SERT binding:  (i) The nature of the substituent linked at the 1-position critically influences the SERT affinity. (ii) Functions containing heteroatom at the 2‘-position afford compounds with high SERT affinity. (iii) The nature of the substituent at the 4‘-position slightly influences the SERT affinity whereas steric effect markedly decreases the SERT affinity. From this series, the most SERT selective derivatives (such as 8b, 8c, and 8g) are now evaluated for their potential as positron emission tomography imaging agents when labeled with carbon-11.

Published
2002
Full Text
View/download PDF

32. Synthesis of (E)-N-(3-bromoprop-2-enyl)-2β-carbomethoxy-3β-(4'-tolyl) nortropane (PE2Br) and radiolabelling of [<SUP>76</SUP>Br]PE2Br: a potential ligand for exploration of the dopamine transporter by PET

Author

Helfenbein, J., Emond, P., Loc'h, C., Bottlaender, M., Ottaviani, M., Guilloteau, D., Mazière, B., Frangin, Y., and Chalon, S.

Abstract

In order to study the dopamine transporter by PET, we prepared (E)-N-(3-bromoprop-2-enyl)-2β-carbomethoxy-3β-(4'-tolyl) nortropane (PE2Br) and its radiobrominated analogue, PE2Br and [76Br]PE2Br were synthesized by bromodestannylation of the tributylstannyl derivative using either N-bromosuccinimide in THF or [76Br]NHBr with peracetic acid as oxidant respectively. After purification by HPLC, [76Br]PE2Br was obtained with a radiochemical yield of 80%, a radiochemical purity higher than 98% and a specific radioactivity of 20 MBq/nmol. Ex vivo autoradiographic studies in rats showed that 1 hour after i.v. injection of [76Br]PE2Br the highest accumulation in the brain was observed in the striata whereas no accumulation was observed in any other brain region. These results can be interpreted in terms of specific binding of [76Br]PE2Br to the dopamine transporter. Copyright © 1999 John Wiley & Sons, Ltd.

Published
1999
Full Text
View/download PDF

35. Synthesis and Ligand Binding of Nortropane Derivatives:  N-Substituted 2β-Carbomethoxy-3β-(4‘-iodophenyl)nortropane and N-(3-Iodoprop-(2E)-enyl)-2β-carbomethoxy-3β-(3‘,4‘-disubstituted phenyl)nortropane. New High-Affinity and Selective Compounds for the Dopamine Transporter

Author

Emond, P., Garreau, L., Chalon, S., Boazi, M., Caillet, M., Bricard, J., Frangin, Y., Mauclaire, L., Besnard, J.-C., and Guilloteau, D.

Abstract

Two novel series of iodinated N-substituted analogs of 2β-carbomethoxy-3β-(4‘-iodophenyl)tropane (β-CIT) and N-(3-iodoprop-(2E)-enyl)-2β-carbomethoxy-3β-(3‘,4‘-disubstituted phenyl)nortropane were synthesized. They were evaluated for their inhibitory properties on dopamine (DAT), serotonin (5-HTT), and norepinephrine (NET) transporters in rat brain homogenates using [3H]GBR-12935, [3H]paroxetine, and [3H]nisoxetine as specific ligands. All new N-substituted analogs of β-CIT exhibited higher DAT selectivity over both 5-HTT and NET than β-CIT. Moreover compounds with the N-substituents propynyl (6), crotyl (4), 2-bromoprop-(2E)-enyl (5), and 3-iodoprop-(2E)-enyl (3d) showed similar to higher DAT affinities than β-CIT (respectively 14, 15, 30, and 30 nM vs 27 nM). Compound 3d was found to be the most selective DAT agent of this series (5-HTT/DAT = 32.0 vs 0.1 for β-CIT). The N-(3-iodoprop-(2E)-enyl) chain linked to the tropane nitrogen was therefore maintained on the tropane structure, and phenyl substitution was carried out in order to improve DAT affinity. Ki values of N-(3-iodoprop-(2E)-enyl)-2β-carbomethoxy-3β-(3‘,4‘-disubstituted phenyl)nortropanes revealed that phenyl, 4‘-isopropyl, and 4‘-n-propyl derivatives weakly inhibited specific binding to DAT, whereas phenyl substitution with 4‘-methyl (3c), 3‘,4‘-dichloro (3b), and 4‘-iodo (3d) yielded high-DAT reuptake agents with increased DAT selectivity compared to β-CIT. These results demonstrate that the combination of a nitrogen and a phenyl substitution yields compounds with high affinity and selectivity for the dopamine transporter which are usable as SPECT markers for DA neurons.

Published
1997

42. N-(3-lodoprop-2E-enyl)-2beta-carbomethoxy-3beta-(3',4'-dichloro phenyl)nortropane (beta-CDIT), a tropane derivative: pharmacological characterization as a specific ligand for the dopamine transporter in the rodent brain

Author

Garreau L, Emond P, Belzung C, Denis Guilloteau, Frangin Y, Jc, Besnard, and Chalon S

Subjects
Male, Tomography, Emission-Computed, Single-Photon, Dopamine Plasma Membrane Transport Proteins, Membrane Glycoproteins, Nortropanes, Dopamine, Brain, Membrane Transport Proteins, Nerve Tissue Proteins, Motor Activity, Rats, Mice, Animals, Autoradiography, Rats, Wistar, Carrier Proteins
Abstract

N-(3-Iodoprop-2E-enyl)-2beta-carbomethoxy-3beta-(3',4'-dichl orophenyl)nortropane (beta-CDIT), a new iodinated tropane derivative, has been synthesized and radiolabeled with iodine. [125I]beta-CDIT was tested in vitro and ex vivo as a probe for the dopamine transporter site in the rat brain, and behavioral studies were performed in mice. Saturation studies in the striatum revealed that [125I]beta-CDIT bound to a single high-affinity site. The Kd value was 0.18 +/- 0.07 nM, and the corresponding Bmax value was 500 +/- 80 fmol/mg of protein. The pharmacological profile of specific [125I]beta-CDIT binding in the striatum was consistent with that of the dopamine transporter. In addition, competition studies in cerebral cortex regions with [3H]paroxetine and [3H]nisoxetine showed a very low affinity of beta-CDIT for the 5-hydroxytryptamine (Ki = 50 nM) and norepinephrine (Ki = 500 nM) transporters compared with beta-CIT (corresponding Ki values were 3 and 80 nM). In contrast, the competition of beta-CDIT with [3H]GBR 12935 in the striatal region (Ki = 29 nM) was of the same order of value as for beta-CIT (Ki = 27.5 nM). Behavioral experiments in mice showed that both beta-CDIT and beta-CIT induced stimulation of locomotor activity. Ex vivo autoradiographic studies in rats using [125I]beta-CDIT demonstrated high densities of [125I]beta-CDIT binding sites in areas known to be rich in dopaminergic innervation. Because of its high affinity and high selectivity for the dopamine transporter, [125I]beta-CDIT should be a valuable ligand for the exploration of the dopamine transporter with single-photon emission computed tomography.

Catalog

Books, media, physical & digital resources
See catalog results