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51.
OK Yoon WG Hwang JC Choe MS Kim 《Rapid communications in mass spectrometry : RCM》1999,13(14):1515-1521
A technique to investigate photodissociation kinetics on a nanosecond time scale has been devised for molecular ions generated by multiphoton ionization (MPI) using mass-analyzed ion kinetic energy spectrometry. The branching ratio or rate constant has been determined for the photodissociation of the n-butylbenzene, bromobenzene, iodobenzene, and aniline molecular ions generated by MPI at 266 nm. The ion internal energies have been estimated by comparing the measured kinetic data with the previous energy dependence data. The analysis has shown that only those molecular ions generated by two-photon ionization contribute to the photodissociation signals. Around half of the available energy has been found to remain as molecular ion internal energy in the two-photon ionization process. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
52.
Xiao Feng Jean-Charles Lancelot Herv Prunier Sylvain Rault 《Journal of heterocyclic chemistry》1996,33(6):2007-2011
The synthetic pathway leading to 4-H-furo[3,2-f]pyrrolo[1,2-a][1,4]diazepines is described in five steps starting from 2-hydroxyketones via 2-amino-3-furonitriles. 相似文献
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54.
α-Haloketones and -dibromides are converted to the corresponding ketones and alkenes respectively with nickel boride generated from sodium borohydride and nickel chloride. 相似文献
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56.
Sylvain Rault Yamien Effi Michel Cugnon De Sevricourt Jean-Charles Lancelot Max Robba 《Journal of heterocyclic chemistry》1983,20(1):17-21
The synthesis of pyrrolo[1,2-α]thieno[3,2-e]pyrazine and pyrrolo[1,2-α]-thieno[2,3-e]pyrazine is described. These syntheses could be achieved by intramolecular cyclization of 2- (and 3-) (1-pyrrolyl)-3- (and -2)-thienyl-amines obtained by hydrolysis of carbamates or by cleavage of the corresponding ureas. An original way giving better results was also studied via a Curtius rearrangement by reaction between the azide and aldehyde groupings. The synthesis of 2- (and -3)-2-formyl-1-pyrrolyl)-2- (and -3)-thenoylazide is described. 相似文献
57.
Bouillon A Voisin AS Robic A Lancelot JC Collot V Rault S 《The Journal of organic chemistry》2003,68(26):10178-10180
Regioselective and univocal Suzuki cross-coupling reactions performed on halopyridinyl boronic acids provide a flexible and versatile route to a multigram scale synthesis of 2,2'-dichloro-3,4'-bipyridine 14, which allows couplings with excess pyridin-3-yl boronic acid to give a new and efficient two-step rapid synthesis of nemertelline, the quaterpyridine neurotoxin isolated from a Hoplonemertine sea worm. 相似文献
58.
Jean Charles Lancelot Bertrand Letois Sylvain Rault Carmela Saturnino Max Robba Paolo De Caprariis 《Journal of heterocyclic chemistry》1992,29(6):1605-1608
The synthesis of cis-2,3-dihydro-3-hydroxy-2-(3-thienyl)[1,5]benzothiazepin-4(5H)-one derivatives is described starting from 2-aminothiophenol and methyl cis-(3-thienyl)glycidate. The structures were confirmed by 1H-nmr spectroscopy. 相似文献
59.
60.
Lepailleur A Bureau R Lemaître S Dauphin F Lancelot JC Contesse V Lenglet S Delarue C Vaudry H Rault S 《Journal of chemical information and computer sciences》2004,44(3):1148-1152
A definition of a pharmacophore for the 5-HT7 antagonists was carried out by searching the common chemical features of selective antagonists from the literature. A molecular design is described by analyzing the differences between this new pharmacophore and three other 3D serotonin pharmacophores previously described. This comparison led to the synthesis of a new series of potent 5-HT7 antagonists. 相似文献