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101.
A facile synthetic route to the new 2-TIPS-oxazol-5-ylboronic acid pinacol ester was described herein. Its reactivity toward Suzuki cross-coupling reaction was studied to provide various 5-(het)aryloxazoles. A wide range of functions on the aryl moiety are tolerated. 相似文献
102.
103.
Bureau R Daveu C Lemaître S Dauphin F Landelle H Lancelot JC Rault S 《Journal of chemical information and computer sciences》2002,42(4):962-967
A definition of a pharmacophore for the 5-HT4 antagonist was carried out by considering a three-dimensional model which correlates the chemical structures of series of antagonists with their biological affinities. A molecular design is described by analyzing the differences between two 3D serotonin pharmacophores. This successful structural modification demonstrates the efficiency of this approach to design new serotonin ligands. 相似文献
104.
François-Xavier Le FoulonEmmanuelle Braud Frédéric FabisJean-Charles Lancelot Sylvain Rault 《Tetrahedron》2003,59(50):10051-10057
This paper describes a general procedure for the synthesis of new substituted thiaisatoic anhydrides or 6- or 7-aryl-1H-thiéno[3,2-d][1,3]oxazine-2,4-diones 3a-j and 4a-f. They were synthesized in large scale under microwave heating conditions with high yields. The reactivity vs nucleophilic reagents of these compounds was studied and permitted to develop a simple combinatorial procedure to synthesize a library of new thiophene ureidoacids 7a-j and 8a-j. 相似文献
105.
106.
Hannu?TiitinenEmail author Anna?Mari?M?kel? Ville?M?kinen Patrick?JC?May Paavo?Alku 《BMC neuroscience》2005,6(1):62
Background
The cortical activity underlying the perception of vowel identity has typically been addressed by manipulating the first and second formant frequency (F1 & F2) of the speech stimuli. These two values, originating from articulation, are already sufficient for the phonetic characterization of vowel category. In the present study, we investigated how the spectral cues caused by articulation are reflected in cortical speech processing when combined with phonation, the other major part of speech production manifested as the fundamental frequency (F0) and its harmonic integer multiples. To study the combined effects of articulation and phonation we presented vowels with either high (/a/) or low (/u/) formant frequencies which were driven by three different types of excitation: a natural periodic pulseform reflecting the vibration of the vocal folds, an aperiodic noise excitation, or a tonal waveform. The auditory N1m response was recorded with whole-head magnetoencephalography (MEG) from ten human subjects in order to resolve whether brain events reflecting articulation and phonation are specific to the left or right hemisphere of the human brain. 相似文献107.
Yamien Effi Sylvain Rault Jean-Charles Lancelot Max Robba 《Journal of heterocyclic chemistry》1987,24(2):431-435
5-Aminopyrrolo[1,2-a]thieno[2-3-3]pyrazine derivatives were obtained by intramolecular cyclisation of N3(1-pyrrolyl)-2-thienylurea derivaties. Synthesis of these latter compounds was achieved from 2-(1-pyrrolyl)-3-thenoylazide via a curtius rearrangement. The H nmr spectra are discussed. 相似文献
108.
Jean-Marie Gazengel Jean-Charles Lancelot Sylvain Rault Max Robba 《Journal of heterocyclic chemistry》1989,26(4):1135-1139
The synthesis of dihydropyrimidinocarbazoles 12,15 and 18 was achieved by cyclization of tetrahydrocarbazolones with triformamidomethane. The oxidation with potassium permanaganate of dihydropyrimidinocarbazoles gave the pyrimidinocarbazoles 13,16 and 19. The application of the Sandemeyer reaction to amiononitrocarbazoles gave cyanonitrocarbazoles which could be reduced to aminocyanocarbazoles 1 and 7. Intramolecular cyclization of the carbazoles 1 and 7 afforded 3,4-dilhydro-4-oxo-6H-pyrimidino[5,4-b]carbazole 2 and 1,2-dighydro-1-oxo-6H-pyrimidino[5,4-b]carbazole 10 was obtained by cyclization of quinazolinyl hydrazone 9 with hydrochloric acid and acetic acid. The structure of the derivatives was determined by 1H-nmr and the Overhauser effect. 相似文献
109.
Blewitt G LoSecco JM Bionta RM Bratton CB Casper D Chrysicopoulou P Claus R Cortez BG Errede S Foster GW Gajewski W Ganezer KS Goldhaber M Haines TJ Jones TW Kielczewska D Kropp WR Learned JG Lehmann E Park HS Reines F Schultz J Seidel S Shumard E Sinclair D Sobel HW Stone JL Sulak L Svoboda R van der Velde JC Wuest C 《Physical review letters》1985,55(20):2114-2117
110.