Synthesis of 1,2,3-Triazole 5-Chloroisatin Derivatives via Copper-Catalyzed 1,3-Dipolar Cycloaddition Reactions

A facile and simple protocol for the ‘Click\u27 cycloaddition of organic azides with N-propargylchloroisatine catalyzed by CuI, produces in good yields novel of 1,4-disubstituted 1,2,3-triazoles were obtained. Compared to the uncatalyzed cycloaddition, the yields are significantly improved in the presence of CuI as catalyst, without alteration of the selectivity. The regio- and stereochemistry of the cycloadducts has been corroborated by 1H, 13C NMR spectroscopy

Syntheses and Characterizations of Some New N-alkyl, Isoxazole and Dioxazole Derivatives of 5-Chloroisatin

N-alkyl and cycloadducts derivatives of 5-Chloroisatin were synthesized in good to excellent yields. The method evidences a selective N-alkylation when using 1,2-bis (2-chloroethoxy) ethane as efficient spacer at room temperature on the 5-Chloroisatin moiety. A general method for the 1,3-dipolar cycloaddition of 4-Chlorobenzaldoxime to alkynes provides a useful alternative route to get newisoxazole et dioxazole derivatives

Cognitive cues and visually induced motion sickness

The importance of cognitive processing of orientation cues in visually induced motion sickness and vection is often overlooked. Upright versus inverted visual scenes containing cues of different levels of salience were compared. METHODS: Panoramic scenes of 360 degrees were projected in the visual equivalent to the nauseogenic situation of rotating about an axis tilted from the vertical with a field of view of 84 degrees rotating at 0.2 Hz (72 degrees x s(-1)). Exposures were for 10 min or until moderate nausea developed. The design was counterbalanced repeated measures. Pilot Study: Subjects (N = 12) viewed visual conditions: a distant bland coastline scene as from an aircraft, tilted 30 degrees (Up); the same scene but inverted (Invert); and the scene morphed with no obvious orientation cues (Abstract). Main Experiment: Subjects (N = 22) viewed a city street scene containing numerous unambiguous and strong verticality cues under two conditions: upright (Up) and inverted (Invert), with 18 degrees tilt of rotational axis. RESULTS: Pilot Study: there were no significant differences between conditions in time (mean +/- SD min) to nausea endpoint (Up: 7.4 +/- 3.1; Invert: 7.1 +/- 3.1;Abstract: 7.8 +/- 2.4), nor for total symptom scores, nor for vection. Main Experiment: the upright scene was significantly more nauseogenic than the inverted, with shorter times to nausea endpoint (Up: 8.7 +/- 2.3; Invert: 9.2 +/- 2.2) and greater total symptom scores. Vection was marginally greater for Up than Invert. CONCLUSIONS: Salient and unambiguous higher order cognitive cues may modulate the development of motion sickness induced by optokinetic stimuli. There was no one-to-one correspondence between vection and motion sicknes

Establishing a bone bank in developing countries

No Abstrac

Cartographie et zonage de l'aléa d'inondation a Taza (Maroc). Application de la 'Methode Géomorphologique Integrée'.

La présente étude consiste à cartographier l'aléa d'inondation dans la zone périurbaine au nord de Taz

Cartographie et zonage de l'aléa d'inondation a Taza (Maroc). Application de la 'Methode Géomorphologique Integrée'.

La présente étude consiste à cartographier l'aléa d'inondation dans la zone périurbaine au nord de Taz