In the present study, some new bis-imidazole derivatives have been prepared through four-components condensation of 2,6-bis (4-aminophenyl)-4-p-tolylpyridine, benzaldehyde derivatives, benzil and ammonium acetate in presence of acetic acid. The present methodology offers several advantages such as good yields, simple procedure, milder conditions and the possibility of introducing a v...

Thiamine hydrochloride (Vitamin-B1) has been utilized as an effective biodegradable catalyst for the one pot synthesis of polyhydroquinoline derivatives via four component reaction of dimedone, aldehyde, ethylacetoacetate and ammonium acetate in ethanol under mild conditions. The method presented here offers several advantages over reported procedures in terms of environmentally benign catalyti...

The title trihalogenated nitro-benzene derivatives, C6H2Br3NO2 and C6H2Br2INO2, crystallize in triclinic and monoclinic cells, respectively, with two mol-ecules per asymmetric unit in each case. The asymmetric unit of the tri-bromo compound features a polarized Br(δ+)⋯Br(δ-) inter-molecular halogen bond. After substitution of the Br atom in the para position with respect to the nitro group, the...

We address the problem of egomotion estimation for a monocular observer moving under arbitrary translation and rotation, in an unknown environment. The method we propose is uniquely based on the spatio-temporal image derivatives, or the normal ow. We introduce a search paradigm which is based on geometric properties of the normal ow eld, and consists in considering a family of search subspaces ...

In this paper we present the convenient syntheses of seven new phenyl hydrazin derivatives 8 (a-h). For this purpose, acenaphtho [1,2-e]-1,2,4-triazine-9(8H)-thione (3) was prepared, starting from acenaphthylene-1, 2-dione (1) and thiosemicabazide in good yield. The reaction of (3) with benzyl chloride resulted to synthesis of 9-(benzylthio)-acenaphtho[1,2-e]-1,2,4-triazines (5) that reacted wi...

A new series of N-(5-Mercapto-1,3,4-thiadiazol-2-yl)-2-phenylacetamide derivatives (3a-3j) were synthesized via an amidation reaction using EDC and HOBt in acetonitrile solvent at room temperature condition. Chemical structures were characterized by 1H NMR, IR and MS spectroscopic methods and related melting points were also determined. The anticancer activity was evaluated using MTT procedure ...

An efficient synthesis of trialkyl (E)-3-(3-Oxo-2-3,4-dihydro-2-(1H)-quinoxalinylidene)-prop-1-ene-1,2,3-tricarboxylate derivatives via a simple three-component reaction between benzene-1,2-diamines with dialkyl acetylenedicarboxylates in the presence of K2CO3-PEG catalytic system at 100 oC was reported. The desired products were obtained in excellent yields (88-92%). Various benzene-1,2-diamin...

A new series of N-(5-Mercapto-1,3,4-thiadiazol-2-yl)-2-phenylacetamide derivatives (3a-3j) were synthesized via an amidation reaction using EDC and HOBt in acetonitrile solvent at room temperature condition. Chemical structures were characterized by 1H NMR, IR and MS spectroscopic methods and related melting points were also determined. The anticancer activity was evaluated using MTT procedure ...

Eosin is one of the original dyes of xanthenes derivatives. It is also one of the main derivatives of fluorescein and has brilliant fluorescence. Eosin disodium salt called "Eosin Y" is the most useful form of this compound. In common procedures, eosin is usually obtained by the action of bromine on fluorescein, which has not good yield and purity degree. In this research, it is prepared by the...

The present study introduces a new technique of homotopy perturbation method for the solution of systems of fractional partial differential equations. The proposed scheme is based on Laplace transform and new homotopy perturbation methods. The fractional derivatives are considered in Caputo sense. To illustrate the ability and reliability of the method some examples are provided. The results ob...