Rapid and selective detection of biothiols by novel ruthenium(II) complex-based phosphorescence probes.

Considering the excellent photochemical properties of ruthenium(II) complexes, two new ruthenium(II) complexes, RuL-DNBS and RuL-DNBS, have been developed as phosphorescence probes for detection of biothiols in 100:1 (v/v) Hepes buffer (20 mM, pH = 7.2)/CHCN solution. The response rate was highly improved of these two probes toward biothiols because the steric interactions between 1H-imidazo [4, 5-f] [1,10] phenanthroline group and ortho-2, 4-dinitrobenzensulfonate resulted in a relatively rapid thiol-induced SAr substitution reaction.

The synthesis, characterization and optical properties of novel 2-acyl 6-arylindolizines.

A series of novel 2-acyl-6-aryl substituted indolizine derivatives was synthesized by a novel tandem reaction between 4-acyl-pyrrole-2-carbaldehyde derivatives and ethyl 4-bromo-3-arylbut-2-enoate under mild conditions. The compounds were characterized using IR, (1)H NMR (13)C NMR and HRMS. The crystal structure of 7a was determined using single crystal X-ray crystallography.

The synthesis, characterization and optical properties of novel 5-(3-aryl-1H-pyrazol-5-yl)-2-(3-butyl-1-chloroimidazo[1,5-a]pyridin-7-yl)-1,3,4-oxadiazole.

A series of novel 5-(3-aryl-1H-pyrazol-5-yl)-2-(3-butyl-1-chloroimidazo[1,5-a]- pyridin-7-yl)-1,3,4-oxadiazole derivatives has been synthesized from 3-butyl-1-chloroimidazo[1,5-a]pyridine-7-carboxylic acid and ethyl 3-aryl-1H-pyrazole-5-carboxylate. The compounds were characterized using IR, (1)H NMR, HRMS and UV-vis absorption. The fluorescence spectral characteristics of the compounds in dichloromethane were investigated.

Synthesis, crystal structure, optical properties and antibacterial evaluation of novel imidazo[1, 5-a]pyridine derivatives bearing a hydrazone moiety.

A series of novel imidazo[1,5-a]pyridine-hydrazone derivatives were synthesized and characterized by infrared spectroscopy (IR), 1H NMR, 13C NMR and high resolution mass spectrometer (HRMS). Typically, the spatial structure of compound 3j was determined using X-ray diffraction analysis. The UV-vis absorption and fluorescence spectral characteristics of the compounds in dichloromethane and acetonitrile were investigated.

1-(1-Benzyl-1H-benzimidazol-2-yl)ethanone.

In the title compound, C16H14N2O, the benzimidazole ring system is essentially planar. The planes of the benzene rings make a dihedral angle of 85.92 (8)°.

Ethyl 2,4-dimethyl-pyrido[1,2-a]benz-imidazole-3-carboxyl-ate.

The title compound, C(16)H(16)N(2)O(2), was synthesized using a novel tandem annulation reaction between 1-(1H-benzo[d]imidazol-2-yl)ethanone and ethyl (E)-4-bromo-but-2-enoate under mild conditions. The dihedral angles formed by the mean plane of the five-membered imidazole ring with the dihydro-pyridin and benzene rings are 1.54 (9) and 1.

4-Acetyl-1H-pyrrole-2-carbaldehyde.

The title compound, C(7)H(7)NO(2), was synthesized via a one-pot Vilsmeier-Haack and subsequent Friedel-Crafts reaction. The pyrazole ring makes dihedral angles of 4.50 (9) and 2.

The optical properties, synthesis and characterization of novel 5-aryl-3-benzimidazolyl-1-phenyl-pyrazoline derivatives.

A series of novel 5-aryl-3-benzimidazolyl-1-phenyl-pyrazoline derivatives were synthesized by the reaction of benzimidazolyl chalcone and phenylhydrazine in 41-72% yields. The compounds were characterized using IR, (1)H NMR and HRMS. Absorption and fluorescence spectra were measured in different organic solvent.

3-(4-Bromo-phen-yl)-1-(4-chloro-benz-yl)-1H-pyrazole-5-carbaldehyde.

The title compound, C(17)H(12)BrClN(2)O, was synthesized by oxidation of [3-(4-bromo-phen-yl)-1-(4-chloro-benz-yl)-1H-pyrazol-5-yl]methanol under mild conditions. The pyrazole ring makes dihedral angles of 3.29 (9) and 74.

Synthesis, characterization, optical properties and theoretical studies of novel substituted imidazo[1,5-a]pyridinyl 1,3,4-oxadiazole derivatives.

Novel imidazo[1,5-a]pyridinyl 1,3,4-Oxadiazole derivatives were synthesized and characterised by IR, (1)H NMR and HRMS.UV-vis absorption and fluorescence properties of these compounds in different solutions showed that the maximal emission wavelength was not significantly changed in different solvents; however, maximum absorption wavelength was blue-shifted with the increase of solvent polarity. Absorption λ(max) and emission λ(max) was less correlated with substituent groups on benzene rings.

Ethyl 2-methyl-4-phenyl-pyrido[1,2-a]benzimidazole-3-carboxyl-ate.

The title compound, C(21)H(18)N(2)O(2), was synthesized using a novel tandem annulation reaction between (1H-benzimidazol-2-yl)(phen-yl)methanone and (E)-ethyl 4-bromo-but-2-enoate under mild conditions. The dihedral angles between the mean planes of the five-membered imidazole ring and the pyridine, benzene and phenyl rings are 0.45 (6), 1.

Ethyl 1-benzyl-3-(4-bromo-phen-yl)-1H-pyrazole-5-carboxyl-ate.

In the title compound, C(19)H(17)BrN(2)O(2), the pyrazole ring makes dihedral angles of 88.00 (16) and 5.78 (13)° with the phenyl and bromo-phenyl rings, respectively.

Ethyl 1-(4-chloro-benz-yl)-3-(4-fluoro-phen-yl)-1H-pyrazole-5-carboxyl-ate.

In the title compound, C(19)H(16)ClFN(2)O(2), the pyrazole ring makes dihedral angles of 5.15 (6) and 77.72 (6)°, with the fluoro-phenyl and chloro-phenyl rings, respectively.

Ethyl 6-methyl-2-p-tolyl-pyrazolo[1,5-a]pyridine-5-carboxyl-ate.

In the title mol-ecule, C(18)H(18)N(2)O(2), the bicyclic ring system and the benzene ring form a dihedral angle of 13.45 (3)°. In the crystal structure, weak inter-molecular C-H⋯O hydrogen bonds link mol-ecules into chains propagated along [201].

Ethyl 5-(ethoxy-carbon-yl)-3-(4-methoxy-phen-yl)-1H-pyrazole-1-acetate.

In the title compound, C(17)H(20)N(2)O(5), all bond lengths and angles show normal values. The dihedral angle between the pyrazole ring and the benzene ring is 6.98 (11)°.

1-(2-Hydr-oxy-5-methoxy-phen-yl)ethan-1-one N-[(E)-1-(2-hydr-oxy-5-methoxy-phen-yl)ethyl-idene]hydrazone.

In the title mol-ecule, C(18)H(20)N(2)O(4), which resides on a crystallographic centre of inversion (at the centre of the N-N bond), all non-H atoms apart from the meth-oxy substituent are approximately coplanar. The structure displays intra-molecular O-H⋯N hydrogen bonding.