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A series of chromeno[4,3- d]isoxazolo[5,4- b]pyridin-6-one derivatives were easily and efficiently synthesized by the reaction of 3-acyl-2 H-chromen-2-ones with isoxazol-5-amine in . Some synthesized compounds were evaluated for their antiproliferative properties in vitro against cancer cells, and these compounds were found to have some activities. [ABSTRACT FROM AUTHOR]

A facile and efficient for the preparation of indeno[1,2- b]indole derivatives via three-component domino reaction of ninhydrin, enaminones, and malononitrile catalyzed by L-proline is described. In this reaction, two rings and four bonds were formed by one-pot. [ABSTRACT FROM AUTHOR]

An efficient, convenient Cu-catalyzed formation of chromeno[4,3- c]pyrazol-4(1 H)-ones is reported. In this atom economic process, readily available 3-acylcoumarin hydrazone is oxidative cyclized by direct C-N bond formation. Air has been successfully used as an oxidant, which has important economic and environmental advantages. A broad scope of 3-acylcoumarin hydrazones can be utilized in this process. [ABSTRACT FROM AUTHOR]

A improved and efficient procedure for the synthesis of pyrrolo[2,3,4- kl]acridin-1-one derivatives via the reaction of isatin and enaminone catalyzed by ceric ammonium nitrate under ultrasonic condition has been developed. Compared with the conventional methods, the remarkable advantages of this method are mild reaction conditions, operational simplicity, higher yield, and shorter reaction times. [ABSTRACT FROM AUTHOR]

A series of 5-arylisoxazole and 5-aryl-1 H-pyrazole derivatives was synthesized by the reaction of 3-(dimethylamino)-1-arylprop-2-en-1-one with hydroxylamine hydrochloride or hydrazine hydrate under ultrasound irradiation without using any catalyst. This method has the advantages of easier work-up, mild reaction condition, high yields, shorter reaction time, and environmentally benign procedure. [ABSTRACT FROM AUTHOR]

A simple and efficient synthesis of pyrrolo[2,3,4- kl]acridine-1-one derivatives via the cascade reaction of isatins with enaminones catalyzed by silica sulfuric acid (SSA) has been established. In this reactions, SSA shows a highly catalytic nature: easy to handle procedure, short reaction time, recycle exploitation, insensitivity to air and moisture, and excellent isolated yields. The catalyst could be recycled at least five times. [ABSTRACT FROM AUTHOR]

A series of chromeno[4,3- d]pyrazolo[3,4- b]pyridin-6(3 H)-one derivatives was easily and efficiently synthesized by the reaction of 2 H-chromen-2-ones with pyrazol-5-amines catalyzed by CuCl2⋅2H2O in ethanol. This protocol has the advantages of mild reaction conditions, easy work-up, and high yields. These compounds were showed to have high fluorescence quantum yields, which mentioned their value as luminescence or fluorescence probe. [ABSTRACT FROM AUTHOR]

New crown ether carrying two fluorionophores of cis-dibenzothiazolyldibenzo-24-crown-8 was synthesized from cis-diformyldibenzo-24-crown-8 and 2-aminobenzenethiol. The binding behavior and the optical properties of the crown ether were examined through UV-visible spectroscopy and fluorescence spectroscopy. When complexed with Na+, K+, Rb+, and Cs+ ions, it led to intramolecular charge transfer and caused the changes of the fluorescence spectra. The protonation of the crown ether was also studied. With protonation using CF3COOH, the absorption bands and the fluorescence spectroscopy changed, the maximal fluorescence wavelengths red shifted and the fluorescence intensity with the maximum at 433 nm enhanced strongly. J. Heterocyclic Chem., (2011). [ABSTRACT FROM AUTHOR]