Efficient Photooxidation of Aryl(hetaryl)pyrazolines by Benzoquinone.

Photooxidation of aryl(hetaryl)pyrazolines in the presence of benzoquinone has been studied in organic solvents. This reaction occurs at high rate to provide the corresponding pyrazole in a good yield. The effects of the solvent, pyrazoline structure and oxygen provide definite information on the reaction pathway.

On the Mechanism of Photodehydrogenation of Aryl(hetaryl)pyrazolines in the Presence of Perchloroalkanes.

New (1,5-diaryl-3-pyrazolinyl)coumarins have been synthesized. The compounds do not undergo keto-enol tautomeric transformations with changes in the solvent. (1,5-Diaryl-3-pyrazolinyl)coumarins provide dehydrogenation reaction under irradiation in the presence of perchloroalkanes and manifest themselves as effective photogenerators of acidity.

NIR-fluorescent coumarin-fused BODIPY dyes with large Stokes shifts.

A series of novel non-symmetrical coumarin-fused BODIPY dyes were synthesised. Their absorption and emission properties are strongly influenced by substitution in the coumarin moiety. Diethylamino-substituted dyes showed near-IR emission with large Stokes shifts (up to 144 nm) and good fluorescence quantum yields.

The first series of 4,11-bis[(2-aminoethyl)amino]anthra[2,3-b]furan-5,10-diones: Synthesis and anti-proliferative characteristics.

We developed the synthesis of a series of furan-fused tetracyclic analogues of the antitumor agent ametantrone. The reactions included nucleophilic substitution of propoxy groups in 4,11-dipropoxyanthra[2,3-b]furan-5,10-diones with ethylenediamines, producing the derivatives of 4,11-diaminoanthra[2,3-b]furan-5,10-dione in good yields. Studies of anti-proliferative activity on a panel of mammalian tumor cell lines demonstrated that anthra[2,3-b]furan-5,10-diones were the most potent derivatives among heteroarene-fused ametantrone analogues with one heteroatom.

Discovery of 3-acetyl-4-hydroxy-2-pyranone derivatives and their difluoridoborate complexes as a novel class of HIV-1 integrase inhibitors.

HIV-1 integrase (IN) has emerged as an important therapeutic target for anti-HIV drug development. Its uniqueness to the virus and its critical role in the viral life cycle makes IN suitable for selective inhibition. The recent approval of Raltegravir (MK-0518) has created a surge in interest and great optimism in the field.

Coumarinyl(thienyl)thiazoles: novel photochromes with modulated fluorescence.

Novel photochromic 5-(3'-coumarinyl)-4-(3''-thienyl)thiazoles have been synthesized. These compounds display intensive fluorescence emission in the open form A, which is modulated by light. Fluorescence intensity decreases significantly upon irradiation of A with UV-light (lambda<400 nm) due to formation of the cyclic form B.

New synthetic routes to furocoumarins and their analogs: a review.

Many furocoumarins and their analogs possess a prominent photobiological activity. Some of them are successfully used as drugs in phototherapy of skin diseases. Fries rearrangement of acyloxyheteroarenes, condensation of acylhydroxyheteroarenes with alpha-carbonyl compounds under base catalysis and transformations of dihydrofurocoumarinones are new trends in synthesis of furocoumarins and their analogs.