As potential new analgesics, the corresponding 4-hydroxy-2,2-dioxo-1H-2λ⁶,1-benzothiazine-3-carboxanilides have been obtained by amidation of ethyl 4-hydroxy-2,2-dioxo-1H-2λ⁶,1-benzothiazine-3-carboxylate with aniline and its halogenated analogsin boiling dry xylene. The peculiarities of the mass and nuclear magnetic resonance (¹Н and 13С) spectra of the synthesized compounds are discussed. Usi...

A series of long-chain methyl esters with vicinal oxo groups (1,2-diones; 1,2-diketones) were synthesized by potassium permanganate-based oxidation of methyl esters of mono-unsaturated fatty acids. The presence of two additional carbonyl groups may facilitate the synthesis of other derivatives. The starting materials were selected in such a fashion to give the 1,2-dioxo moiety in consecutive po...

In the title mol-ecule, C(35)H(22)BrNO(2), the four-membered ring of the β-lactam unit is nearly planar [maximum deviation = 0.003 (3) Å] and makes dihedral angles of 87.07 (15), 59.80 (16) and 20.81 (19)°, respectively, with the xanthene system, the anthracene system and the bromo-substituted benzene ring. The mol-ecular conformation is stabilized by weak intra-molecular C-H⋯O and C-H⋯N hydrog...

An enhanced fluorescent emission of the dye Rhodamine 800 in the Near-IR is observed in the presence of other xanthene dye molecules (RhX) when they are hosted in different matrices due to the formation of a new type of fluorescent J-heteroaggregates. This enhanced emission of the acceptor occurs despite the low spectral overlapping and the low quantum yield of Rh800.

In the title mol-ecule, C(30)H(36)N(4)O(3), the dihedral angle between the planes of the xanthene and spiro-lactam rings systems is 88.69 (4)°. Both C atoms of one of the ethyl groups are disordered over two sites with occupancies 0.72 (2)/0.28 (2). The conformation of the mol-ecule may be influenced by two intra-molecular hydrogen bonds.

A novel fast, convenient and inexpensive synthesis of 1',3'-dioxo-1',3'-dihydrospiro[cyclopropane-1,2'-indene]-2,2,3,3-tetracarbonitrile and dimethyl 2,3-dicyano-1',3'-dioxo-1',3'-dihydrospiro[cyclopropane-1,2'-indene]-2,3-dicarboxylate is reported. These compounds undergo double carbanion cleavage under the action of alcohols resulting in the formation of stable salts, containing new allylic-t...

poly(4-vinylpyridine)-supported copper iodide nanoparticles is reported as a new, green and recyclable catalyst for the synthesis of aryl-14h-dibenzo [a-o] xanthenes under solvent-free conditions. this catalyst can be recovered by simple filtration and recycled up to 8 consecutive runs without any loss of their efficiency.

Scintillation properties of 14-phenyl-14H-dibenzo[a,j]xanthenes (called material A) is studied. Cyclohexan is used as a solvent, whilst Anthracene and Naphthalene are used as secondary solutes. The response of the scintillator to low energy Gamma-rays is detectable. Our study shows that the addition of material A (0.01 mol L ) to the solution of Anthracene-Naphthalene-Cyclohexan, improves the d...

Humulones and iso-humulones are potent natural antioxidants found in beer. In this study, density functional theory (DFT) method was applied for elucidating the structure-antioxidant activity relationship molecular mechanism of antioxidant eight bioactive humulones previously identified different beer samples: isoxanthohumol, (R)- (S)-adhumulone, cis- trans-iso-adhumulone, trans-iso-n-humulone,...

Supported WOx/SiO2 catalysts were investigated for propylene metathesis as a function of tungsten oxide loading and temperature. The catalysts were synthesized by incipient-wetness impregnation of an aqueous ammonium metatungstate solution onto the silica support and calcined at elevated temperatures to form the supported tungsten oxide phase. In situ Raman spectroscopy under dehydrated conditi...