Search

The structural analysis of khellinone and visnaginone indicated the planarity of the benzo[b]furan ring system. The oxygen or carbon atoms of the substituents, - OH, - OCH, and - C(=O)CH, are nearly coplanar with the aromatic ring. The molecular conformation is stabilized by the intramolecular O-H···O hydrogen bond formed between the ortho-substituted hydroxyl and acetyl groups. The intermolecular contacts present in the crystal structure are the C-H···O and C-H···π interactions and the π··· π stacking. The energy surface for the internal rotation about the C-O/C bonds in the khellinone and visnaginone molecules has been explored by quantum-chemical calculations. The density functional theory (DFT) methods yielded three stable conformers of khellinone and two of visnaginone obtained by a rotation of the methoxy group about the C4- OCH bond. The most stable conformation in the gas phase is consistent with the stereochemistry of the molecules adopted in the solid. The secondary minima conformers have energies higher by 0.3-1.8 kcal/mol. The energy of the intramolecular O-H···O interactions, present in the molecular structure of all stable conformers, is around 18 kcal/mol at the DFT level. A complete and reliable assignment of the bands in the IR and Raman spectra of both compounds has been performed. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The selected derivatives of the 2- and 3-benzo[ b]furancarboxylic acids were synthesized and their structures were studied using the X-ray crystallography and the computational methods. The monocarboxylic acids ( 1- 3) crystallize as dimers stabilized by the O-H···O intermolecular hydrogen bonds. Moreover, intramolecular hydrogen bonds are formed between the OH and C(=O)CH groups, substituted to the aromatic ring ( 2- 4). In the crystal structures of 1- 4, weak C-H···O, C-H···π, and C-H···Br interactions stabilize the three-dimensional packing of molecules. The crystalline sodium complex of 1 has the stoichiometry [ Na· 1A· 1B]· 1C, thus, the asymmetric unit contains three different moieties of 1. In this complex, the Na cation is hexacoordinated having a strongly distorted tetragonal bipyramidal polyhedron. For each molecule 1- 4, several conformers were obtained in the gas phase. It was achieved by the rotations of substituents [COOR and/or C(=O)CH, where R = H, CH] with respect to the rigid benzo[ b]furan system. As indicated by the quantum-chemical calculations, the solid-state conformers for 3 and 4 (3-benzo[ b]furancarboxylic acid derivatives) are the most stable ones. In contrast, the solid-state conformers of the 2-benzo[ b]furancarboxylic acid derivatives ( 1, 2) have the energies higher than the lowest energy conformer by 1.23 and 0.69 kcal/mol, respectively. It seems that intermolecular contacts in the crystal influence on the orientation of substituents, and the conformers observed in the sodium complex of 1 provide evidence of such flexibility. Graphical Abstract: Hirshfeld surface for a pair of molecules 2A/2B (bromo-derivative).[MediaObject not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The preparation of twelve aminoalkanol derivatives of 2,3-dihydro-5 H-[1,4]dithiino[2,3- c]pyrrole-5,7(6 H)-dione was described. Newly obtained compounds, as well as their propyl and butyl analogues, were evaluated in vitro against selected viruses. Selected derivatives were tested for their antibacterial and antifungal activity. Compounds 3h, 3j, 4b and 5a- d showed moderate to significant protections against CVB-2, HSV-1 and YFV viruses. The molecular structures of 4a, 5c and 5g were determined by an X-ray analysis. [ABSTRACT FROM AUTHOR]

A series of thiourea derivatives of 4-azatricyclo[5.2.2.02,6]undec-8-ene-3,5-dione were synthesized. The compounds were investigated for antibacterial activity, including Gram-positive cocci, Gram-negative rods, and antifungal activity. Compounds 1b, 2b, 4b showed significant inhibition against Gram-positive cocci. Research was carried out over 10 standard strains and 20 hospital strains. Synthesized compounds were evaluated for their cytotoxicity and anti-HIV-1 activity in MT-4 cells. [ABSTRACT FROM AUTHOR]

A series of 13 new ether-linked derivatives of 2,2-dimethyl-2,3-dihydro-7-benzo[b]furanol have been designed and synthesized. Ten of them were evaluated for their potential antimicrobial activity against some Gram-positive and Gram-Negative bacteria and fungi of the Candida species. [ABSTRACT FROM AUTHOR]

The synthesis and pharmacological activity of 4-[2-hydroxy-3-(4-phenyl-piperazin-1-yl)-propoxy]-4-aza-tricyclo[5.2.1.02,6]dec-8-ene-3,5-dione is described. The structure of the compound was confirmed by elemental analysis, 1H nuclear magnetic resonance (NMR), 13C NMR, mass spectra, and X-ray crystallography. The compound exhibited significant affinity to both 5-HT1A and 5-HT2A receptors, similarly to aripiprazole, which is an atypical antipsychotic drug. [ABSTRACT FROM AUTHOR]