It is well known that singlet state aromaticity quite insensitive to substituent effects, in the case of monosubstitution. In this work, we use density functional theory (DFT) calculations examine sensitivity triplet effects. For purpose, chose antiaromatic cyclopentadienyl cation, antiaromaticity which reverses aromaticity, conforming Baird’s rule. The extent (anti)aromaticity was evaluated by...

The electronic effects of Rh(II)-mediated carbenoid intramolecular C-H insertion have been intensively investigated. The chemo-, regio-, and stereoselectivity of the reaction have been observed to be affected by the electrophilicity of the carbene-Rh intermediate, the substituents on the carbon at which the C-H insertion occurs, and steric and conformational factors.1 It has been well documente...

Hetero-Diels-Alder reaction with sulfines generated in situ from methylsulfones 5a-e substituted in α-position with a phosphonyl, carboxyl, carboxyoxazolidinyl, pyridyl, or a quinolyl substituent, respectively, led to new highly functionalized thiopyrans cycloadducts. When in the substrates (i.e. 5a-c) the sulfonyl group and the second substituent on the methylene carbon have comparable electro...

New derivatives of 2-[2-(2-Chlorophenoxy)phenyl]-1,3,4-oxadiazole as candidates for agonistic effect on benzodiazepine receptors were synthesized. Conformational analysis and superimposition of energy minima conformers of the novel compounds on estazolam, a known benzodiazepine agonist, revealed that the main proposed benzodiazepine pharmacophores were well matched. In pharmacological evaluatio...

A theoretical study on the effects of a moderate amount of sulfur when used as substituent impurity in place of oxygen in zinc oxide at its crystal form using Density Functional Theory (DFT). S-substituent amounts in percent go from 0.1% up to 1.0% and we analyze modifications in the crystal properties such as lattice characteristics, total energy, and gap energy. Lattice parameter c increased ...