Simple energy calculations show that there is a significant interaction between a hydrogen bond donor (like the greater than NH group) and the centre of a benzene ring, which acts as a hydrogen bond acceptor. This interaction, which is about half as strong as a normal hydrogen bond, contributes approximately 3 kcal/mol (1 cal = 4.184 J) of stabilizing enthalpy and is expected to play a signific...

The influence of cation-π interactions on the strength and nature of intramolecular O...H hydrogen bond has been investigated by quantum chemical calculations in orthohydroxy benzaldehyde (HBA) compound. Ab initio calculations have been performed at MP2/6-311++G** level of theory. Vibrational frequencies and physical properties such as chemical potential and chemical hardness of these compounds...

            We report herein the synthesis of ¾ substituted benzene sulfonamides linked via phenyl ring to a benzothiazole moiety. The title compounds in the two series namely N-(4-(benzothiazole-2-yl) phenyl) 4- substituted benzene sulfonamides and N-(4-(benzothiazole-2-yl) phenyl) 3- substituted benzene sulfonamides were synthesized by condensing 2-(3/4-aminophenyl) benzothiazole with various...

Molecular dynamic simulation is a powerful method that monitors all variations in the atomic level in explicit solvent. By this method we can calculate many chemical and biochemical properties of large scale biological systems. In this work all-atom molecular dynamics simulation of polyalanine (PA) was investigated in the presence of 0.224, 0.448, 0.673, 0.897 and 1.122 M of guanidinium chlorid...

The semiquantal time-dependent Hartree (SQTDH) theory is applied to the coupled Morse and modified Lippincott-Schroeder (LS) model potentials of hydrogen bond. The structural correlation between the heavy atoms distance and the proton position, the geometric isotope effect, the energy of hydrogen bond formation, and the proton vibrational frequency shift are examined in a broad range of structu...

We report results of molecular dynamics (MD) simulations characterising the hydrogen bonding in mixtures of two different protic ionic liquids sharing the same cation: triethylammonium-methylsulfonate (TEAMS) and triethylammonium-triflate (TEATF). The triethylammonium-cation acts as a hydrogen-bond donor, being able to donate a single hydrogen-bond. Both, the methylsulfonate- and the triflate-a...