The collective electronic oscillators (CEO) approach based on the TDHF approximation is combined with INDO/S, MNDO, AM1, and PM3 semiempirical Hamiltonians. This technique is applied to compute and analyze the electronic structure of acceptor-substituted oligomers and conjugated polymers. Calculated excited-state energies and oscillator strengths agree well with the experimental data and with e...

New C,C-linked bipyrazole 1,1’-di(4-aminophenyl)-5,5’-diisopropyl-3,3’-bipyrazole (2) has been synthesized and characterized. Theoretical calculations have been carried out on target 2 and literature 1 C,C-linked bipyrazoles to compare with reported results. All calculations were carried out with the AM1 level of theory using the GAUSSIAN 03. The nature of substituent attached to the pyrazolic ...

13C NMR spectra of molecules containing one or two benzene rings linked with CH=CH2, CH=CH (transor cis-), C C and CH=N groups revealed the existence of long range deuterium isotope effects on 13C chemical shifts. It was found that deuterium isotope effects over six bonds (6D) are related to the conformation of investigated molecules. Molecular torsional angles were calculated by ab initio HF/6...

This paper presents the synthesis, the structural determination and the sensing capabilities toward Volatile Organic Compounds (VOCs) of a new class of fluorescent indolizine-cyclodextrin sensors. Two different pathways, both involving bipyridinium ylides and 6-amino-b-cyclodextrin, have been used to carry out the synthesis of these sensors. The macrocycle structures were dominantly established...

The COnductor-like Screening MOdel of solvent-solute interactions of Klamt and Schüürmann, COSMO, at the semiempirical AM1 level of MO calculations, augmented by limited singles and doubles configuration interaction, proves useful for the study of solvent induced shifts of fluorescence spectra. Optimization of geometry of ground S0 and excited S1 states for each solvent separately provides esti...

Thermostable glycoprotein amyloid bioemulsifier BE-AM1 was reported from Solibacillus silvestris AM1. S. could produce better in 1% inoculum size and 18h age. The production by AM1 has been seen to be unaffected amending the growth medium (Zobel Marine medium) with Carbon Nitrogen sources. effects of 16 nutrient factors (from ZM were analyzed statistically one factor at a time, Plackett-Burman ...

New 1,2-di-substituted carbocyclic nucleosides with 6-chloropurine, adenine and hypoxanthine bases were synthesized by construction of purine on the primary amino group of (+/-)-trans-2-aminocyclopentylmethanol. AM1 calculations showed close correspondence between the positions of the heteroatoms in the adenine derivative and dideoxyadenosine. The most active of the new compounds in antiviral a...

Semi-empirical (AM1) electronic structure calculations are reported on a pH-switchable [2] rotaxane whose synthesis was reported in [Angew. Chem. Int. Ed., 36 (1997) 1904]. The [2] rotaxane possesses two cationic binding sites, with different affinities toward dibenzo [24] crown-8 (the ring component of the [2] rotaxane) depending upon the pH of the system. The computational results capture thi...

Hydration free energy calculations have become important tests of force fields. Alchemical free energy calculations based on molecular dynamics simulations provide a rigorous way to calculate these free energies for a particular force field, given sufficient sampling. Here, we report results of alchemical hydration free energy calculations for the set of small molecules comprising the 2011 Stat...

BACKGROUND Helicobacter pylori, colonize in stomach of ~50% of the world population. cag pathogenicity Island of H. pylori is one of the important virulent factors that attributed to gastric inflammation. Coinfection with H. pylori strain with different genetic makeup alters the degree of pathogenicity and susceptibility towards antibiotics. The present study investigates host immunomodulatory ...