in the present study, theoretical chemical reactivates photo isomerization in cis-retinal as a natural photo switch in vision. dft hybrid functional, b3lyp and, post-hf method, were the theoretical methods applied utilizing g09 software. 6-31g+ (d,p) basis set employed for structural optimizations, and single point computations performed using b3lyp/6-31g+(d,p). the isomers cis molecule retinal...

the enzymatic potential of the cultured plant cells can be employed for bioconversion purposes. plant enzymes are able to catalyze regio- and stereo-specific reactions, and therefore can be applied for the production of desired substances. the biotransformation of foreign substrates with suspension cells of peganum harmala was tested with (±) phenylethyl propionate. the callus cultures of pegan...

We study a monocyclic peptide called cAPB, whose conformations are light switchable due to the covalent integration of an azobenzene dye. Molecular dynamics (MD) simulations using the CHARMM22 force field and its CMAP extension serve us to sample the two distinct conformational ensembles of cAPB, which belong to the cis and trans isomers of the dye, at room temperature. For gaining sufficient s...

Conformational disorder in crystals is found in many molecules that possess a plurality of conformational isomers. Typical examples are linear macromolecules such as polyethylene, polytetrafluoroethylene and trans-1,4-polybutadiene; and small molecules such as paraffins, cycloparaffins, soaps, lipids and many liquid-crystal forming molecules. Conformational motion is often coupled with the coop...

Two possible isomers of some 1,3-diaryl-H-benzo[f]chromene have been studied using density functional theory. Structures of E1 and E2 isomers were optimized at the B3LYP and MP2 levels with different basis sets. The total electronic energies show that E2 isomer is about 3-5 kcal/mol more stable than E1 isomer and this energy difference is attributed to the planarity of heterocyclic ring and mor...

The conformational landscape of the structural isomers acetovanillone (apocynin, AV) and 6-hydroxy-3-methoxyacetophenone (HMAP) has been investigated in a supersonic jet using Fourier transform microwave spectroscopy. Two conformers have been detected in the jet-cooled expansion for each molecule (s-cis and s-trans in AV; s-trans and a-trans for HMAP), differing in the relative orientation of t...

The conformation of the L-iduronate residue in non-sulphated di-, tetra- and hexa-saccharides and their alditol derivatives derived from rooster comb dermatan sulphate was investigated by 400 MHz 1H-n.m.r. spectroscopy. The ratio of conformational isomers is obtained by the average spin-spin coupling constants of a mixture of nearly isoenergetic conformers (1C4, 4C1 and 2S0). The non-reducing t...

5(6)-Carboxy-rhodamine 110 isomers were rapidly synthesized by condensation of 3-aminophenol and trimellitic anhydride using microwave irradiation as heating method. After esterification of the two isomers, separation and hydrolyzation provided target products,5-carboxy-rhodamine 110 and 6-carboxy-rhodamine 110, in high yields. The results shows microwave irradiation can effectively reduce ...

We analyzed the correlation between the conformational strain and the binding kinetics in antigen-antibody interactions. The catalytic antibodies 6D9, 9C10, and 7C8 catalyze the hydrolysis of a nonbioactive chloramphenicol monoester derivative to generate a bioactive chloramphenicol. The crystal structure of 6D9 complexed with a transition-state analog (TSA) suggests that 6D9 binds the substrat...