[reaction: see text] A study of the role of base in the isomerization of manganese-coordinated conjugated alkynyl carbonyls to the corresponding allenyl carbonyls is described. The use of phosphine additives indicates that manganese requires a ligand prior to isomerization with amine bases. A series of amine bases were also examined for their efficacy in this isomerization reaction revealing a ...

The cis<-->trans isomerization reaction has been carried out for 2-naphthol and its hydrogen (H) bonded clusters by infrared (IR) laser in the electronic excited state (S1) in supersonic jets. A specific isomer in the jet was pumped to the X-H stretching vibration in the S1 state, where X refers to C, O, or N atom, by using a stepwise UV-IR excitation, and the dispersed emission spectra of the ...

Accepted on 8 th April 2014 _____________________________________________________________________________ ABSTRACT Z-E isomerization in sunitinib, an important anticancer drug, has been investigated. The influence of light, heat and solvent was studied and the isomerizations were monitored by HPLC. As expected, the extent of Z-E isomerization (conversion of the Z-isomer into the undesired E-iso...

the reaction kinetics of the isomerization 3,4-dichlorobutene-1 to 1,4-dichlorobutene-2 was investigated by using gas-liquid chromatography method in the presence of fe2o3/mgo as solid catalyst in the temperature range 25-55°c. fe2o3/mgo has been prepared by the support saturation method, tested in the isomerization of 3, 4-dichlorobutene-1 into 1, 4-dichlorobutene-2. this catalyst shows a high...

Biological signal transduction by photoactive yellow protein (PYP) in halophilic purple sulfur bacteria is initiated by trans-to-cis isomerization of the p-coumaric acid chromophore (pCa) of PYP. pCa is engaged in two short hydrogen bonds with protein residues E46 and Y42, and it is negatively charged at the phenolate oxygen. We investigated the role in the isomerization process of the E46 shor...

The crystal structure of the interleukin-2 tyrosine kinase Src homology domain (Itk SH2) is described and it is found that unlike in studies of this domain using NMR spectroscopy, cis-trans-prolyl isomerization is not readily detected in the crystal structure. Based on similarities between the Itk SH2 crystal form and the cis form of the Itk SH2 NMR structure, it is concluded that it is likely ...

The cis-trans isomerization of proline serves as a regulatory switch in signaling pathways. We identify the proline isomerase Fpr4, a member of the FK506 binding protein family in Saccharomyces cerevisiae, as an enzyme which binds the amino-terminal tail of histones H3 and H4 and catalyses the isomerization of H3 proline P30 and P38 in vitro. We show that P38 is necessary for methylation of K36...

Industrial process control system due to integration of equipment, existing material and energy recycle streams and their effects are extraordinary importance. The process in terms of safety, product quality and control stability have a challenge when there was defects in a process control system. The isomerization process is gaining importance in the presence of refining context due to upgradi...

An isomerization reaction of a tetra-peptide, Ac-Gly-Asp-Gly-Gly-NHMe → Ac-Gly-isoAsp-Gly-Gly-NHMe, was investigated by DFT calculations. Thirteen water molecules were added to the peptide for simulating proton transfers during the isomerization. As a starting analysis, the number (m) of water molecules participating in ready proton transfers was examined by the use of a small model system, H(3...

We propose a new scheme of the photoactivation and the photobleaching for Dronpa with molecular dynamics method and density functional theory. These processes can be explained by considering cis-trans isomerization in neutral state of chromophore. The proton transfer from anionic to neutral chromophore makes cis-trans isomerization possible via hula-twist rotation process, since the space for c...