A highly diastereoselective, visible-light-induced [3 + 2] cycloaddition between N-sulfonyl cyclopropylamines and electron-deficient olefins is reported. The reactions proceed via the oxidation of a sulfonamide aza-anion by an organic photocatalyst to generate nitrogen-centered radical. Strain-induced ring opening intermolecular addition olefin intermediate carbon-centered radical that reduced ...

qct calculations were performed to study the behavior of energized nh2oh formed by association collision of nh2 radical with oh radical. a potential energy surface that describes the behavior of the title reaction has been constructed by interpolation of ab initio data. h2o, hon, hno, nh3, o, h2no, cis or trans-honh, and h products and two vibrationally energized nh2oh and nh3o adducts were obs...

Femtosecond visible pump-IR probe studies of Cp2W2(CO)6 in P(OMe)3 and CH2Cl2 have allowed direct observation of a 19-electron intermediate and of disproportionation into CpW(CO)3- and CpW(CO)3P(OMe)3+ on the ultrafast time scale. A new disproportionation mechanism involving in-cage electron transfer between a 19-electron intermediate and a 17-electron radical has been proposed.

The location of the Trp radical and the catalytic function of the [Fe(IV)═O Trp₁₉₁(•+)] intermediate in cytochrome c peroxidase (CcP) are well-established; however, the unambiguous identification of the site(s) for the formation of tyrosyl radical(s) and their possible biological roles remain elusive. We have now performed a systematic investigation of the location and reactivity of the Tyr rad...

The kinetics of the oxidation of imipramine and desipramine using cerium(IV) complexes were studied in the presence of a large excess of azepine derivative (TCA) in acidic sulfate media using UV-Vis spectroscopy. The reaction proceeds via dibenzoazepine radical formation, identified by EPR measurements. The kinetics of the first degradation step were studied independently of the further slower ...

the smooth muscle of the gastrointestinal (GI) tract of dog and is potentially useful as a GI prokinetic agent. In an effort to extend the SARof the motilides, we decided to determine the effect of C-12 deoxygenation of 2 on both antibacterial and prokinetic activities. The deoxy congener with the natural (R) configuration at C-12 4 is synthetically accessible3) from erythromycin B 3, but in or...

Ultrafast electron diffraction is a unique method for the studies of structural changes of complex molecular systems. In this contribution, we report direct ultrafast electron diffraction study of the evolution of short-lived intermediates in the course of a chemical change. Specifically, we observe the transient intermediate in the elimination reaction of 1,2-diiodotetrafluoroethane (C2F4I2) t...

INTRODUCTION Extended pelvic lymph node dissection (ePLND) is advised to complement radical prostatectomy (RP) in intermediate and high risk prostate cancer patients. AIM To assess the risk of nodal involvement in patients subjected to laparoscopic radical prostatectomy and to characterize the group of patients with lymph node (LN) metastases. MATERIAL AND METHODS Data of patients subjected...

Glutaredoxin (GRx, thioltransferase) is implicated in cellular redox regulation, and it is known for specific and efficient catalysis of reduction of protein-S-S-glutathione-mixed disulfides (protein-SSG) because of its remarkably low thiol pK(a) ( approximately 3.5) and its ability to stabilize a catalytic S-glutathionyl intermediate (GRx-SSG). These unique properties suggested that GRx might ...