In the monomeric title complex, [Li(C4H3N2O2)(H2O)3], the Li(+) cation is coordinated by a pyrazole N atom and three water mol-ecules in a distorted tetra-hedral geometry. The carboxyl-ate group is deprotonated. The complex mol-ecules are involved in O-H⋯O and N-H⋯O hydrogen bonding, forming layers stacked along the b axis.

The N-nitroso-derivative of melatonin, NOM (1-nitrosomelatonin), which has been demonstrated to be a NO* [oxidonitrogen*] donor in buffered solutions, is a new potential drug particularly in neurological diseases. The advantage of NOM, a very lipophilic drug, is its ability to release both melatonin and NO*, an easily diffusible free radical. In order to evaluate the distribution and the pharma...

Duodenal Fe2+ uptake is essential to body Fe2+ homeostasis, but the interaction of metals with the uptake process remains unclear. The present study compared the effects of four essential trace metals (Mn2+, Zn2+, Co2+ and Ni2+) with two toxic metals (Pb2+ and Cd2+) on Fe2+ uptake across the brush border membrane of villus-attached duodenal enterocytes. Everted rat duodenum was exposed to buffe...

Phosphoenolpyruvate carboxykinase from rat liver cytosol is activated by Fe2+ ions in either direction of catalysis. Preincubation of the purified enzyme with Fe2+ ions causes a time-dependent irreversible loss of activity; this is not seen with unpurified enzyme. Purified enzyme can be protected from inactivation by Fe2+ ions by partially purified protein fractions from liver (ferroactivator f...

Life originated in an anoxic, Fe2+-rich environment. We hypothesize that on early Earth, Fe2+ was a ubiquitous cofactor for nucleic acids, with roles in RNA folding and catalysis as well as in processing of nucleic acids by protein enzymes. In this model, Mg2+ replaced Fe2+ as the primary cofactor for nucleic acids in parallel with known metal substitutions of metalloproteins, driven by the Gre...

Active site mimics of [FeFe]-hydrogenase are shown to be bidirectional catalysts, producing H2 upon treatment with protons and reducing equivalents. This reactivity complements the previously reported oxidation of H2 by these same catalysts in the presence of oxidants. The complex Fe2(adtBn)(CO)3(dppv)(PFc*Et2 ) ([1]0; adtBn = (SCH2)2NBn, dppv = cis-1,2-bis(diphenylphosphino)ethylene, PFc*Et2 =...

Pressure-induced structural changes in di-iron nonacarbonyl [Fe2(CO)9] were examined by in situ Raman spectroscopy with the aid of a diamond anvil cell. Our results indicate that Fe2(CO)9 undergoes a pressure-induced phase transformation at about 0.9 GPa. Upon further compression, another structural transformation is identified at 7 GPa. In the low-pressure phase below 0.9 GPa, the π back-bondi...

A low-coordinate iron(ii) complex (CztBu(PztBu)2)Fe[N(SiMe3)2], 1 bearing an NNN-pincer ligand was prepared and fully characterized. Intramolecular C-H activation on the 5-position of a pyrazole at elevated temperatures was observed. Complex 1 was found to be an efficient and chemoselective pre-catalyst for the hydrosilylation of organo carbonyl substrates.

Microstructure-sensitive design is performed using a newly developed Multiscale Complex Step Method. Algorithmic implementation of the complex-step method is based on conventional multiscale Taylor or FE2 direct model, with the difference being that the microstructural deformation gradient is modeled as a complex number with a small imaginary component. We introduce methods to calculate derivat...

densely functionalized 3-(4-chlorophenyl)-5-(3-hydroxy-4-etoxyphenyl)-4,5-dihydro-1h-pyrazole-1-carboxamide was  synthesized in an expedient manner through specification and transamidation  respectively, of ester-functionalized pyrazoles. this synthetic protocol allowed for three diversifying steps in which appendages on the pyrazole scaffold were adjusted to optimize inhibition of protein kina...