Bis(2-meth-oxy-benzyl-ammonium) di-aqua-bis-(di-hydrogen diphosphato-κ(2) O,O')cobaltate(II) dihydrate.

The title compound, (C8H12NO)2[Co(H2P2O7)2(H2O)2]·2H2O, crystallizes isotypically with its Mn(II) analogue. It consists of alternating layers of organic cations and inorganic complex anions, extending parallel to (100). The complex cobaltate(II) anion exhibits -1 symmetry. Its Co(2+) atom has an octa-hedral coordination sphere, defined by two water mol-ecules in apical positions and two H2P2O7 (2-) ligands in equatorial positions. The cohesion between inorganic and organic layers is accomplished by a set of O-H⋯O and N-H⋯O hydrogen bonds involving the organic cation, the inorganic anion and the remaining lattice water mol-ecules.

Bis(2,6-di-methyl-anilinium) di-aqua-bis-(di-hydrogen diphosphato-κ(2) O,O')cobaltate(II).

In the title compound, (C8H12N)2[Co(H2P2O7)2(H2O)2], the Co(2+) ion lies on a crystallographic inversion centre and adopts a slightly distorted octa-hedral CoO6 coordination geometry arising from two chelating diphosphate [H2P2O7](2-) ligands and two trans water mol-ecules. In the crystal, the components are linked by O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds and weak aromatic π-π stacking [shortest centroid-centroid separation = 3.778 (2) Å] inter-actions. (001) layers of alternating organic cations and complex inorganic anions are apparent.

Highlights in TMPRSS2 inhibition mechanism with guanidine derivatives approved drugs for COVID-19 treatment.

Transmembrane protease serine 2 (TMPRSS2) has been identified as a critical key for the entry of coronaviruses into human cells by cleaving and activating the spike protein of SARS-CoV-2. To block the TMPRSS2 function, 18 approved drugs, containing the guanidine group were tested against TMPRSS2's ectodomain (7MEQ). Among these drugs, Famotidine, Argatroban, Guanadrel and Guanethidine strongly binds with TMPRSS2 S1 pocket with estimated Fullfitness energies of -1847.12, -1630.87, -1605.81 and -1600.52 kcal/mol, respectively. A significant number of non-covalent interactions such as hydrogen bonding, hydrophobic and electrostatic interactions were detected in protein-ligand complexes. In addition, the ADMET analysis revealed a perfect concurrence with the aptitude of these drugs to be developed as an anti-SARS-CoV-2 therapeutics. Further, MD simulation and binding free energy calculations were performed to evaluate the dynamic behavior and stability of protein-ligand complexes. The results obtained herein highlight the enhanced stability and good binding affinities of the Argatroban and Famotidine towards the target protein, hence might act as new scaffolds for TMPRSS2 inhibition.Communicated by Ramaswamy H. Sarma.

Autonomic and Cardiac Repolarization Lability in Long QT Syndrome Patients.

OBJECTIVE: Long QT-Syndrome (LQTS) patients are at risk of arrhythmias and seizures. We investigated whether autonomic and cardiac repolarization measures differed based on LQTS genotypes, and in LQTS patients with vs. without arrhythmias and seizures. METHODS: We used 24-h ECGs from LQTS1 (n = 87), LQTS2 (n = 50), and LQTS genotype negative patients (LQTS(-), n = 16). Patients were stratified by LQTS genotype, and arrhythmias/seizures. Heart rate variability (HRV) and QT variability index (QTVI) measures were compared between groups during specific physiological states (minimum, middle, & maximum sympathovagal balance, LF/HF). Results were further tested using logistic regression for each ECG measure, and all HRV measures in a single multivariate model. RESULTS: Across multiple physiological states, total autonomic (SDNN) and vagal (RMSSD, pNN50) function were lower and repolarization dynamics (QTVI) were elevated in LQTS(+), LQTS1, and LQTS2, compared to LQTS(-). Many measures remained significant in the regression models. Multivariate modeling demonstrated that SDNN, RMSSD, and pNN50 were independent markers of LQTS(+) vs. LQTS(-), and SDNN and pNN50 were markers for LQTS1 vs. LQTS(-). During sympathovagal balance (middle LF/HF), RMSSD and pNN50 distinguished LQTS1 vs. LQTS2. LQTS1 patients with arrhythmias had lower total (SDNN) and vagal (RMSSD and pNN50) autonomic function, and SDNN remained significant in the models. In contrast, ECG measures did not differ in LQTS2 patients with vs. without arrhythmias, and LQTS1 and LQTS2 with vs. without seizures. CONCLUSION: Autonomic (HRV) and cardiac repolarization (QTVI) ECG measures differ based on LQTS genotype and history of arrhythmias in LQTS1. SDNN, RMSSD, and pNN50 were each independent markers for LQTS genotype.

Bis(2-methyl-anilinium) diaqua-bis[dihydrogendiphosphato(2-)]cobaltate(II).

In the title cobalt(II) complex with 2-methyl-anilinium and diphosphate, (C(7)H(10)N)(2)[Co(H(2)P(2)O(7))(2)(H(2)O)(2)], a three-dimensional network is built up from anionic layers of [Co(H(2)P(2)O(7))(2)(H(2)O)(2)](2-) units and 2-methyl-anilinium cations located between these layers. The dihydrogendiphosphate groups present a bent eclipsed conformation, while the Co(2+) ions lie on inversion centers. An intricate network of O-H⋯O and N-H⋯O hydrogen bonds is established between the different components, assuring the cohesion of the network with other inter-actions, being of electrostatic and van der Waals nature.

Pr3+ doping at the A-site of La0.67Ba0.33MnO3 nanocrystalline material: assessment of the relationship between structural and physical properties and Bean-Rodbell model simulation of disorder effects.

Bulk nanocrystalline samples of (La1-x Pr x )0.67Ba0.33MnO3 (0.075 ≤ x ≤ 0.30) manganites with a fixed carrier concentration are prepared by the sol-gel based Pechini method. Rietveld refinement of the X-ray diffraction patterns, shows the formation of single-phase compositions with rhombohedral symmetry. Upon Pr3+ doping at the A-site, the unit cell volume and the B-O-B bond angles are reduced. FTIR spectra present a prominent absorption peak of the in-phase stretching mode (B2g mode) rising from the vibration of the Mn-O bond. Raman spectra at room temperature reveal a gradual shift toward lower frequencies in (Eg) phonon mode with increasing Pr3+ concentration. The M(T) measurements shows a clear ferromagnetic (FM)-paramagnetic (PM) phase transition with increasing temperature. An increase in resistivity and activation energy and a decrease in the metal-semiconductor transition (T M-SC) and Curie temperatures (T C) was observed as a consequence of Pr3+ doping. The results are discussed according to the change of A-site-disorder effect caused by the systematic variations of the A-site average ionic radius 〈r A〉 and A-site-cation mismatch σ 2, resulting in the narrowing of the bandwidth and the decrease of the mobility of eg electrons. The magneto-transport behavior in the whole measured temperature and a magnetic field can be described by a percolation model, which is in agreement with the limited experimental data of the samples for x = 0.075, 0.15 and 0.30. The experimental results confirm that A-site substitution with Pr3+ destroys the Mn3+-O2--Mn4+ bridges and weakens the double exchange (DE) interaction between the Mn3+ (t3 2ge1 g, S = 2) and Mn4+ (t3 2ge0 g, S = 3/2) ions. On the other hand, the Bean and Rodbell model has been successfully used to simulate the magnetization data of the samples with x = 0.15 and x = 0.22. The random replacement of La3+ by Pr3+ is shown to induce more disorder in the system, which is reflected in the increase of the fitted disorder parameter and spin value fluctuation. At a temperature close to room temperature, the maximum magnetic entropy change (ΔS Max) and the relative cooling power (RCP) of La0.52Pr0.15Ba0.33MnO2.98 are found to be, respectively, 1.34 J kg-1 K-1 and 71 J kg-1 for a 1.5 T field change.