Marburg Virus- A Threat During SARS-CoV-2 Era: A Review.

In the German towns of Marburg, Frankfurt, and Belgrade in 1967, this single negativestranded RNA virus was initially discovered. The importation of infected grivet monkeys from Uganda is what caused this virus-related sickness. As a result of the early link between viruses and non-human primates, this virus is frequently referred to as vervet monkey sickness. This virus causes Marburg hemorrhagic fever in humans and non-human primates. Human endothelial cells serve as the primary vehicle for replication. According to a 2009 report, the virus was being stored in Egyptian fruit bats (Rousettus aegyptiacus). Body fluids, unprotected sex, broken or injured skin, and other bodily fluids are the main routes of transmission. After the incubation period, symptoms like chills, headaches, myalgia, and stomach pain start to show up. There is no specific medication for such an infection, only hydration therapy and adequate oxygenation are followed. The following diagnostic techniques can be used to confirm the diagnosis: (i) an antibody-capture enzyme linked immunosorbent assay (ELISA); ii) an antigen capture ELISA test; iii) a serum neutralization test; iv) an RT PCR assay; v) electron microscopy; or vi) virus isolation by cell culture. Because MARV is a risk group 4 infection, laboratory staff must take strict precautions (RG-4).

Computational Insights into the Role of External and Local Electric Fields in Macrocyclic Chemical and Biological Systems.

The investigation of the role of the electric field in systems of widespread interest employing computational techniques is an emerging area of research. The outcome of applying an oriented external electric field (OEEF) on the geometric and electronic properties of the chemically unique π-conjugated cyclic carbon ring compounds has been explored with density functional theory (DFT). Distinct changes in the structural and electronic features of such ring compounds are observed upon the application of OEEFs. Importantly, the calculations indicate that a mixed aliphatic-aromatic conjugated ring converts from a singlet to a triplet after the application of an OEEF, suggesting potential applications in optoelectronics for such molecules, without the need for photochemically induced change in the spin state. Furthermore, the influence of built-in local electric fields (LEFs) present in naturally occurring macrocyclic systems such as valinomycin has also been explored. Static and ab initio molecular dynamics (AIMD) calculations indicate that LEFs are the primary driving factor in determining the energetically favoured position of counter anions such as chloride (Cl- ) in the potassium (K+ ) and sodium (Na+ ) coordinated valinomycin macrocycle structures: they exist inside the cage in the case of K+ sequestration by valinomycin and outside for Na+ . This divergence has been proposed to be the determining factor for the selectivity of the valinomycin macrocycle for binding a K+ cation over Na+ .

Unraveling the Hidden Role of the Counteranion in "Cation in a Cage" Systems.

The current work showcases general principles at play in systems consisting of cations present inside molecular cages. Such systems, relevant to chemistry and biology, have been carefully investigated by computational methods. The important Ge(II)-encapsulating cage systems have been studied first. The very fact that such compounds exist appears highly unlikely, given the highly reactive nature of the Ge(II) dication. Our studies reveal what really occurs in solution when such complexes are formed: the Ge(II) dications are actually present as [Ge-X]+ (where X is the "non-coordinating" counterion employed in such systems) during entry and subsequent existence at the center of the cage. Hence, what is actually present is a "pseudomonocation". Interestingly, such pseudomonocation-encapsulated cages are seen to be equally relevant in systems of biological importance, such as for dicationic s block-based ionophores. In explaining such cases, the concept of "isoionicity" is introduced, demonstrating that the counterion-coordinated dications are isoionic with a monocation, such as Li(I), isolated in the same ionophore.

Metal-Free Regioselective Cross Dehydrogenative Coupling of Cyclic Ethers and Aryl Carbonyls.

A highly regioselective, efficient, and metal-free oxidative cross dehydrogenative coupling (CDC) of aryl carbonyls with cyclic ethers has been developed. This method offers easy access to substituted α-arylated cyclic ethers with a high functional group tolerance in good to excellent yields. The regioselectivity of this CDC reaction was confirmed by density functional theory (DFT)-based calculations.

What drives the H-abstraction reaction in bio-mimetic oxoiron-bTAML complexes? A computational investigation.

Monomeric iron-oxo units have been confirmed as intermediates involved in the C-H bond activation in various metallo-enzymes. Biomimetic oxoiron complexes of the biuret modified tetra-amido macrocyclic ligand (bTAML) have been demonstrated to oxidize a wide variety of unactivated C-H bonds. In the current work, density functional theory (DFT) has been employed to investigate the hydrogen abstraction (HAT) reactivity differences across a series of bTAML complexes. The cause for the differences in the HAT energy barriers has been found to be the relative changes in the energy of the frontier molecular orbitals (FMOs) induced by electronic perturbation.