We have used bioinformatics to identify drugs for the treatment of COVID-19, using drugs already being tested for the treatment as benchmarks like Remdesivir and Chloroquine. Our findings provide further support for drugs that are already being explored as therapeutic agents for the treatment of COVID-19 and identify promising new targets that merit further investigation. In addition, the epoxidation of Parthenolide 1 using peracids, has been scrutinized within the MEDT at the B3LYP/6-311(d,p) computational level. DFT results showed a high chemoselectivity on the double bond C 3 =C 4 , in full agreement with the experimental outcomes. ELF analysis demonstrated that epoxidation reaction took place through a one-step mechanism, in which the formation of the two new C-O single bonds is somewhat asynchronous.

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The Molecular Electron Density Theory is applied to the [4+2] cycloaddition reaction between cyclopentadiene and gem-substituted ethylene electrophiles. Calculations are made for reactions, activation energies, and reactivity indices. The results of the experiment are perfectly consistent with activation energies, which unequivocally show that this cyclization’s are is highly stereoselective, in addition, based on ELF examination, the mechanism of these [4+2] cycloadditions occurs in two phases, The mechanisms of these reactions demonstrate that the term "pericyclic reaction" is no more relevant in the 21st century and has been replaced by the term "pseudocyclic".

The molecular electron density theory (MEDT) framework has been used to analyze the [3 + 2] cycloaddition reaction (32CA) between 2-methylene-1,3-dithiolane 1,3-dioxide MDD-2 and N-phenylmethanimine oxide nitrone NIT-1 at the B3LYP/6-311 + + G(d,p) level of theory. The Parr functions and the energy studies clearly reveal that this reaction is extremely regioselective, which is in perfect agreement with the experimental results. This 32CA zwitter-ionic type reaction exhibits high free energies of activation between 21.23 and 23.03 kcal mol-1. By analyzing the chemical mechanism in terms of bond evolution theory (BET), which discloses a variety of fluctuations in the electron density along the reaction route, a one-step mechanism with extremely asynchronous transition states is revealed.

In this work the epoxidation reaction of the α- and ɣ-trans himachalene in the presence of meta chloroperoxybenzoic acid (m-CPBA) has been studied within the Density Functional Theory (DFT) method at the B3LYP/6-311G(d,p) level in dichloromethane as a solvent, in order to shed light on the chemo- and stereoselectivity in the course of the reaction. Analysis of the Conceptual Density Functional Theory (CDFT) reactivity indices indicate that the m-CPBA will behave as electrophilic while α- and ɣ-trans himachalene will behave as a nucleophile and the attacks observed experimentally are correctly predicted by the electrophilic Pk + and nucleophilic Pk - Parr functions. The two reactive paths associated with chemo and stereoselectivity approach modes of m-CPBA on C=C reactive sites in α and ɣ-trans himachalene have been analyzed. They showed that m-CPBA reacted as electrophile whereas α- and ɣ- trans himachalene as a nucleophile. The Monoepoxidation of α- and ɣ- trans himachalene leads to the formation of two stereoisomers, on the most substituted double bond "C=C», one of the two is a majority. The diepoxidation reaction of α- and ɣ- trans h