Ounds showed promising bioactivity as implied from docking parameters in Tables 6, 7, which indicates the drug likeness properties against kinase inhibitor, protease and enzyme inhibitors. Alternatively, compounds 8b, 10b, and 12b-c showed no activity because the activities had been out the overlapped area amongst the enzyme inhibitors and drug-likeness molecules.Molecular DockingThe docking studies against 1kzn had been subjected to our selenium compound along with the well-known antibacterial drug “gentamicin.” The 1kzn is actually a code for the 24 kDa gyrase fragment; DNA gyrase is often a principal protein involving in replication and transcription of bacterial circular DNA. A lot of antibacterial drugs are known to target DNA gyrase, inducing bacterial death (Lafitte et al., 2002). In term with the docking study, our compound divided into two groups: Group (A) [9b, 12b, 14e, 14f, and 16d] which have higher antibacterial activity and have score varies from (-6.47 to -7.41) that is reasonably significantly less than the score accomplished by the gentamicin (-8.79). Group (B) [8b, 10b, 12a, 12c, and 14d] which have moderate antibacterial activity and have score varies from (-5.87 to 6.55). As apparent in the docking studies, Tables 3 and Figures 4, five, all selenium compounds interact practically inside the sameChemical Reactivity DescriptorsInterestingly, the computational investigation by DFT is an superb tool in designing of new supplies and attracts attentions of quite a few researchers in current reports in illustration of the biological activities (Hagar et al., 2020a; Almehmadi et al., 2021; Mohammed et al., 2021; Parveen et al., 2021). Lately, the frontier orbitals, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) andFrontiers in Chemistry | www.frontiersin.orgMay 2021 | Volume 9 | ArticleAbdellattif et al.Effective Synthesis of SelenopyridinesSCHEME 2 | Synthesis of hydroselenonicotinonitrile 14d-f.SCHEME three | Synthesis of selenopheno[2, 3-b]pyridine derivative 16d.their energy gaps have been made use of to prove numerous chemical reactivity forms of the biological characters. Moreover, various biological activities for instance antifungal (Joshi et al., 2018, 2020), anticancer (Kumar et al., 2018; Hagar et al., 2019; Khodair et al., 2020), PKCθ medchemexpress antimicrobial (Grover et al., 2000; Malhotra et al., 2017; Kumer et al., 2019), cytotoxic (Aljuhani et al., 2018; Da Costa et al., 2018; Rachedi et al., 2019) activities and also a new-drugdesign field (Lewis, 2003) could possibly be investigated when it comes to the partnership together with the energy of the FMOs. Diverse vital aspects, for instance the possible from the electronic ionization (I = HOMO ) plus the electron affinity of your LUMO (A = LUMO ) might be estimated in the FMOs. Additionally, the FMOs is an outstanding tool to appraise many chemical reactivity descriptors, such as softness (), worldwide hardness (), electronegativity () (an indicator for the electronic acceptance capacity of the compound i.e., Lewis acidity), and electrophilicity () (an appraisal for the reduced power ofelectronic transition), which could be calculated as followed (Ortega et al., 2020) and shown in Table eight. 1 = – (EHOMO + ELUMO ) 2 1 = – (EHOMO – ELUMO ) two 1 = two = 2 (1) (two) (3) (four)Recently, the energy level along with the energy gap on the frontier molecular orbitals (HOMO and LUMO) had been reported to influence the N-type calcium channel list binding affinity in the compounds and to direct the interactive mode with all the receptor proteins.Frontiers in Chemistry | www.frontiersin.orgMay 2021 | Vol.