Towards designing of some potential new autoimmune disorder inhibitors using crystal structures and Hirshfeld surface analyses in combination with molecular docking and molecular dynamics simulations

The emergence of multi-drug-resistant autoimmune diseases poses a significant risk to human health and has garnered global attention. In this study, metformin and sulfasalazine have been used as starting materials or control. This research has successfully designed a hundred compounds, to assess their efficacy against two autoimmune disease pathogens: type 1 diabetes and rheumatoid arthritis. The DFT method was engaged to calculate the vibrational frequencies and Frontier Molecular orbitals (FMOs) of the selected compounds. The reactivity and selectivity of the selected compounds are analyzed using parameters like MEP and global reactivity descriptors, which are calculated and interpreted. The Density of state (DOS) of the molecule has been plotted and interpreted. Furthermore, docking results showed favorable interactions of the designed compound D385 with catalytically important amino acid residues. The interactions of the best active D385 when compared with the template and the standard drugs show similar binding sites. DFT studies further confirm the presence of HOMO orbital centered on the isoxazole ring further highlighting its importance for receptor-ligand hydrogen and hydrophobic interactions. The molecular dynamics simulations and MM/GBSA analysis reveal that the inhibitory nature of the designed compound D385 is a proven inhibitor of diabetes type 1 and rheumatoid arthritis inhibitor activities. Our study suggested that the designed compounds showed comparable results to that of metformin and sulfasalazine and may be used for further experimental studies. It can also be used as a pipeline to search for and design new potential autoimmune disease inhibitors. The most promising candidates from computational trials can be examined in a wet laboratory experiment before moving on to clinical trials.