Synthesis, In Silico Prediction and In Vitro Evaluation of Antimicrobial Activity, DFT Calculation and Theoretical Investigation of Novel Xanthines and Uracil Containing Imidazolone Derivatives.

Novel xanthine and imidazolone derivatives were synthesized based on oxazolone derivatives as a key intermediate. The corresponding xanthine and imidazolone derivatives were obtained via reaction of oxazolone derivative with 5,6-diaminouracils under various conditions. Xanthine compounds were obtained by cyclocondensation of 5,6-diaminouracils with different oxazolones in glacial acetic acid. Moreover, 5,6-diaminouracils were reacted with oxazolones in presence of drops of acetic acid under fused condition yielding the imidazolone derivatives . Furthermore, Schiff base of compounds were obtained by condensing 5,6-diaminouracils with 4-dimethylaminobenzaldehyde in acetic acid. The structural identity of the resulting compounds was resolved by IR, H-, C-NMR and Mass spectral analyses. The novel synthesized compounds were screened for their antifungal and antibacterial activities. Compounds , , and displayed the highest activity against as revealed from the IC values (1.8-1.9 µg/mL). The compound displayed a significant antifungal activity against (0.82 µg/mL), (1.2 µg/mL) comparing to authentic antibiotics. From the TEM microgram, the compounds , , and exhibited a strong deformation to the cellular entities, by interfering with the cell membrane components, causing cytosol leakage, cellular shrinkage and irregularity to the cell shape. In addition, docking study for the most promising antimicrobial tested compounds depicted high binding affinity against acyl carrier protein domain from a fungal type I polyketide synthase (ACP), and Baumannii penicillin- binding protein (PBP). Moreover, compound showed high drug- likeness, and excellent pharmacokinetics, which needs to be in focus for further antimicrobial drug development. The most promising antimicrobial compounds underwent theoretical investigation using DFT calculation.