Synthesis, antimicrobial evaluation, molecular docking and theoretical calculations of novel pyrazolo[1,5-a]pyrimidine derivatives

New fused heterocyclic compounds were synthesized starting from dimethyl terephthalate, as a versatile precursor, via its reactions with the appropriate reagents. The structures of the newly synthesized compounds were supported by their spectral data. Some of the newly synthesized compounds exhibited promising antimicrobial activities. Molecular docking studies were carried out on 4-(5-amino-7-(4-bromophenyl)pyrazolo[1,5-a]pyrimidine-6-carbonyl) benzoic acid (17) as the most active compound to evaluate its potential interaction molecular docking against Escherichia coli (PDB.ID: 3t88), StReptococcus pneumoniae (PDB.ID: 2wje), Asperglllus flavus (PDB.ID: 4ynt) and Geotrichum candidum (PDB.ID: 1tgh), respectively. Computational calculations at the DFT/B3LYP/6-31G (d) and HF/6-31G (d) level of the theory have been carried out to examine the equilibrium geometry of the pyrazolo[1,5-a]pyrimidine and harmonic vibrational frequencies, The energy of the HOMO and LUMO and Mullikan atomic charges were also calculated. (C) 2019 Published by Elsevier B.V.