Synthesis of Novel Derivatives of 5,6,7,8-Tetrahydroquinazolines Using α-Aminoamidines and In Silico Screening of Their Biological Activity

Int J Mol Sci. 2022 Mar 29;23(7):3781. doi: 10.3390/ijms23073781.

Abstract

α-Aminoamidines are promising reagents for the synthesis of a diverse family of pyrimidine ring derivatives. Here, we demonstrate the use of α-aminoamidines for the synthesis of a new series of 5,6,7,8-tetrahydroquinazolines by their reaction with bis-benzylidene cyclohexanones. The reaction occurs in mild conditions and is characterized by excellent yields. It has easy workup, as compared to the existing methods of tetrahydroquinazoline preparation. Newly synthesized derivatives of 5,6,7,8-tetrahydroquinazoline bear protecting groups at the C2-tert-butyl moiety of a quinazoline ring, which can be easily cleaved, opening up further opportunities for their functionalization. Moreover, molecular docking studies indicate that the synthesized compounds reveal high binding affinity toward some essential enzymes of Mycobacterial tuberculosis, such as dihydrofolate reductase (DHFR), pantothenate kinase (MtPanK), and FAD-containing oxidoreductase DprE1 (MtDprE1), so that they may be promising candidates for the molecular design and the development of new antitubercular agents against multidrug-resistant strains of the Tubercle bacillus. Finally, the high inhibition activity of the synthesized compounds was also predicted against β-glucosidase, suggesting a novel tetrahydroquinazoline scaffold for the treatment of diabetes.

Keywords: antidiabetic; antitubercular; diarylidencyclohexanone; inhibitor; molecular docking; tetrahydroquinazoline; α-aminoamidine.

MeSH terms

  • Antitubercular Agents* / chemistry
  • Molecular Docking Simulation
  • Molecular Structure
  • Mycobacterium tuberculosis* / metabolism
  • Quinazolines / chemistry
  • Quinazolines / pharmacology
  • Structure-Activity Relationship
  • Tetrahydrofolate Dehydrogenase / metabolism

Substances

  • Antitubercular Agents
  • Quinazolines
  • Tetrahydrofolate Dehydrogenase