Pyrimidine Schiff Bases: Synthesis, Structural Characterization and Recent Studies on Biological Activities

Area of Science:

• Medicinal Chemistry
• Organic Synthesis
• Structural Chemistry

Background:

• Pyrimidine derivatives exhibit diverse biological activities, including antibacterial and antineoplastic effects.
• Previous research synthesized and evaluated 5-[(4-ethoxyphenyl)imino]methyl-N-(4-fluorophenyl)-6-methyl-2-phenylpyrimidin-4-amine for antibacterial and anticancer properties.

Purpose of the Study:

• To synthesize novel 5-iminomethylpyrimidine compounds with variations in aromatic ring substituents.
• To elucidate the structure-activity relationships of these new derivatives through spectroscopic and crystallographic analyses.
• To compare the biological activities, particularly cytotoxic features, with a previously studied Schiff base.

Main Methods:

• Synthesis of new pyrimidine Schiff bases.
• Structural characterization using ESI-MS, FTIR, and 1H NMR spectroscopy.
• Low-temperature single-crystal X-ray diffraction analysis.
• In silico studies including ADME prediction and molecular docking.

Main Results:

• Successful synthesis and structural confirmation of new 5-iminomethylpyrimidine derivatives.
• Identification of intramolecular N-H∙∙∙N hydrogen bonds and intermolecular C-H∙∙∙F interactions crucial for crystal packing.
• Comparative analysis of cytotoxic activities, with compound 4b showing significant potential.
• Computational investigations provided insights into the pharmacokinetic and binding properties of the most active compound.

Conclusions:

• The synthesized 5-iminomethylpyrimidine derivatives possess promising antibacterial and antineoplastic activities.
• Structural features, including hydrogen bonding and halogen interactions, are critical for their biological efficacy.
• Computational methods complement experimental findings, aiding in the design of future drug candidates.