Synthesis and biological activity evaluation of some new mixed azines appended tetrahydro-1,2,4-triazines

A series of 6-acetyl-2,4-diaryl-2,3,4,5-tetrahydro-1,2,4-triazines (<b>2a–2f</b>) was synthesized by double Mannich reaction of the hydrazone <b>1a</b> or <b>1b</b> with formaldehyde and the appropriate amine. A similar reaction of <b>1a</b> with the appropriate diamine afforded the <i>bis</i>(tetrahydro-triazines) <b>3a–b</b>, and <b>4a–b</b>. Whereas, the 6-cinnamoyl derivatives <b>5a</b>-<b>c</b> were obtained by the reaction of <b>2a</b> with the appropriate aldehyde. The hydrazone <b>7</b>, derived from <b>2a</b>, was treated with the appropriate aldehyde or ketone to afford the mixed azines <b>8–12</b> and <b>13–16</b>. The biological activity, antibacterial, antifungal and antioxidants of the most newly synthesized compounds of these derivatives were screened. Compounds <b>2b</b>, <b>3a</b> and <b>7</b> revealed the best results against all screened biological activity