Synthesis, antibacterial and antifungal evaluation of thio- or piperazinyl-substituted 1,4-naphthoquinone derivatives

A series of S-, S,S-, S,O-, N- and N,S-derivatives from 2,3-dichloro-1,4-naphthoquinone compound <b>1</b> were synthesized in different reaction media and evaluated for their antibacterial and antifungal activities. The structures of the novel products were characterized by spectroscopic methods, such as microanalysis, ¹H NMR, ¹³C NMR and MS. Among the tested compounds <b>9</b>, <b>12</b> and <b>18</b> are the most effective compounds against <i>Candida tenuis</i> as potent antifungal compounds. Compound <b>9</b> is also the most effective compound against <i>Staphylococcus aureus</i> as a potent antifungal compound.