N-substituted phenothiazine derivatives as potent antimicrobials: Synthesis and structural characterization

A series of N-substituted phenothiazine derived chloro compounds (3a-3c) and morpholine based compounds (5a-5c) were synthesized by base catalyzed reactions. The molecular structures of synthesized compounds were confirmed by using various spectral techniques viz., FT-IR, ¹H, ¹³C NMR and mass spectroscopy. The strong stretching vibrational bands in the region 1696-1670 cm^-1in FT-IR spectral analysis confirms the presence of carbonyl moiety in the synthesized compounds. The presence of signals in the downfield region of proton NMR of 5a-5c is due to methylene protons which confirms their formation. The antimicrobial investigations was carried out against two gram positive bacterial species such as Bacillus subtilis and Staphylococcusaureus. The antifungal activity was tested against AspergillusflavusandAspergillusniger. The biological results obtained suggests that the microbial growth inhibition was much higher in the chloro based N-phenothiazine derivatives (3a-3c) than its morpholine derivative (5a-5c).