Dielectric behaviour of some arylazo benzothiazine derivatives in relation to its microbial activity

The dielectric loss ε" for some derivatives was measured in dioxane at 20°C in the microwave region (0.2-18 GHz). The data were analyzed into two Debye terms ascribed to two relaxation processes. The first relaxation could be attributed to the rotation of the molecule as a whole while the second relaxation could be attributed to the flexibility of such molecules. In addition a third relaxation which is expected to be in the higher frequency range may be due to the Poley absorption resonance. This relaxation is reasonable for the liberation of dipoles damped by soft collisions. The static dielectric constant for the investigated compounds were measured and the dipole moments were determined. The biological activity of these compounds were tested against a wide range of microorganisms using the disc diffusion method and the minimum inhibitory concentration for the active compounds were determined. A correlation between the activity and the dielectric parameters were achieved