In vitro antifungal activity of some schiffbases derived from ortho-hydroxybenzaldehyde against Fusarium

Schiff bases derivatives from ortho-hydroxybenzaldehyde (salicylaldehyde) were prepared and characterized by infrared spectroscopy and elemental analysis and by measurement of their melting points. indeed,the mode of ultraviolet absorption of schiff bases has carried out in five solvents of different polarity (cyclohexane,toluene,ethanol,dmso and dmf). the tests antifungal activity in vitro of the schiff bases obtained were performed in dmso at concentrations: 01,02,04 and 08 mg/ ml against f. culmorum,f.graminearum and f. verticillioides,using the agar dilution method. the results revealed that the inhibitory power of schiff bases seems to be proportional to the concentration. the inhibition highest of the n-salicylidene-3-methoxyaniline and n-salicylidene-4-chloroaniline at 08 mg/ ml against f. culmorum was 100%. in the case of n-salicylidene-3-methylaniline,n-salicylidene-4-methoxyaniline,n-salicylidene-3-chloroaniline and n-salicylidene-4-chloroaniline at 08 mg/ ml against f. graminearum reaches 100% with the exception of the n-salicyliden-2-nitroaniline at 08 mg/ ml was 31.53,40.92 and 38.29%,proves weakly active against f. culmorum,f. graminearum and f. verticillioides respectively. however,the mode of absorption of n-salicylidene-2-nitroaniline in dmso and dmf indicated the presence of bands above 400 nm; these bands characterize the existence of tautomer keto-amine. indeed,the action of the substituent’s a donor or acceptor (r = ch3-,ch3o-,cl or no2 on the aniline at the ortho,meta or para) and the effect of the solvent influenced the process of the tautomerism and thus the antifungal activity in vitro. © school of engineering,taylor’s university.