Phenols antifungal action

The fungitoxic effect of phenols can be increased by the introduction of nitro groups. Even the introduction of a single nitro group strengthens the antifungal action, but dinitrophenols have been applied most widely as fungicides. Dinitro-... 

Detailed analyses of the change in antifungal activity with chemical modification have appeared.3°>39 Naphthlomate-N is very active, but the other three naphthalene isomer combinations are inert. Various substituted phenols may be used in place of the p-naphthol moiety. Of the N-methyl (essential for activity) anilines tried, hydrogen, methyl, methoxyl, and halogen containing compounds were active whereas nltro, di-methylamino, carboxyl, etc., derivatives were inactive. The carbamates still retained some activity but other variations of the thiocarbamate system, such as the dithiocarbamate derivatives, were devoid of antifungal action. 

FIG. 10.15 Comparatively small effect of pH on the antifungal action of some phenolic ethers on Trichoderma viride. (Simon and Blackman,... 

---