Preparation and fungitoxicity of 3,6-dichloro-and 3,6-dibromo-8-quinolinols

摘要

3,6-Dichloro- and 3,6-dibromo-8-quinolinols were prepared by direct halogenation of 8-nitroquinoline by N-halosuccinimide in acetic acid or by halogenation of the corresponding 6-halo-8-nitroquinoline prepared via aSkraupreaction. The nitro group was reduced to amino and the amine was hydrolyzed to the phenol in 70 sulfuric acid at 220°C. The fungitoxicity of 3,6-dichloro- and 3,6-dibromo-8-quinolinols, as well as intermediates in their preparation, againstAspergillus niger, Aspergillus oryzae, Myrothecium verrucaria, Trichoderma viride, andMucor cirinelloideswas determined. 3,6-dichloro-8-quinolinol is the most fungitoxic analogue of this class of compounds observed to date