Design, Synthesis, and Biological Activities of Novel 2-Alkylpyrrole Derivatives

To investigate the alkyl analog of insecticide chlorfenapyr, two series of 2-alkyl-4-bromo-5-(trifluoromethyl)pyrrole-3-carbonitriles were synthesized with a cycloaddition as the key step. The target products were characterized by H-1-NMR spectroscopy, elemental analysis, or HRMS. The insecticidal, herbicidal, and antifungal activities of the target compounds were evaluated and found that these compounds did not show much insecticidal activity, but compounds 4, 10, and 11 had very good fungicidal activities against Alternaria solani and Fusarium oxysporum. Moreover, compound 4 had an outstanding inhibition effect against pigweed.