Synthesis and Biological Activities of Novel 6‐Alkylamino‐11,12‐dihydro‐11‐arylbenzo[ c ]phenanthridine Derivatives

A series of novel benzo[ c ]phenanthridine derivatives 2a , 2b , 2c , 2d , 2e , 2f , 2g , 2h , 2i , 2j , 2k , 2l , 2m and 3a , 3b , 3c , 3d , 3e , 3f bearing an alkylamino side chain at their 6‐position were synthesized. All of the target compounds were confirmed by 1 H NMR, 13 C NMR, and HRMS, and some of them were also characterized by IR and 19 F NMR. The preliminary bioassays showed that the target compounds displayed fungicidal activities; for example, compound 2l showed 60.0% and 70.0% inhibitive activity against Alternaria solani and Cercospora arachidicola at 50 mg/L, respectively, and some compounds also displayed plant growth‐regulating activities.