Derivatives of 1-benzyl-2-methylbenzimidazoles (BMBIs) were synthesized to evaluate their biological activities against Bombyx mori, a lepidopteran model insect. Synthesized BMBIs exhibited two different biological activities: inhibition of development and acute lethality. From a structural perspective, the activity varied with the position of the substitutions on the 1-benzyl moiety; BMBIs with substitutions on the 2 and/or 4 positions had comparatively high activity in comparison with those with substitutions on the 3-position. There was more activity for the inhibition of development with low doses, and more for acute lethality with high doses. The activity was also affected by the applied stage, that is, application in the 4th instar mostly interfered the larval molting or pupation, whereas that in the 3rd instar caused more acute mortality. Taken together, these results suggest that BMBIs have multiple modes of action.

合成了 1-苄基-2-甲基苯并咪唑 （BMBIs） 的衍生物，以评估它们对鳞翅目模式昆虫 Bombyx mori 的生物活性。合成的 BMBI 表现出两种不同的生物活性：抑制发育和急性致死。从结构角度来看，活性随取代基在 1-苄基部分上的位置而变化;与在 3 位上替换的 BMBI 相比，在 2 和/或 4 位置上替换的 BMBI 具有相对较高的活性。低剂量对发育的抑制活性更大，而高剂量对急性致死的活性更大。活性也受施用阶段的影响，即 4 龄施用主要干扰幼虫蜕皮或化蛹，而 3 龄施用则导致更急性死亡率。综上所述，这些结果表明 BMBI 具有多种作用模式。