A series of plumbagin derivatives (4a−4k) containing an amino acid moiety were synthesized under mild esterification conditions in excellent yields (35%−80%) and screened for their antifeedant activities in tobacco caterpillar (Spodoptera litura) and castor semilooper (Achaea janata) using a no-choice laboratory bioassay. The parent compound plumbagin lacked significant activity, but the analogues