Synthesis and Evaluation of Nematicidal Activity of Compounds Derived from Norbornadiene

Abstract

Nematode is a major problem in agriculture, the effective way to control this pest is through chemical control, but the efficient molecules present in the market have great toxicity to mammals and birds. Thus, there is a constant demand for the development of new nematicide molecules. This study describes the synthesis of 21 novel esters derived from norbornadiene and evaluation of their potential activity against Meloidogyne javanica. The esters 5-25 presented 50% mortality of the nematodes. The acid 3 and the ester 4 caused 96 and 93% mortality of the nematodes, respectively. The lethal concentration to kill 50% of the nematodes (LD 50 ) were determined as being 11.8 μg mL −1 for the acid 3 and 99.4 μg mL −1 for the ester 4. According to the results obtained it is believed that polarity seems to be a key factor for the higher activity of compound 3 compared to structurally similar ester derivatives.

Structure and NMR spectra of bicyclo[2.2.1]hepta-2,5-diene-2,3-dicarboxylic acid and its Anhydride

“…The combined organic extracts were dried over MgSO4, and solvent removed in vacuo to give the title product 2 (1.04 g, 57 %) as a colourless solid, mp 165-170 °C (lit. [4] mp 160-161 °C). For spectroscopic data see below.…”