Synthesis of novel benzopyran-connected pyrimidine and pyrazole derivatives a green method using Cu(ii)-tyrosinase enzyme catalyst as potential larvicidal, antifeedant activities.

A series of benzopyran-connected pyrimidine (1a-g) and benzopyran-connected pyrazole (2a-i) derivatives were synthesized Biginelli reaction using a green chemistry approach. Cu(ii)-tyrosinase was used as a catalyst in the synthesis of compounds 1a-g and 2a-i the Biginelli reaction. The as-synthesized compounds were characterized by IR, H NMR, C NMR, mass spectroscopy, and elemental analysis. The as-synthesized compounds were screened for larvicidal and antifeedant activities. The larvicidal activity was evaluated using the mosquito species , and the antifeedant activity was evaluated using the fishes of . The compounds 2a-i demonstrated lethal effects, killing 50% of second instar mosquito larvae when their LD values were 44.17, 34.96, 45.29, 45.28, 75.96, and 28.99 μg mL, respectively. Molecular docking studies were used for analysis based on the binding ability of an odorant binding protein (OBP) of with compound 2h (binding energy = -6.12 kcal mol) and compound 1g (binding energy = -5.79 kcal mol). Therefore, the proposed target compounds were synthesized a green method using Cu(ii)-enzyme as a catalyst to give high yield (94%). In biological screening, benzopyran-connected pyrazole (2h) was highly active compared with benzopyran-connected pyrimidine (1a-g) series in terms of larivicidal activity.