Green chemistry approach for rapid synthesis of indol-3-yl-4H-pyran derivatives, biological assessments, and toxicological activities against Cowpea aphid (Aphis craccivora)

Abstract

From diverse or indole-3-carbaldehyde, certain unique indol-3-yl-4H-pyran derivatives were generated by condensing with different nucleophiles. IR, ¹HNMR, and elemental studies have all confirmed their chemical structures. The green catalyst for the formation of indol-3-yl-4H-pyran derivatives is a zinc-linked amino acid complex [Zn(L-proline)₂]. Furthermore, the environmental friendliness of this synthetic technique was investigated by assessing the reusability of the Zn(L-proline)₂ complex over five consecutive cycles with no significant loss of catalytic activity. This novel process has showed substantial advantages in terms of safety, simplicity, stability, mild conditions, a short reaction time, excellent yields, and good purity without the use of organic solvents. The antibacterial properties of the compounds produced were investigated and discovered to be promising. To determine whether compounds are appropriate as possible insecticidal agents, the toxicological activity of the synthesized compounds against Cowpea aphid, Aphis craccivora, was tested using leaf dip bioassay technique toxicity studies performed in the laboratory.

KEY WORDS: One pot synthesis, Zn(L-proline)₂, Indole-3-carbaldehyde, Aqueous media, Microwave irradiation, Cowpea aphid, toxicological activity

Bull. Chem. Soc. Ethiop. 2024, 38(4), 1077-1090.                                                    

DOI: https://dx.doi.org/10.4314/bcse.v38i4.21