Synthesis and biological activity of novel pinanyl pyrazole acetamide derivatives

Abstract

Novel pinanyl pyrazole derivatives were synthesized from nopinone and their bioactivities were also examined in this paper. The intermediate compounds 3-arylidenenopinones 2a~2g were synthesized by condensation of aromatic aldehydes and nopinone, and pinanyl pyrazole derivatives 3a~3g were subsequently obtained by cyclization and dehydroaromatization of compounds 2a~2g and hydrazine hydrate in the circumstance of N,N-dimethylformamide (DMT). The target compound pinanyl pyrazole acetamide derivatives 4a~4g were synthesized by alkylation using 2-chloroacetamide as the alkylating agent under the condition of base catalysis. The structures of synthesized compounds were characterized by 1H NMR, 13C NMR, IR, HRMS, and X-ray diffraction analysis. Biological activities evaluation of compounds 3a~3g and 4a~4g were performed including antibacterial and insecticidal activities on Tinocallis kahawaluokalani. Test results showed that compound 4g was a more potent bactericide and fungicide than others because of its good activities against bacteria and fungi; furthermore, compound 4g had shown the better insecticidal activity against Tinocallis kahawaluokalani than the others.