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Mosquitoes are the vectors of numerous diseases such as malaria, Dengue and Zika. Controlling mosquito vectors is essential for preventing and managing diseases transmitted by mosquitoes. Larvicides target larvae within their breeding habitats before they mature into adult mosquitoes and disperse. In this study, using α -hexyl cinnamaldehyde (HCA) as a lead compound, three series of derivatives comprising a total of 78 compounds were designed and synthesized. The larvicidal activities of these compounds against Aedes albopictus were evaluated, resulting in the identification of ten promising compounds. Among them, furan-3-ylmethyl cinnamate (compound 2v) and (E)-allyl 3-(4-chlorophenyl)acrylate (compound 4c) exhibited the lowest LC 50 values (8.0 ppm and 7.2 ppm respectively). In a 96-h acute toxicity assay conducted on zebrafish, 2v showed no or very low toxicity with an LC 50 higher than 100 ppm. To elucidate their mode of action, morphological and histopathologic analyses were performed, and the effects of the compounds on the acetylcholinesterase (AChE) and phosphatase activities were evaluated. Results suggested that the active HCA derivatives induce injury to intestinal epithelial cells by inhibiting phosphatase activity, ultimately resulting in the mortality of mosquito larvae. [ABSTRACT FROM AUTHOR]

[Display omitted] • α-Humulene and sclareol showed synergistic inhibitory effect on human pancreatic cancer cells. • The combination strongly decreased the levels of NF-κB, phosphor Akt (pAkt) and Bcl-2, and increased the level of Bax. • The in vivo study showed that HUM and SCL in combination suppressed the growth of Panc-1 xenograft tumors in immunodeficient mice. Both α-Humulene (HUM) and sclareol (SCL) are naturally occurred compounds and have been shown to exert anti-inflammatory and anticancer activities. The effects of these two compounds alone or in combination on pancreatic cancer cells have not been reported. In the present study, we investigated the effects of HUM and SCL on human pancreatic cancer cells cultured in vitro and grown as xenograft tumors in vivo. In the in vitro studies, we found that HUM and SCL in combination synergistically inhibited the growth of pancreatic cancer cells. The combination strongly stimulated apoptosis, and suppressed migration, invasion and sphere formation in pancreatic cells. Studies on the mechanism of action showed that the combination strongly decreased the levels of NF-κB, phosphor Akt (pAkt) and Bcl-2, and increased the level of Bax. Knockdown of NF-κB and Akt by small interfering RNA (siRNA) abrogated the inhibitory effect of HUM and SCL on pancreatic cancer cells. The in vivo study showed that HUM and SCL in combination suppressed the growth of Panc-1 xenograft tumors in immunodeficient mice. Results of the present study indicate that HUM and SCL in combination may represent an effective approach for inhibiting the growth of pancreatic cancer. [ABSTRACT FROM AUTHOR]