Novel Insecticides from Alkylated and Acylated Derivatives of Thymol and Eugenol for the Control of Plutella xylostella (Lepidoptera: Plutellidae)

Abstract

Plutella xylostella cause considerable harm to the production of broccoli, Chinese cabbage, cabbage and cauliflower. The control of P. xylostella is mainly performed using commercial insecticides, which have even led to the emergence of resistant populations. Two easily available natural products found in different plants essential oil, thymol and eugenol, stand up as possible novel agents to control this pest. In this work a series of alkylated and acylated derivatives of eugenol and thymol were synthesized and screened for antifeedant, larvicidal and ovicidal activities against P. xylostella. The results of biological activities assays suggest that the novel 1,1’-[1,8-octanediylbis(oxy)]-bis(4-allyl-2-methoxy-benzene) (5) was the most toxic in the larvicidal test. Compounds 1-butoxy-2-isopropyl-5-methyl-benzene (8) and hexanedioic acid 1,6-bis(2-isopropyl-5-methyl-phenyl)-ester (10) were the most toxic in the ovicidal assay. The compound 8 presented the most antifeedant activity. Most of the compounds obtained were more active than commercially available insecticidal deltamethrin and azadirachtin.

Assessment of Sex-Specific Toxicity and Physiological Responses to Thymol in a Common Bean Pest Acanthoscelides obtectus Say

“…Insecticidal, repellent, antifeedant, oviposition deterrent and growth reducing effects of thymol have been confirmed in stored products ( Kim et al, 2010 ; Szczepanik et al, 2012 ; Brari and Thakur, 2015 ; Oliveira et al, 2017 , 2018 ; Shahriari et al, 2017 ; Wahba et al, 2018 ; da Camara et al, 2022 ), agricultural ( Hummelbrunner and Isman, 2001 ; Wilson and Isman, 2006 ; Pavela, 2011a ; Koul et al, 2013 ; Lima et al, 2020 ; Valcárcel et al, 2021 ) and medically important pest insects ( Pavela, 2011b ; Zahran and Abdelgaleil, 2011 ; Govindarajan et al, 2013 ; Youssefi et al, 2019 ). Influence of thymol on stored products insects depends on insect species, mode of application and sex.…”

Characterization key genes of Arabidopsis seedlings in response to β-caryophyllene, eugenol using combined transcriptome and WGCN analysis

“…Eugenol is a phenolic aromatic ingredient present in clove oil. It not only boosts the antioxidant capacity of cells ( Stone, 2017 ), but only exhibits antimicrobial properties against a range of pathogenic bacteria ( Da Camara et al., 2022 ; Fu et al., 2022 ). It can easily permeate the lipopolysaccharide layer of cell membranes, penetrate cytoplasmic membrane and cytoplasm of gram-negative bacteria, causing intracellular component leakage ( da Silva et al., 2018 ).…”

Liposomal Formulations Loaded with a Eugenol Derivative for Application as Insecticides: Encapsulation Studies and In Silico Identification of Protein Targets

“…Eugenol also exhibits a potent insecticidal activity, and the synthesis of new derivatives can be an important way to modulate the biological activity of these compounds [ 14 ]. A set of O -alkylated eugenol (trivial name for 4-allyl-2-methoxyphenol) derivatives, having a propyl chain with terminals such as hydrogen, hydroxyl, ester, chlorine, and carboxylic acid, and their later epoxidation to give the corresponding oxiranes, was previously published by our research group [ 15 ].…”