Synthesis, Larvicidal and Acetylcholinesterase Inhibitory Activities of Carvacrol/Thymol and Derivatives

Abstract

In order to produce bioactive derivatives of carvacrol and thymol, nine derivatives of each compound were prepared through modifications the phenolic hydroxyl group. The structures of compounds were confirmed by spectral data from MS, IR and NMR. Carvacrol, thymol and derivatives were submitted to the evaluation of the inhibition of the enzyme acetylcholinesterase, using a colorimetric method in which the inhibition of the enzyme is measured by coloration, and larvicidal activity against Aedes aegypti. Derivatives carvacryl acetate-1b and thymyl hexanoate-2b showed the best results for the inhibition of the acetylcholinesterase enzyme, and for the larvicidal activity the derivatives 1a, 1b, 1c, 3h, 2a, 2b, 2c and 4h showed positive results, emphasizing compound thymyl 4-methoxybenzoate-4h which showed LC 50 values of 23.60 ppm, considered a very good result.

Synergistic interaction between carvacrol and Bacillus thuringiensis crystalline proteins against Cydia pomonella and Spodoptera exigua

“…Rizvi et al (2018) showed that carvacrol inhibited acetylcholinesterase activity in insects of the same order by contact application. Similar activity of carvacrol was found against Diptera (de Mesquita et al 2018;Park et al 2016). In our research, the route of carvacrol application was different and the insects used represented a different order in comparison with the other studies mentioned above.…”

“…Carvacrol or plant extracts with carvacrol as the main component are known to exert negative effects against coleopteran (Szczepanik et al 2018), homopteran (Zekri et al 2016), dipteran (Andrade-Ochoa et al 2018;de Mesquita et al 2018;Giatropoulos et al 2018), lepidopteran (Melo et al 2018), neuropteran (Castilhos et al 2018), and hemipteran (Gaire et al 2019;Rizvi et al 2018) insects. This phytochemical was shown to exhibit contact (Castilhos et al 2018;Melo et al 2018;Rizvi et al 2018), repellent (Giatropoulos et al 2018), and fumigant (Gaire et al 2019) toxicity.…”

“…This phytochemical was shown to exhibit contact (Castilhos et al 2018;Melo et al 2018;Rizvi et al 2018), repellent (Giatropoulos et al 2018), and fumigant (Gaire et al 2019) toxicity. The carvacrol-containing essential oil showed neurotoxic effects and was found to inhibit the acetylcholinesterase enzyme in the contact application against insect pests (de Mesquita et al 2018;Rizvi et al 2018). Carvacrol has been also reported to have insecticidal activity upon ingestion against Hemiptera (Park et al 2017) and Lepidoptera (Tang et al 2011).…”

Synergistic terpene combinations as larvicides against the dengue vector Aedes aegypti Linn.

“…A combination of such terpenes could be a viable and safe agent as mosquito larvicide. Earlier studies that have shown that terpenes (by themselves and in combination) have relevant larvicidal activities against Aedes, Anopheles, and Culex larvae (Benelli et al, ; Govindarajan et al, ; Govindarajan et al, ; Mesquita et al, ; Santos et al, ; Seo et al, ; Silva et al, ).…”

Carvacrol Prodrugs with Antimicrobial Activity Loaded on Clay Nanocomposites

“…Pure carvacrol derivatives showed typical bands of the carvacrol portion, such as the CH symmetric and asymmetric stretching between 2958 and 2861 cm −1 , the isopropyl symmetric and asymmetric bending at 1383-1373 and 1361 cm −1 , and the C=C stretching vibrations at 1622-1445 cm −1 [54]. Additionally, the bands that demonstrated the effective coupling reaction with the amino acids with subsequent formation of an ester group were the C=O stretching vibration at 1761-1755 cm −1 and the CC=O-O symmetric stretching at 1269-1188 cm −1 [55,56]. All these bands, though with lower intensity, were present in the three hybrids samples (WSCP1-VHS, WSCP-2-VHS, and WSCP3-VHS), suggesting that active molecules are adsorbed on mineral clay surfaces without any destruction of functional groups [57].…”