Xyleborus sp beetles are types of ambrosia beetles invasive to the United States and recently also to Mexico. The beetle can carry a fungus responsible for the Laurel Wilt, a vascular lethal disease that can host over 300 tree species, including redbay and avocado. This problem has a great economic and environmental impact. Indeed, synthetic chemists have recently attempted to develop new neonicotinoids. This is also due to severe drug resistance to “classic” insecticides. In this research, a series of neonicotinoids analogs were synthesized, characterized, and evaluated against Xyleborus sp. Most of the target compounds showed good to excellent insecticidal activity. Generally, the cyclic compounds also showed better activity in comparison with open-chain compounds. Compounds R-13, 23, S-29, and 43 showed a mortality percent of up to 73% after 12 h of exposure. These results highlight the enantioenriched compounds with absolute R configuration. The docking results correlated with experimental data which showed both cation-π interactions in relation to the aromatic ring and hydrogen bonds between the search cavity 3C79 and the novel molecules. The results suggest that these sorts of interactions are responsible for high insecticidal activity.

In this research, six neonicotinoid analogs derived from l-proline were synthesized, characterized, and evaluated as insecticides against Xyleborus affinis. Most of the target compounds showed good to excellent insecticidal activity. To the best of our knowledge, this is the first report dealing with the use of enantiopure l-proline to get neonicotinoids. These results highlighted the compound 9 as an excellent candidate used as the lead chiral insecticide for future development. Additionally, molecular docking with the receptor and compound 9 was carried out to gain insight into its high activity when compared to dinotefuran. Finally, the neurotoxic evaluation of compound 9 showed lower toxicity than the classic neonicotinoid dinotefuran.

The results of a preliminary search to determine the levels of organochlorine pesticide residues in the adipose tissue of the inhabitants of three Mexican cities of different socioeconomic characteristics are described herein. The concentrations and percent occurrence of nine compounds found are reported. In general, the samples analyzed had a large number of different organochlorine residues per sample. The results indicate that the inhabitants have been heavily exposed to 1,1,1-trichloro-2,2-bis (p-chloro-phenyl) ethane (DDT), and to a lesser degree, to 1,2,3,4,5,6,-hexachlorocyclohexane (BHC). The mean concentration of 1,1-dichloro-2,2-bis (p-chlorophenyl) ethylene (DDE) in one of the groups (18.36 ppm lipid basis) was one of the highest reported in the literature. It is also noteworthy that DDT was found in only 63, 89, and 55% of the samples from the three cities.

Abstract. Fusarium Dieback, a new and lethal insect-vectored disease can host over 300 tree species including the avocado trees. This problem has recently attracted the attention of synthetic chemist not only to develop new triazol antifungal agents but also due to severe drug resistance to “classic” triazol antifungal agents. Here, a series of novel antifungal triazoles with a p-trifluoromethylphenyl moiety were synthesized and characterized by spectroscopic and spectrometric methods. Most of the target compounds synthesized showed from modest to good inhibitory activity and less phytotoxicity in comparison with the commercially available propiconazol; in particular, compounds 7 and 13 were active against both Fusarium solani and Fusarium euwallaceae. The results showed that compounds 7, 13, and 4 have great potential to be developed as new antifungal agents because of both good antifungal activity and low phytotoxicity. SAR showed that free alcohols and not O-protected compounds significantly influence the activity. Hence, a-methyl-a-1,2,4-triazole emerged as novel compound to develop new ketone-triazole-type antifungal agents for the management of Fusarium Dieback disease Resumen. Fusarium Dieback es una nueva enfermedad letal transmitida por insectos que actúan como vectores y puede atacar a más de 300 especies de árboles, incluidos los árboles de aguacate. Recientemente, este problema ha atraído la atención de los químicos sintéticos para desarrollar nuevos agentes antifúngicos triazólicos debido a la resistencia severa que desarrollan los insectos a los agentes antifúngicos triazólicos "clásicos". Durante este trabajo, se sintetizaron nuevos triazoles antifúngicos que contienen un grupo p-trifluorometilfenilo y se caracterizaron por métodos espectroscópicos y espectrométricos. La mayoría de los compuestos diana sintetizados mostraron una actividad inhibidora de modesta a buena y menos fitotoxicidad en comparación con el propiconazol que es comercialmente disponible; en particular, los compuestos 7 y 13 mostraron ser activos contra Fusarium solani y Fusarium euwallaceae. Los resultados mostraron que los compuestos 7, 13 y 4 tienen un gran potencial para desarrollarse como nuevos agentes antifúngicos debido a la buena actividad antifúngica y su baja fitotoxicidad. SAR mostró que los alcoholes libres y no los compuestos O-protegidos influyen significativamente en la actividad. Por lo tanto, el α-metil-α-1,2,4-triazol surgió como un nuevo compuesto líder para desarrollar nuevos agentes antifúngicos tipo cetona-triazol para el tratamiento de la enfermedad Fusarium Dieback.

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The nanoencapsulation of pesticides in biodegradable polymers confers several advantages to conventional agrochemicals, such as protection against losses due volatilization and degradation of the active ingredient, as well as the augment of water dispersion, allowing for their application on crops without requiring the use of organic solvents that could harm the user and the environment. This characteristics could enhance the productivity, reducing both costs and environmental pollution. In this work the propiconazole fungicide, forming part of a commercial formulation as well as in its pure state, was encapsulated using as carriers the biodegradable polymer poly lactic acid (PLA) and the biodegradable co-polymer poly (lactic-co-glicolic) acid, all with the aim of generate controlled fungicide release systems to augment the efficiency of the treatments of the Fusarium dieback disease. The most efficient system obtained presented nanospheres of 146.28 nm and an encapsulation efficiency over 42%. The antifungal activity tests showed that the use of this nanoencapsulated fungicide system enhances the growth inhibition percentage in 5%, obtaining a formulation that presents good dispersion in water without the need of organic emulsifier agents.

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Asymmetric oxidation reaction is one of the significant pathways in stereoselective reactions, which is a prominent performer in academic and industrial research. However, ligands are vital for planning an ideal metal‐catalyzed asymmetric oxidation reaction as they interact with the metal to construct catalytically active metal complexes, which can catalyze numerous asymmetric reactions. Designing and synthesizing novel chiral ligands is essential for researchers in modern asymmetric synthesis. In this course, exploring the applicability and the survey of hydroxamic acid as a vital ligand has been presented, which is essential for various metal‐catalyzed transformations.