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Nanotechnology can be used to protect plants against Fusarium Dieback and the Laurel Wilt, that are new and lethal insect-vectored diseases that can host over 300 tree species, including avocado trees. The vectors of these diseases are beetles members of the Scolytinae subfamily, notoriously difficult to control because they spend most of their lives hidden within galleries. Nevertheless, when tested on avocado bolts, some insecticides (including permethrin) provided a reduction in the number of entrance holes or beetle emergence, but the persistence of pesticide residues might have been influenced by factors like rainfall and sunlight. The present study aims to encapsulate permethrin in polylactic acid nanospheres, conferring protection against losses by physic and chemical factors, ultimately increasing its persistence. The particle size, zeta potential, and encapsulation efficiency obtained were 393nm, -32mV, and 27%, respectively. After 96 h of exposure to UV-A light, the insecticidal activity of unencapsulated permethrin was severely diminished, having a reduction in mortality in scolytinae beetles from 80% to 40%, while the nanoencapsulated permethrin retained a 70%. The study has concluded the potential advantage of formulating permethrin into nanometric biodegradable spheres, enhancing the persistence of the insecticide while removing the use of toxic organic solvents as vehicle for the active ingredient, reducing the environmental impact.)

Microparticles containing the photosensitive spinosad (SP) were obtained using a combination of chitosan (CH) and sodium lignosulfonate (SL) as encapsulating materials to develop a photoprotective system for intake administration. The microparticles were obtained by a spray drying technique and were characterized in terms of morphology (scanning electron microscopy - SEM) and particle size. In vitro release studies showed an initial burst effect that fits very well with the zero order kinetic model and then a slow release of the bioinsecticide, which fits best with the first order model. The results of this work demonstrate that the bioinsecticide carrier system developed with natural polymeric materials presents high stability to photodegradation and adequate insecticide release for use as a strategy to reduce negative impacts on the environment in agronomic practices.

Antecedentes y Objetivos: Hyptis suaveolens es una planta bien conocida en América Latina por sus propiedades medicinales. A pesar de sus diversos usos en la medicina tradicional, hay pocos reportes de su composición química. Además, se conoce su actividad contra bacterias que afectan al ser humano, pero existen pocos reportes acerca de su actividad sobre bacterias fitopatógenas, específicamente sobre aquellas que afectan cultivos. En este contexto los principales objetivos de este trabajo fueron determinar la actividad antibacteriana de hojas de H. suaveolens en bacterias fitopatógenas y su perfil fenólico, con el fin de contribuir al conocimiento de la composición fitoquímica y bioactividad de H. suaveolens para aplicaciones fitosanitarias.Métodos: El material vegetal fue colectado y las partes aéreas se secaron, molieron y extrajeron con metanol. El extracto crudo fue probado contra dos cepas bacterianas fitopatógenas (Chryseobacterium sp. y Pseudomonas sp.). Finalmente, se identificaron y cuantificaron compuestos fenólicos utilizando cromatografía de líquidos de ultra alta resolución acoplada a espectrometría de masas. Resultados clave: El extracto crudo de H. suaveolens mostró una actividad antibacteriana moderada en contra de Chryseobacterium sp., y se identificaron y cuantificaron 14 compuestos fenólicos, destacando al ácido rosmarínico, el cual mostró ser el más abundante, seguido de quercetina-3-glucósido y rutina. Seis compuestos fenólicos fueron identificados y cuantificados por primera vez en H. suaveolens.Conclusiones: En este estudio se demostró la actividad antibacteriana de las hojas de H. suaveolens y su correlación con la identificación y cuantificación de 14 compuestos fenólicos, particularmente con la presencia del ácido rosmarínico.

A fast, safe and accessible multicomponent reaction procedure is reported for the synthesis of symmetric and nonsymmetric benzyl-bisphosphoramidate derivatives. Our key reagents were 1,3-phenylenedimethanamine 3 conjointly with the five different phosphorous chlorides, O, O′-diethyl chlorothiophosphate 1, diphenyl phosphoryl chloride 2, diethyl chlorophosphate 5, N, N, N ′, N′-tetramethylphosphorodiamidic chloride 7 and O, O′-dimethyl chlorothiophosphate 9. A total of seven products were obtained, five of them none reported before. As far as we know, our work constitutes the first approach for the synthesis of nonsymmetric benzyl-bisphosphoramidate derivatives. The presence of our adducts were always confirmed by NMR spectroscopy (1H, 13C and 31P) and mass spectrometry.

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.

Background: Hafnium(IV) tetrachloride efficiently catalyzes the protection of a variety of aldehydes and ketones, including benzophenone, acetophenone, and cyclohexanone, to the corresponding dimethyl acetals and 1,3-dioxolanes, under microwave heating. Substrates possessing acid-labile protecting groups (TBDPS and Boc) chemoselectively generated the corresponding acetal/ketal in excellent yields. Aim and Objective: In this study. the selective protection of aldehydes and ketones using a Hafnium(IV) chloride, which is a novel catalyst, under microwave heating was observed. Hence, it is imperative to find suitable conditions to promote the protection reaction in high yields and short reaction times. This study was undertaken not only to find a novel catalyst but also to perform the reaction with substrates bearing acid-labile protecting groups, and study the more challenging ketones as benzophenone. Materials and Methods: Using a microwave synthesis reactor Monowave 400 of Anton Paar, the protection reaction was performed on a raging temperature of 100°C ±1, a pressure of 2.9 bar, and an electric power of 50 W. More than 40 substrates have been screened and protected, not only the aldehydes were protected in high yields but also the more challenging ketones such as benzophenone were protected. All the products were purified by simple flash column chromatography, using silica gel and hexanes/ethyl acetate (90:10) as eluents. Finally, the protected substrates were characterized by NMR 1H, 13C and APCI-HRMS-QTOF. Results: Preliminary screening allowed us to find that 5 mol % of the catalyst is enough to furnish the protected aldehyde or ketone in up to 99% yield. Also it was found that substrates with a variety of substitutions on the aromatic ring (aldehyde or ketone), that include electron-withdrawing and electrondonating group, can be protected using this methodology in high yields. The more challenging cyclic ketones were also protected in up to 86% yield. It was found that trimethyl orthoformate is a very good additive to obtain the protected acetophenone. Finally, the protection of aldehydes with sensitive functional groups was performed. Indeed, it was found that substrates bearing acid labile groups such as Boc and TBDPS, chemoselectively generated the corresponding acetal/ketal compound while keeping the protective groups intact in up to 73% yield. Conclusion: Hafnium(IV) chloride as a catalyst provides a simple, highly efficient, and general chemoselective methodology for the protection of a variety of structurally diverse aldehydes and ketones. The major advantages offered by this method are: high yields, low catalyst loading, air-stability, and non-toxicity.

The cuticle is a critical barrier covering the surface of plant aerial organs. It is associated with important physiological and biological fruit traits, but few studies on this structure have been conducted in tropical fruit such as mango. Here, we have reported on a detailed investigation on the cuticle of six cultivars of mangoes (Kent, Tommy Atkins, Manila, Ataulfo, Criollo and Manililla), by combining several advanced microscopy tools and chemical analyses. All mango cultivars exhibited high variability in cuticle architecture, epicuticular wax layer (EWL) deposition, and different pattern of changes in cutin monomers. Mango cultivars exhibited different water transpiration rates, firmness and fruit quality appearance during postharvest shelf life (PSL), which could not be simply explained by an isolated cuticle structural feature. However, mango cuticles of premium mangos such as Kent, Tommy and Ataulfo displayed prominent cuticle deposition during PSL compared to other cultivars. Tommy fruit with large wax deposition, marginal number of lenticels and prominent cuticle thickening during PSL, exhibited lower percentage of weight lost by transpiration and less visual deterioration of all mango cultivars studied. In contrast, Criollo fruit, with a significant number of lenticels, small EWL, and marginal cuticle thickening during PSL were associated with the highest rate of water transpiration, fruit deterioration, and abscisic acid content. Our results partially explain the resistance patterns to fruit fly attack documented in earlier studies, clearly showing that cultivars such as Criollo are highly susceptible whereas Tommy, Kent, and Ataulfo are resistant because of the cuticle characteristics described in this study.

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...

A novel three-component one-pot reaction procedure was designed for the synthesis of symmetric and asymmetric bisphosphoramidate derivatives. Our key reactants were a set of four aliphatic diamines, which individually react with two different phosphoryl chloride derivatives (N,N,N′,N′-tetramethylphosphorodiamide chloride and diphenyl phosphoryl chloride). A total of 10 products, six of them none reported before, were synthetized. The proposed experimental procedure does not involve any catalyst and proceeds under routine experimental conditions (room temperature and 1 atm). Each synthesized compound was characterized by NMR (1H, 13C, and 31P) spectroscopy and mass spectrometry.

In the present study we evaluated six α,β-unsaturated amides named piperlotines (for being isolated originally from Piper species) as new in vivo anti-inflammatory agents. In addition, we report the mechanosynthesis of two of them by mechanochemical activation of a Horner-Wadsworth-Emmons reaction. The reaction of β-amidophosphonate 4, an aromatic aldehyde and K2CO3 under grinding in a mortar and pestle afforded piperlotines 5-6 in good yields (70-88%) in short reaction times, obtaining only (E)-diastereomer. Piperlotines previously prepared were tested as anti-inflammatory and antibacterial agents. In this respect, derivatives 2 and 6 exhibited excellent in vivo anti-inflammatory activity on mice, especially trough topical administration (TPA acute inflammation model). Furthermore, piperlotine A, and compounds 2 and 6 had slight antimycobacterial activity against Mycobacterium tuberculosis (MIC = 50 µg/mL). In conclusion, the solvent-free mechanosynthesis of piperlotines produced valuable compounds that could serve as templates for further investigation in the search of better drug-like compounds for the treatment of inflammatory diseases. Resumen. En la presente investigación se evaluó la actividad anti-inflamatoria in vivo de seis amidas α,β-insaturadas, identificadas en la literatura como piperlotinas debido a su inicial aislamiento a partir de especies vegetales del género Piper (como las pimientas). La reacción del β-amidofosfonato 4 con un aldehído aromático y K2CO3 en molienda con mortero y pistilo produjo las piperlotinas 5-6 con buenos rendimientos (70-80%) en tiempos cortos de reacción, obteniendo solamente el diastereoisómero (E). Las piperlotinas preparadas se evaluaron como agentes anti-inflamatorios y antibacterianos, observando excelente actividad anti-inflamatoria para los derivados 2 y 6, especialmente cuando se probaron mediante administración tópica (modelo de inflamación aguda por TPA). Además, la piperlotina A y los derivados 2 y 6 mostraron actividad antibacteriana contra Mycobacterium tuberculosis (MIC = 50 µg/mL). En conclusión, la síntesis de piperlotinas a través de molienda en condiciones libres de disolvente generó importantes productos que pueden ser utilizados como punto de partida para generar nuevos compuestos bioactivos para el tratamiento de padecimientos relacionados con la inflamación.

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.

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.

Fifteen plant species from a protected cloud forest (CF) in Veracruz, Mexico, were screened for their in vitro capacity to inhibit the growth of the phytopathogenic bacteria Chryseobacterium sp., Pseudomonas cichorii, Pectobacterium carotovorum and Pantoea stewartii, causal agents of damage to crops like 'chayote', lettuce, potato and corn. As a result, the bioactivity of Turpinia insignis and Leandra cornoides is reported for the first time against Chryseobacterium sp. and P. cichorii. In addition, 24 and 18 compounds not described for these species were dereplicated by an UPLC/MS-MS method, respectively. The identified compounds included simple phenols, hydroxycinnamic acids, flavonoids and coumarins. The antibacterial assay of 12 of them demonstrated the bacteriostatic effect of vanillin, trans-cinnamic acid, scopoletin and umbelliferone against Chryseobacterium sp. These findings confirm for the first time the value of the CF plants from Veracruz as sources of bioactive natural products with antimicrobial properties against phytopathogenic bacteria.

The first diastereoselective total synthesis of 5-substituted morpholine-3-phosphonic acids is reported. The principal feature of the synthesis is the introduction of a dimethyl phosphonate group into 5-substituted morpholin-3-ones. The procedure is based on the preparation of N -Boc-( S )-5-phenyl- and N -Boc-( S )-5-benzylmorpholin-3-one from l -phenylglycine and l -phenylalanine methyl esters, followed by the formation of the 3-methoxylated compounds and subsequent reaction with trimethyl phosphite in the presence of BF 3 ·OEt 2 . Diastereoselectivity in the formation of cis -disubstituted products is in agreement with the nucleophilic addition to other methoxylated derivatives.

Bioassay-guided fractionation of an active crude extract (EtOAc) of polyfollicles of Magnolia vovidessi, an endemic medicinal plant of the cloud forest of Mexico, led to the isolation and identification of shizukolidol (1), an eudesmane-type sesquiterpenoid lactone that showed antibacterial activity against the economically important phytopathogenic bacterium Chryseobacterium sp. (MIC= 400 μg/mL). In addition, 4α,8β-dihydroxy-5α(H)-eudesm-7(11)-en-8,12-olide 8 (2), rutin, scopoline and scopoletine were also isolated as were mexicanin, parthenolide, costunolide, astragalin, quercetin, hesperidin, p-coumaric acid, chlorogenic acid, vanillin, vanillic acid, 4-hydroxybenzoic acid, protocatechuic acid and shikimic acid identified by a dereplication-like procedure using LC-ESI-MS/MS. Rutin displayed mild anti-oomicite activity against phytopathogen Phytophthora cinnamomi.

Diastereoselective nucleophilic addition of trimethyl phosphite to an N-acyliminium intermediate derived from substrate (I) gives cyclic α-aminophosphonates.