Derivatives of pesticides with an α‐amino acid function: Synthesis and effect on threonine uptake

Systemicity of agrochemicals is an advantageous property for controlling phloem sucking insects, as well as pathogens and pests not accessible to contact products. After the penetration of the cuticle, the plasma membrane constitutes the main barrier to the entry of an agrochemical into the sap flow. The current strategy for developing systemic agrochemicals is to optimize the physicochemical properties of the molecules so that they can cross the plasma membrane by simple diffusion or ion trapping mechanisms. The main problem with current systemic compounds is that they move everywhere within the plant, and this non‐controlled mobility results in the contamination of the plant parts consumed by vertebrates and pollinators. To achieve the site‐targeted distribution of agrochemicals, a carrier‐mediated propesticide strategy is proposed in this review. After conjugating a non‐systemic agrochemical with a nutrient (α‐amino acids or sugars), the resulting conjugate may be actively transported across the plasma membrane by nutrient‐specific carriers. By applying this strategy, non‐systemic active ingredients are expected to be delivered into the target organs of young plants, thus avoiding or minimizing subsequent undesirable redistribution. The development of this innovative strategy presents many challenges, but opens up a wide range of exciting possibilities. © 2018 Society of Chemical Industry

Section: Carrier‐mediated Propesticide Strategies For Improving Agrocmentioning

confidence: 94%

Section: Carrier‐mediated Propesticide Strategies For Improving Agrocmentioning

confidence: 99%

Section: Carrier-mediated Propesticide Strategies For Improving Agrocmentioning

confidence: 99%

Section: Carrier-mediated Propesticide Strategies For Improving Agrocmentioning

confidence: 99%

“…The radioactivity appears in white. Tissues are shown at 7 × magnification (fromDufaud et al, 1994) 52.…”

mentioning

confidence: 99%

See 3 more Smart Citations

Vectorizing agrochemicals: enhancing bioavailability via carrier‐mediated transport

Marivingt-Mounir

et al. 2019

The influence of steric configuration of phenazine‐1‐carboxylic acid‐amino acid conjugates on fungicidal activity and systemicity

Zhu

Hsiang

et al. 2019

BACKGROUND Conjugating an amino acid onto existing fungicidal parent structures has been demonstrated to be an effective way to endow non‐phloem mobile fungicides with phloem mobility. To alter the systemicity of the fungicide PCA (phenazine‐1‐carboxylic acid), 10 amino acids derivatives of this fungicide were designed and synthesized, and their synthesis, characterization, phloem and xylem mobility in Ricinus communis L, and their fungicidal activity in vitro are described. RESULTS The systemicity experiments in Ricinus communis system demonstrated that all conjugates exhibited obvious phloem mobility compared with non‐phloem‐mobile PCA, and the introduction of an L‐amino acid to PCA more greatly enhanced the phloem mobility. The five D‐amino acid conjugates exhibited higher xylem mobility than that of PCA and of each corresponding L‐amino acid conjugate. Most conjugates were found to exhibit moderate in vitro fungicidal activities against six pathogenic fungi, which were lower than that of PCA. The results of the bioassay showed fungicidal activities of PCA‐amino acid conjugates associated not only with different amino acids, but also with their conformation. Conjugation with D‐amino acid contributed to the in vitro fungicidal activities of PCA‐amino acid conjugates. CONCLUSIONS The current research offers a new strategy for enhancing the systemicity of non‐phloem‐mobile fungicides and presents some useful information on the effects of introducing amino acids of different steric configurations on the fungicidal activity, phloem and xylem mobility of the parent fungicide. © 2019 Society of Chemical Industry

Synthesis, phloem mobility and induced plant resistance of synthetic salicylic acid amino acid or glucose conjugates

Guichard

Camera

et al. 2022

BACKGROUND The growing demand for food, combined with a strong social expectation for a diet produced with fewer conventional agrochemical inputs, has led to the development of new alternatives in plant protection worldwide. Among different possibilities, the stimulation of the plant innate immune system by chemicals represents a novel and promising way. The vectorization strategy of an active ingredient that we previously developed with fungicides can potentially extend to salicylic acid (SA) or its halogenated analogues. RESULTS Using the click chemistry method, six new conjugates combining SA or two mono‐ or di‐halogenated analogues with L‐glutamic acid or β‐D‐glucose via a 1,2,3‐triazole nucleus have been synthesized. Conjugate 8a, which is derived from SA and glutamic acid, showed high phloem mobility in the Ricinus model, similar to that of SA alone despite a much higher steric hindrance. In vivo bioassays of the six conjugates against two maize pathogenic fungi Bipolaris maydis and Fusarium graminearum revealed that, unlike SA, the amino acid conjugate 8a with good phloem mobility exerted a protective effect not only locally at the application site, but also in distant stem tissues after foliar application. Moreover, compounds 8a and 8b induced up‐regulation of both defense‐related genes ZmNPR1 and ZmPR1 similar to their parent compounds upon challenge inoculation with B. maydis. CONCLUSION The vectorization of salicylic acid or its halogenated derivatives by coupling them with an α‐amino acid can be a promising strategy to stimulate SA‐mediated plant defenses responses against pathogens outside the application site. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.