Safe and Sustainable Crop Protection

Description

As the world population grows, agrochemical researchers continue to innovate. This volume contains select innovations and advances in crop protection technology from the ACS Division of Agrochemicals. Contributed chapters focus on biochemistry, such as microbiomes and antibiotics, as well as workflows, including separation, characterization, and analysis. Safe and Sustainable Crop Protection ACS Symposium Series1334 Safe and Sustainable Crop Protection Library of Congress Cataloging-in-Publication Data Foreword Preface The Microbiome of Fruit Flies as Novel Targets for Pest Management Modular Approach to Macrocyclic Picolinamides Workflows for the Structure Elucidation of Impurities in Synthetic Agrochemicals Using Mass Spectrometry Separation of Chiral Molecules in Support of Process Chemistry and Formulations Research Optimization of Critical Parameters in Chiral Analysis of Prothioconazole by Supercritical-Fluid Chromatography–Mass Spectrometry Characterization of Nonextractable Residues in Soil via Kinetics Modeling Creating Environmentally Resilient Agriculture Landscapes Using Precision Agriculture Technology: An Economic Perspective Contract Research, Good Laboratory Practices, and Other Challenges for the Agrochemical Professional Editors’ Biographies Indexes Indexes Author Index Subject Index Preface 1 The Microbiome of Fruit Flies as Novel Targets for Pest Management Invasive Fruit Flies: Small Insects of Big Economic Importance Current Status and Challenges of Fruit Fly Management The Fruit Flies’ Microbiome: Who Are the Players? Microbial Influence on Fruit Flies: Nutrition, Behavior, and Insecticide Resistance Leveraging Microbiomes to Develop Novel Management Strategies for Fruit Flies: Lessons from Different Insects Figure 1. Leveraging the microbiome of fruit flies to develop pest management strategies (using D. suzukii as an example). Suppression of Insect Performance by Modifying the Insect Microbiome Disruption of Microbiomes Incompatible Insect Technique Paratransgenesis Microbial-Based Attractants and Repellents Attractants Repellents Optimization of SITs Using Probiotics Concluding Remarks Acknowledgments References 2 Modular Approach to Macrocyclic Picolinamides Figure 1. Structure of UK-2A. Figure 2. Structure–activity relationship investigations on UK-2A. Improving Molecule Stability Figure 3. Use of a hydrolyzable protecting group to increase the leaf surface stability of UK-2A. Figure 4. Macrocycle CAS-381 contains fewer esters and displays improved stability. Figure 5. Acetoxymethyl ether derivatives of UK-2A and CAS-381. Maximizing Synthetic Accessibility Figure 6. Seven additional scaffolds of CAS-385 with atom variations at the X, Y, and Z positions. Retrosynthesis Strategy Figure 7. Retrosynthetic strategy for the modular construction of X-YZ macrocycles. Synthesis of the Stereotriads Figure 8. Early- and late-stage incorporation of YZ substituents. Figure 9. Interconversion of olefinic and alcohol stereotriads. Stitching the Fragments Together Figure 10. Addition of an alcohol stereotriad into a Boc-aziridine carboxylate under Lewis acidic conditions. Figure 11. Formation of the X = CH2 bond. Macrocyclization Figure 12. Macrocyclization methods to create X-YZ macrocycles. Modular Construction Figure 13. Matching the synthetic inputs to create the desired X-YZ macrocycle. Biology Comparisons Figure 14. Scaffold markush for macrocycle derivatives with variations at the X,Y, and Z positions. Summary Acknowledgments References 3 Workflows for the Structure Elucidation of Impurities in Synthetic Agrochemicals Using Mass Spectrometry Background Figure 1. The role of mass spectrometry in the pipeline. Mass Spectrometry Instruments HRMS Analyzers TOF and Quadrupole TOF Orbitrap Ionization Sources Other MS Technologies Applicable for Small-Molecule Structure Elucidation Figure 2. A typical workflow for impurity identification in synthetic AI samples. Typical Workflow for Impurity Identification Derivatization Figure 3. Derivatization of alcohols with 2-SBA for improved sensitivity in negative ion ESI/MS. Case Studies GC/MS Study of Impurities in a Commercial Chlorpyrifos Sample Figure 4. The total ion chromatograms of (a) Chlorpyrifos and (b) Chlorpyrifos derivatized with BSTFA. Figure 5. The EI and PCI-methane mass spectra of the impurity observed in chlorpyrifos derivatized with BSTFA. Scheme 1. Chlorpyrifos LC/MS Study of Impurities in a Commercial Haloxyfop-P Methyl Ester Scheme 2. Haloxyfop-P Methyl Ester Figure 6. The UV chromatogram of Haloxyfop-P methyl ester. Figure 7. The positive ion ESI mass spectrum of Haloxyfop-P methyl ester showing [M + H]+, [M + Na]+, and [M + K]+. Scheme 3. Major Fragment Ions Generated from Protonated Haloxyfop-P Methyl Ester Figure 8. The positive ion ESI MS/MS spectrum of [M + H]+ ions of Haloxyfop-P methyl ester. Figure 9. The negative ion ESI mass spectrum of Haloxyfop-P methyl ester showing [M − H]-, [M + O − H]+, and [M + O2 − H]+. Figure 10. The positive ion ESI mass spectrum of Imp 1 showing both [M + H]+ and [M + Na]+. Figure 11. The positive ion ESI MS/MS spectrum of [M + H]+ ions of Imp 1. Future Improvements Conclusion Acknowledgments References 4 Separation of Chiral Molecules in Support of Process Chemistry and Formulations Research Introduction Workflow for Development of Chiral Separation Methods Step-by-Step Progression of Chiral Separation Method Development Figure 1. Progression of chiral separation method development. (1) Receive racemic and enantioenriched sample. (2) Identify mobile phase composition. (3) Perform chiral stationary phase screening. (4) Optimize separation on best stationary phase. (5) Run both samples using optimized separation conditions and optimized sample prep. (6) Document method. Key Learnings Figure 2. Mixture of chiral diastereomers (four isomers) and chiral byproducts (two enantiomers). Case Studies Example 1: Interesting Findings—When Your Stationary Phase Behaves Unexpectedly Figure 3. Mixture of four isomers to be separated, containing two pairs of enantiomers. Figure 4. Progression of separation during method development using an OJ chiral stationary phase. (1) 15% IPA/hex at 40 °C. (2) 3% IPA/hex at 20 °C (first injection). (3) 1% IPA/hex at 20 °C. (4) 3% IPA/hex at 20 °C (second injection). Figure 5. Chromatograms of epoxide isomers at 20 °C after (1) equilibration at ≥15% IPA/hex for 1h followed by a blank injection at 3% IPA/hex and (2) equilibration at