The discovery of florylpicoxamid, a new picolinamide for disease control

Abstract The natural product UK-2A was transformed postfermentation to fenpicoxamid (InatreqTM active), a new crop protection active ingredient for disease control in wheat and bananas. A second-generation molecule inspired by UK-2A necessitates a nonmacrocyclic structure with fewer stereogenic centers to enable cost-effective large-scale production via total synthesis. Deconstruction of the UK-2A macrocycle led to the identification of key structural elements necessary to provide effective control of disease. Beginning with a nonmacrocyclic fragment containing these structural elements, a new molecule was created using structure–activity relationship studies focused on improving control of wheat leaf blotch caused by Zymoseptoria tritici. These studies led to the discovery of florylpicoxamid (AdaveltTM active), a new active ingredient in the picolinamide class of fungicide chemistry.