Ring Closure and Ring Opening as Useful Scaffold Hopping Tools in Agrochemistry

Abstract

Ring closing acyclic parts of a molecular scaffold or the opposite manipulation, opening rings to produce pseudo-ring structures, is an important scaffold hopping manipulation. Analogues derived from biologically active compounds through the utilization of such strategies are often similar in shape and physicochemical properties and, therefore, likely to exhibit similar potency. This review will demonstrate how several different ring closure techniques, such as replacing carboxylic functions by cyclic peptide mimics, incorporating double bonds into aromatic rings, tying back ring substituents to a bicyclic structure, cyclizing adjacent ring substituents to an annulated ring, bridging annulated ring systems to tricyclic scaffolds, and exchanging gem-dimethyl groups by cycloalkyl rings, but also ring opening led to the discovery of highly active agrochemicals.

Synthesis of Cyclopeptides Analogues of Natural Products and Evaluation as Herbicides and Inhibitors of Cyanobacteria

“…They show insecticidal, fungicidal, herbicidal, nematicidal, or antiphytoviral activities . In particular, naturally occurring and synthetic peptides and cyclopeptides with phytotoxic, herbicidal, or plantgrowth-regulating activities have been considered as eco-friendly herbicides with application in crop protection . During the last years, the research and development of cyclopeptides as new drug candidates has increased as they present valuable properties compared with their linear precursors.…”

“… 8 In particular, naturally occurring and synthetic peptides and cyclopeptides with phytotoxic, herbicidal, or plantgrowth-regulating activities have been considered as eco-friendly herbicides with application in crop protection. 9 During the last years, the research and development of cyclopeptides as new drug candidates has increased as they present valuable properties compared with their linear precursors. Among other advantages, cyclopeptides present improved metabolic stability, selectivity to the receptors, and can adopt bioactive conformations.…”