Inclusions of Pesticides by β-Cyclodextrin in Solution and Solid State: Chlorpropham, Monuron, and Propanil

Abstract

Persistence and degradation are important factors in determining the safe use of such synthetic products, and numerous studies have been addressed to develop pesticide remediation methods aimed at ameliorating these features. In this frame, the use of different cyclodextrins (CDs) molecules has attracted considerable attention due to their well-known non-toxic nature, limited environmental impact, and capability to reduce the environmental and health risks of pesticides. CDs appear to be a valuable tool for the elimination of pesticides from polluted areas as well as for better pesticide formulations that positively influence their hydrolysis or degradation. The present work investigates the interaction between β-cyclodextrins and three commonly used pesticides (i.e., chlorpropham, monuron, and propanil) both in solution and in the solid state by means of UV-Vis, FT-IR, and X-ray powder diffractometry. We show that such interactions result in all three cases in the formation of inclusion complexes with a 1:1 stoichiometry and binding constants (Kb) of 369.9 M−1 for chlorpropham, 292.3 M−1 for monuron, and 298.3 M−1 for propanil. We also report the energy-minimized structures in silico for each complex. Our data expand and complement the available literature data in indicating CDs as a low-cost and very effective tool capable of modulating the properties that determine the environmental fate of pesticides.

Characterization of Complexes between Imidacloprid and β-Cyclodextrin: Evaluation of the Toxic Activity in Algae and Rotifers

“…For this reason, a series of molecular docking simulations were performed in order to better characterize the structural determinants of the IMI:β-CD inclusion complex. We adopted a docking protocol already used for a small organic compound bound to the β-CD [ 34 ]. The 3D structure of β-CD was downloaded from the protein data bank (PDB), while the IMI structure was found in the ChEBI (Chemical Entities of Biological Interest, , accessed on 17 January 2023) database; both structures were protonated, energetically minimized before their use in docking simulations.…”

Synthesis of Asymmetric Urea Derivatives from COS and Amines: Substrate Selection, Scope Studies, and Mechanism Investigation

“…Carmustine is an antitumor drug commonly used to treat brain tumors . Monuron as a herbicide is widely used in agriculture . Therefore, it is necessary to develop efficient synthetic methods for the preparation of asymmetric ureas.…”