Synthesis and crystal structure of phosphonic acid and bisphosphoramidate derivatives: QSAR studies of their anti-fungal potential on Macrophomina Phaseolina (Tassi) Goid

Abstract

A series of phosphonic acid and bisphosphoramidate derivatives were synthesized and characterized. The bioactivities against the fungal pathogen Macrophomina phaseolina and human acetylcholinesterase AChE enzyme were studied using QSAR based on multiple linear regression. L17, with (p-Cl–C6H4–NH) (p-Cl–C6H4)C(H)P(O)(OC2H5)2 skeleton, demonstrated a great mortality on the M. phaseolina mycelial growth by 83% inhibition at 150 mg/L; the other tested derivative showed moderate to weak antifungal activity against the fungus. QSAR model based on the GA-MLR method revealed the importance of 3D descriptors (De, Mor18e, H8m, and Mor30p) on the antifungal activity. It showed good capability in predicting the fungicidal activity of the studied molecules. Another derivative, L5, with (m-CH3–NC5H4–NH)(m-CH3–C6H4)C(H)P(O)(OCH3)2 skeleton displays the most potent anti-AChE activity. The electronic parameters, ΔEL-H, and ELUMO, have the highest contribution of human AChE. The authors suggest that these models could be usefully employed in designing more effective crop protection compounds without side effects on non-target organisms.