Design, Synthesis and Fungicidal Activity of 2-Substituted Phenyl-2-oxo-, 2-Hydroxy- and 2-Acyloxyethylsulfonamides.

Minlong Wang,Zining Cui,Xinghai Li,Zhiqiu Qi,Peiwen Qin,Peng Rui,Caixiu Liu,Ying Du,Mingshan Ji

doi:10.3390/molecules22050738

Abstract

Sulfonyl-containing compounds, which exhibit a broad spectrum of biological activities, comprise a substantial proportion of and play a vital role, not only in medicines but also in agrochemicals. As a result increasing attention has been paid to the research and development of sulfonyl derivatives. A series of thirty-eight 2-substituted phenyl-2-oxo- III, 2-hydroxy- IV and 2-acyloxyethylsulfonamides V were obtained and their structures confirmed by IR, 1H-NMR, and elemental analysis. The in vitro and in vivo bioactivities against two Botrytis cinerea strains, DL-11 and HLD-15, which differ in their sensitivity to procymidone, were evaluated. The in vitro activity results showed that the EC50 values of compounds V-1 and V-9 were 0.10, 0.01 mg L−1 against the sensitive strain DL-11 and 3.32, 7.72 mg L−1 against the resistant strain HLD-15, respectively. For in vivo activity against B. cinerea, compound V-13 and V-14 showed better control effect than the commercial fungicides procymidone and pyrimethanil. The further in vitro bioassay showed that compounds III, IV and V had broad fungicidal spectra against different phytopathogenic fungi. Most of the title compounds showed high fungicidal activities, which could be used as lead compounds for further developing novel fungicidal compounds against Botrytis cinerea.

Highlights

Sulfonyl-containing compounds, which exhibit a broad spectrum of biological activities, comprise a substantial proportion of and play an important role in medicines and in agrochemicals [1,2,3,4,5]
Potassium 2-substituted-phenyl-2-oxoethylsulfonates II, prepared from commercially available substituted acetophenones I by sulfonation with a sulfur trioxide-dioxane adduct and neutralized with potassium bicarbonate, were reacted with oxalyl chloride to give the corresponding 2-substitutedphenyl-2-oxoethylsulfonyl chlorides, which were converted into the title compounds III by amination with 2-trifluoromethyl-4-chlorophenylamine using triethylamine (Et3 N) as catalyst
Bioassays showed that some target molecules might be used as new lead compounds for further development of novel fungicides against B. cinerea

Summary

Introduction

Sulfonyl-containing compounds, which exhibit a broad spectrum of biological activities, comprise a substantial proportion of and play an important role in medicines and in agrochemicals [1,2,3,4,5]. Sulfonyl groups can supply two hydrogen-bond acceptors, and a monosubstituted sulfonamide can supply an additional hydrogen-bond donor [6]. Molecules 2017, 22, 738 size and charge distribution properties as carbonyl, carboxyl and phosphate groups, which can be replaced by a sulfonyl group as a bioisostere to retain or improve bioactivity [7,8,9]. The introduction of a sulfonyl group can modulate the solubility and acid-base property of the functional molecules [10,11]. Since the sulfonyl group contains two hydrogen-bond acceptor centers, reasonable introduction of sulfonyl group can enhance the binding affinity of functional molecules with their target proteins to improve activity through hydrogen bond interactions [12,13]

Methods

Results

Discussion

Conclusion