Synthesis, Characterization and Biological Activities of Novel (E)-3-(1-(Alkyloxyamino)ethylidene)-1-alkylpyrrolidine-2,4-dione Derivatives

Abstract

Twenty novel tetramic acid derivatives (E)-3-(1-(alkyloxyamino)ethylidene)-1-alkylpyrrolidine-2,4-diones were synthesized by the reaction of 3-(1-hydroxyethylidene)pyrrolidine-2,4-diones with O-alkyl hydroxylamines. The title compounds were confirmed by IR, 1 H NMR, MS and elemental analysis. The structure of compound 6r was further verified by X-ray diffraction crystallography. The bioassays showed that most of the title compounds exhibited noticeable herbicidal and fungicidal activities. R 1 : 6a-e = i-C 3 H 7 , 6f-j = n-C 4 H 9 , 6k-o = t-C 4 H 9 , 6p-t = cyclo-C 6 H 11 . R 2 : 6a, 6f, 6k, 6p = n-C 3 H 7 , 6b, 6g, 6l, 6q = i-C 3 H 7 , 6c, 6h, 6m, 6r = CH 2 -CH=CH 2 , 6d, 6i, 6n, 6s = n-C 4 H 9 , 6e, 6j, 6o, 6t = CH 2 C 6 H 5 .Scheme 2. The synthetic route and the structures of title compounds

3‐Hydrazido and 3‐Hydrazono Derivatives of Tenuazonic Acid and their Herbicide Evaluation

“…3‐(1‐Substituted‐amino)ethylidene‐1 H ‐pyrrolidine‐2,4‐diones (Fig. , B ) and 3‐(1‐(alkyloxyamino)ethylidene)‐1 H ‐pyrrolidine‐2,4‐diones (Fig. , C ) were also found to exhibit significant herbicidal activity.…”

Synthesis and Biological Activities of 3‐Substituted Analogues of Tenuazonic Acid

“…Another two series of compounds, 3‐(1‐substituted amino)ethylidene‐1 H ‐pyrrolidine‐2,4‐diones (Fig. , B ) and 3‐(1‐(alkyloxyamino)ethylidene)‐1 H ‐pyrrolidine‐2,4‐diones (Fig. , C ), were also found to exhibit significant herbicidal activity.…”

“…The structure of TeA was extensively modified to provide various structures with different bioactivities , of which we were interested in the compounds with herbicidal activities. 3‐[(α‐Hydroxy substituted)benzylidene]pyrrolidine‐2,4‐diones (Fig.…”

Studies on the Synthesis and Bioactivities of 4‐Amino Derivatives of Tetramic Acid

“…5‐Substituted derivatives of pyrrolidine‐2,4‐dione showed noticeable herbicidal activities, of which compound B exhibited excellent inhibitory activities against the stalk of E. crus‐galli , with EC 50 values of 94.4 mg/L . 3‐Aminoethylidene‐1 H ‐pyrrolidine‐2,4‐diones ( C ) , 3‐alkyloxyamino derivatives ( D ) , and 3‐semicarbazide derivatives ( E ) that were prepared from 3‐acetyl‐pyrrolidine‐2,4‐diones were found to exhibit significant herbicidal activity. 3‐Cyano ( F ), 3‐sulfonyl ( G ), 3‐aminocarbonyl ( H ), and 3‐hydrazono‐1 H ‐pyrrolidine‐2,4‐diones ( I ) were also evaluated, but they gave only weak herbicidal activity .…”