Synthesis And Biological Activities Of1-[1-(Pyrrolin-2-one-3-yl)Ethylidene]-4-Alkylthiosemicarbazide Derivatives

Tenuazonic acid(TeA) is a phytotoxin produced by several fungies including Alternaria alternata, A. longipes and A. tenuissima. Its chemical name is3-acetyl-4-hydroxy-5-sec-butylpyrrolin-2-one. TeA shows good biological activities as antitumour, antivirus, antibacterial, pesticidal and herbicidal activities. Thiosemicarbazone derivatives have been found exhibiting antibacterial, antifungal, antitumour, antivirus and antiparasitic activities as well. In this paper,1-[1-(pyrrolin-2-one-3-yl)ethylidene]-4-alkylthiosemicarbazide derivatives were synthesized with TeA analogs and N4-substitutedthiosemicarbazide, the TeA analogs were made by modifing C-1and C-5of TeA. Finally, the antifungal and herbicidal activities of these derivatives were preliminarily reaserched.Firstly,15kinds of3-acetyl-4-hydroxypyrrolin-2-one compands, which include N-substitued-3-acetyl-4-hydroxypyrrolin-2-one (A1-A4),3-acetyl-4-hydroxy-5-alkyprroline-2-one (A5-A8) and3-acetyl-4-hydroxy-5-substitutedbenzylidenepyrrolin-2-one (A9-A15), were synthsized with substituted amines and amino acids as raw materials. Then,22kinds of1-[1-(pyrrolin-2-one-3-yl)ethylidene]-4-alkylthiosemicarbazide derivatives (C) were synthsized by A1-A15reacting with two kinds of N4-substitutedthiosemicarbazide (B). The structures of the compounds C were all confirmed by1H NMR, MS, IR and elemental analysis.The antifungal activities of the compounds C were tested by using Rhizoctonia cerealis, Fusarium graminearum and Colletotrichum coccodes. And the herbicidal activities were determined by Brassica napus and Echinochloa crusgalli. The results indicated that the compounds C exhibited certain herbicidal activities and antifungal activities at the concentration of100μg/mL. C4, C8, C9and C11exhibited inhibition rates over40%to Rhizoctonia cerealis and C4exhibited inhibition rate over40%to Colletotrichum orbiculare, while C18, C20and C21exhibited inhibition rates over50%to the root of Brassica napus and the EC50of C18was6.97μg/mL, C5, C6, and C8, C11exhibited inhibition rates over50%to the root and bud of Echinochloa crusgall respectively.