Three series of novel 2-cyanoacrylates 7a-7f, 9a-9f, 10a-10f containing 1,3,4-thiadiazole ring moieties were synthesized as herbicidal inhibitors of photosystem II (PS II) electron transportation. Their structures were clearly verified by 1 H NMR, 13 C NMR, elemental analysis (or HRMS analysis) and single-crystal X-ray diffraction analysis. Bioassay showed that a suitable group at the 3-position of acrylates was essential for high herbicidal activity. In particular, compound 7e showed the best herbicidal activities and gave 100% inhibitory activity against rape and amaranth pigweed at a dose of 1.5 kg/ha. Introduction of substituent with higher polarity such as sulfinyl or sulfonyl to the 5-position of 1,3,4-thiadiazole decreased herbicidal activities.

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A series of novel 2-cyanoacrylates containing the 1,2,3-thiadiazole ring moiety were synthesized and characterized by 1 H NMR, 13C NMR, elemental analysis and, in one case, by X-ray crystallography. Most of these cyanoacrylates exhibited good herbicidal activities. In particular, (Z)-methoxyethyl-and (Z)-ethoxyethyl-2-cyano-3-isopropyl-3-(4-methyl-1,2,3-thiadiazol-5-yl)methylaminoacrylate 9h and 9g showed 100% herbicidal activities against rape and amaranth pigweed at a dose of 1.5 kg/ha. 2-Cyanoacrylates containing the thiadiazole ring are a new variation of this class of compound which still retain herbicidal activities.

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Eleven new thiazol-containing 1H-1,2,4-triazole derivatives were designed and synthesized by utilizing 3,3-dimethylbutan-2-one as starting material. Their structures were characterized by IR, 1 H NMR, 13 C NMR, and elemental analysis. Furthermore, some compounds' structures were confirmed with MS and X-ray diffraction and the biological activities of these compounds were evaluated, including in vitro fungicidal and plant-growth regulatory activities. The primary bioassay results indicated that these compounds showed low antifungal activities while exhibited promising plant-growth regulatory activities.