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As a widely used herbicide, picloram has been frequently detected in the aquatic environment due to its high leaching potential and low adsorption by soil. To reduce aquatic environmental risk of this herbicide caused by leaching and runoff, five herbicidal ionic liquids (HILs) based on picloram were prepared by pairing isopropylamine, octylamine, octadecylamine, 1-methylimidazole, 4-methylmorpholine respectively. Their physicochemical properties including water solubility, octanol-water partition coefficient, surface activity, leaching, as well as soil adsorption were compared. The results showed that these properties could be adjusted by appropriate selection of counter cations. The HILs with long alkyl chains in cations had low water solubility and leaching characteristics, good surface tension and lipophilicity, as well as high soil adsorption. Compared with currently used picloram in the forms of potassium salts, HIL3 had more excellent herbicidal activity against broadleaf weeds and may offer a lower use dosage. The HILs based on picloram can reduce its negative effects on the aquatic environment and can be used as a desirable alternative to commercial herbicidal formulations of picloram in future.

The 1,4-naphthoquinone derivatives bearing 5,7-dimethoxyl moiety were designed, synthesized, and tested as the antitumor agents against five human cancer cell lines (A549, Hela, HepG2, NCI-H460 and HL-60). All the compounds are described herein for the first time. The structure-activity relationships indicated that the presence of chlorine atom at the 2-position was crucial for the antiproliferative activity. Further, the electrochemical properties of the representative compounds (7e, 8e and 9e) were evaluated and a definite correlation between the redox potential and the antiproliferative activity. The most potent compound 9e displayed significant anti-leukemic activity with IC50 value of 3.8 μM in HL-60 cells and weak cytotoxicity with IC50 of 40.7 μM in normal cells WI-38. In mechanistic study for 9e, the increased numbers of apoptotic cells and increased cell population at G2/M phase correlated with ROS generation. Together, our results suggested that the derivatives of 2-chlorine-1,4-naphthoquinone might be the promising candidates for the treatment of promyelocytic leukemia.

New auxinic herbicide derivatives with high-activity and low-volatility are required urgently to solve the growing problems of weed resistance and volatile drifting which severely limit the application of auxinic herbicides (2,4-D, MCPA and dicamba). In this study, a series of auxinic herbicide derivatives were prepared using 2,4-D, MCPA and dicamba as lead compounds by me-too method. The volatility, greenhouse herbicidal activity against four common weeds and field herbicidal activity were evaluated and a comparative analysis with the corresponding lead compound was made. Results of volatility test indicated that it was possible to get a low-volatile compound even when the reactants were both highly volatile and the compounds with intermolecular hydrogen bond showed the comparatively low volatility. In the greenhouse herbicidal activity test, the compounds with ester bond had faster and higher herbicidal activities and better inhibition phenotypes than the compounds with amide bond. The compounds (R)-ethyl 2-(4-(2-(2,4-dichlorophenoxy)acetoxy)phenoxy)propanoate (3a-9), (R)-ethyl 2-(4-(2-(4-chloro-2-methylphenoxy)acetoxy)phenoxy)propanoate (3a-18) and (R)-4-((1-ethoxy-1-oxopropan-2-yl)oxy)phenyl 3,6-dichloro-2-methoxybenzoate (3b-7) showed lower volatilities and faster and higher activities in the greenhouse and field test than the corresponding lead compound and could be potential herbicides for further development. Keywords: Auxinic herbicide derivative, Herbicidal activity, Volatility, Me-too method