Search

For exploring novel natural product-derived herbicides, 16 novel α-campholenic aldehyde-based 4-methyl-1,2,4-triazole-thioether compounds were designed, synthesized, and characterized by FT-IR, 1H NMR, 13C NMR, ESI-MS and elemental analysis. The preliminary bioassay showed that, at 100 µg/mL, most of the target compounds displayed significant inhibition activity against root-growth of rape(Brassica campestris L.), with inhibition rates of 85.0%～98.2%(A-class activity level), much better than that of the positive control flumioxazin. In addition, an effective and reasonable 3D-QSAR model was established by CoMFA method in SYBYL-X 2.1.1 software. It was found that, the steric field was the major factor towards the herbicidal activity of the target compounds against B. campestris L., and the introduction of bulky groups into m- and p-position of the benzene ring was favourable to increase the herbicidal activity. This kind of title compounds deserved further study as potential leading compounds for the discovery and development of novel herbicidal agents. [ABSTRACT FROM AUTHOR]

Copyright of Chemistry & Industry of Forest Products is the property of Chemistry & Industry of Forest Products Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Nanopesticides have been proved to be a powerful and promising tool to solve the issues in agriculture. The purpose of the present study was to develop ecofriendly nanopesticide systems by the strategy of comprehensive utilization of two natural biomass resources (bagasse and turpentine oil) because of their incomparable advantages. RESULTS: In this research, a series of nanocellulose carriers ETOCN‐1–ETOCN‐4 (ETOCN, esterified TEMPO‐oxidized cellulose nanofibers) with different degrees of substitution were prepared and characterized by Fourier‐transform infrared (FTIR), X‐ray diffraction (XRD) and transmission electron microscopy (TEM). Then, 21 1,3,4‐thiadiazole‐amide compounds 8a–8u containing gem‐dimethylcyclopropane ring were designed, synthesized and characterized. A preliminary bioassay indicated that compound 8i (R = p‐Br Ph) exhibited broad‐spectrum antifungal activity against the tested fungi. Furthermore, drug‐loading complexes 8i/ETOCN‐1–8i/ETOCN‐4 were fabricated by integration of nanocellulose‐based carriers ETOCN‐1–ETOCN‐4 with bioactive compound 8i, and the drug‐loading capacities, microstructures and sustained‐releasing performance of these complexes were also investigated. According to the observation of scanning electron microscopy (SEM) images of complex 8i/ETOCN‐2, the small‐molecule drug and the carrier formed a well‐distributed and compact complex, which led to the excellent drug‐loading capacity and sustained‐releasing performance in the ethanol/water (1:1, v/v) system. CONCLUSIONS: Complexes 8i/ETOCN‐1–8i/ETOCN‐4 deserved further study as the promising candidates for the development of nanopesticides. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Copyright of Chemistry & Industry of Forest Products is the property of Chemistry & Industry of Forest Products Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A series of N-(4-(N′-substituted sulfamoyl)phenyl)myrtenamides containing a heterocycle were designed and synthesized by a multiple-step procedure using α-pinene as starting material. All the synthesized compounds were characterized and analyzed by GC, HPLC, UV-vis, FTIR, NMR, GC-MS, and ESI-MS. The preliminary bioassay showed that, at 50 μg/mL, the target compounds exhibited a certain antifungal activity against the five tested fungi, in which compound 5f exhibited antifungal activity of 83.2% and 70.0% against Physalospora piricola and Alternaria solani, respectively. Moreover, compound 5d displayed herbicidal activity of 86.0% against the root of rape (Brassica campestris) at 100 μg/mL. [ABSTRACT FROM AUTHOR]

Natural products can provide versatile substructures with potential bioactivity and biocompatibility for exploring bioactive compounds. Herein, to explore novel natural product-derived antifungal agents, 21 unreported L -carvone-based pyrazole-oxime ester compounds 6a-6u were synthesised using L- carvone as raw material, and structurally characterised by means of FT-IR, 1 H NMR, 13 C NMR, and HRMS. The results of the in vitro bioactivity tests showed that the target compounds exhibited certain antifungal activity against the eight tested plant fungi at the concentration of 50 mg/L, especially for Physalospora piricola . The inhibition rates of compounds 6e (R =  m -Cl) and 6c (R =  m -F) against P. piricola were 88.3% and 83.9%, respectively, both better than that of the positive control chlorothalonil. Compound 6e (R= m -Cl) with the most significant antifungal activity deserves further investigation as the potential leading compound. In addition, the structure-activity relationships (SARs) of the target compounds were investigated by establishing an effective three-dimensional quantitative structure-activity relationship (3D-QSAR) model.

The accumulation of residual active herbicides in the environment can cause a series of problems. It is thus meaningful to explore a photoresponsive herbicide, whose activity can be weakened under the action of light to reduce the negative effect. To this purpose, a series of ( E )/( Z )-verbenone oxime ethers were designed, synthesized, and characterized. Oxime ether groups were adopted as the trigger switches. The preliminary screening for herbicidal activity showed that some of them exhibited better or comparable effects than that of the commercial herbicide flumioxazin against Brassica campestris and Echinochloa crusgalli . Meanwhile, five pairs of the target compounds with significantly different herbicidal effects between E - and Z -forms were further investigated for their reversible isomerization reaction and the accompanying variation of herbicidal activity. As a result, the maximum conversion rates were around 50%, and the herbicidal effect of the resulting mixture of E - and Z -isomers decreased outstandingly. The phototransformation mechanism of a pair of isomers ( E )- 4a and ( Z )- 4a was preliminarily explored. Besides, a reasonable and effective 3D-quantitative structure-activity relationship model ( r 2 = 0.984 and q 2 = 0.571) was established and the binding mode was also investigated by molecular docking.