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In order to develop a new type of antioxidants with high efficiency, a series of β-ionone thiazolylhydrazone derivatives were designed and synthesized from β-ionone, and their structures were characterized by 1H-NMR, 13C-NMR, FT-IR, and HR-MS. The antioxidant test in vitro indicated that most of the target compounds had high biological activity. Among them, compound 1k exhibited very strong DPPH (1,1-diphenyl-2-picrylhydrazyl radical)-scavenging activity with a half-maximal effective concentration (IC50) of 86.525 μM. Furthermore, in the ABTS (2,2-azinobis (3-ethylbenzothiazoline-6-sulfonate) diammonium salt)-scavenging experiment, compound 1m exhibited excellent activity with an IC50 of 65.408 μM. Their biological activities were significantly better than those of the positive control Trolox. These two compounds, which have good free-radical-scavenging activity in vitro, were used as representative compounds in the anti-browning experiment of fresh-cut potatoes. The results showed that 1k and 1m had the same anti-browning ability as kojic acid, and they were effective browning inhibitors. In addition, it is well known that microbial infection is one of the reasons for food oxidation. Therefore, we investigated the antifungal activity of 25 target compounds against eight plant fungi at a concentration of 125 mg/L. The results indicated that these compounds all have some antifungal activity and may become new potential fungicides. Notably, compound 1u showed the best inhibitory effect against Poria vaporaria, with an inhibition rate as high as 77.71%; it is expected to become the dominant structure for the development of new antifungal agents.

In this paper, four new compounds with quinazolinone structure were designed and synthesized based on the special biological activity of quinazolinone. The four new compounds containing quinazolinone structures were synthesized using a one-pot method after intramolecular cyclization and dehydration catalyzed by aqueous methylamine solution. Their structures were characterized using 1H NMR, 13C NMR, FT-IR, and HRMS, and the crystal structure of 2a was characterized using X-ray diffraction. In their potential antifungal activity tests, it was found that the four newly synthesized compounds exhibited significant antifungal activity against all seven phytopathogenic fungi at concentrations of 150 and 300 mg/L. Among them, the target compound 2c showed the best inhibitory effect against Fusarium oxysporum f. sp. Niveum fungus, with 62.42% inhibition at a concentration of 300 mg/L. Compound 2c is expected to be a leading compound for the treatment of watermelon Fusarium wilt in the future, which is worth further study.

2, 2-methylenebis (4-chlorophenol) (dichlorophenol, Dcp) is a priority pollutant that poses a serious health threat to the public. Thus, the sensitive analysis of Dcp is of great significance. Heteroatom-doped carbon nanomaterials modified electrodes have been proven to be good electrocatalysts for electrochemical sensing application. β-cyclodextrin (β-CD) as a signal amplifier has also been utilized in biosensors. Inspired by these, in this study, a new composite of β-CD and three-dimensional (3D) boron-doped graphene aerogels (BGAs/β-CD) has been designed as a high-performance electrochemical sensing platform for Dcp determination. Graphene aerogels possess high specific surface area, large pore volume and good conductivity, which ensure rapid mass transfer and accelerated electron transfer. Besides, boron doping causes uneven charge distribution on the graphene lattice surface, producing a large amount of flowing π electrons, which provide abundant active sites for the catalytic oxidation reaction of Dcp. In addition, Dcp molecules could be captured into β-CD through host-guest recognition, which can effectively amplify the detection signal. Combining the merits of BGAs and β-CD, the BGAs/β-CD based sensor achieved sensitive detection of Dcp. Under optimized experimental conditions, the oxidation currents and the concentration of Dcp had a good linear relationship within 1.0 nM ∼ 21 μM. The detection limit was estimated as 0.33 nM (S/N = 3). This study might provide a new basis for the fabrication of 3D BG-based aerogel architectural material and its application in Dcp detection. [ABSTRACT FROM AUTHOR]