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Natural products are an abundant and environmentally friendly source for controlling plant pathogens and insect pests. Toward the development of new natural product-based pesticides, here, a series of osthole-based isoxazoline derivatives were prepared by [3 + 2] annulation and evaluated for their insecticidal activities and toxicities. The structures of all osthole-based isoxazoline derivatives were characterized by various spectral analyses, and derivative

Infections caused by multidrug-resistant (MDR) bacteria are increasing worldwide, and with limited clinically available antibiotics, it is urgent to develop new antimicrobials to combat these MDR bacteria. Here, a class of novel amphiphilic xanthohumol derivatives were prepared using a building-block approach. Bioactivity assays showed that the molecule

To improve the insecticidal activity of (+)-nootkatone, a series of 42 (+)-nootkatone thioethers containing 1,3,4-oxadiazole/thiadiazole moieties were prepared to evaluate their insecticidal activities against

Magnolol and honokiol, derived from a Magnolia officinalis Rehd. et Wils, are a class of natural biphenolic lignans. Currently, the discovery of new α-glucosidase inhibitors from natural analogues is of interest. Here, four series of thirty new Mannich base analogues of magnolol/honokiol were prepared and evaluated for their α-glucosidase inhibitory activities. Among these Mannich base analogues of magnolol/honokiol, 3k and 3l exhibited more potent inhibitory effects on α-glucosidase than the reference drug acarbose, and their IC

Many phytopathogenic fungi can easily infect crops, resulting in crop yield reductions. In continuation of our effort to develop natural product (NP)-based antifungal agents, a series of N -phenylpyrazole sarisan hybrids 6a - v were prepared via I 2 -mediated oxidative cyclization, and their structures were determined by various spectral analyses including IR, 1 H NMR and ESI-MS. Among all N- phenylpyrazole sarisan hybrids, compounds 6a , 6b , 6e , 6i , 6j and 6r showed more potent antifungal activity against at lest two phytopathogenic fungi than the commercial fungicide hymexazol. In particular, compound 6a exhibited more broad-spectrum and promising antifungal activity against three phytopathogenic fungi ( V. mali , F. oxysporum f.sp.niveum , and F. graminearum ) with the EC 50 values of 18.5, 37.4 and 12.6 μg/mL, respectively. Moreover, the structure-activity relationships (SARs) were also observed. Additionally, compounds 6a and 6e also exhibited relative low toxicity on normal LO2 cells. This work indicates that these N -phenylpyrazole sarisan hybrids would shed light on developing novel NP-based antifungal agents.

Honokiol, isolated from a traditional Chinese medicine (TCM) Magnolia officinalis, is a biphenolic compound with several biological activities. To improve and broaden its biological activity, herein, two series of honokiol thioethers bearing 1,3,4-oxadiazole moieties were prepared and assessed for their α-glucosidase and SARS-CoV-2 entry inhibitory activities. Among all the honokiol thioethers, compound 7l exhibited the strongest α-glucosidase inhibitory effect with an IC

Many phytopathogenic fungi cause severe damage to crop yields. In continuation of our research aimed at the discovery and development of natural products-based fungicides, a series of thirty-one sarisan attached 3-phenylisoxazolines were synthesized and evaluated for their antifungal activities against five phytopathogenic fungi ( B. cinerea , C. lagenarium , A. solani, F. solani , and F. graminearum ). Among all title sarisan derivatives, compounds IV2 , IV14 and IV23 showed potent antifungal activity against some phytopathogenic fungi. In particular, compound IV2 exhibited a broad-spectrum and more potent antifungal activity against A. solani , F. solani, and F. graminearum than the commercial fungicide Hymexazol. In addition, compounds IV2 , IV14 and IV23 also displayed relative low toxicity on normal NRK-52E cells. This work will give some insights into the development of sarisan derivatives as new fungicide candidates in plant protection.

In order to provide consumers with high-quality real estate products and meet their purchase needs, this paper proposes a novel location selection method of real estate developers based on big data technology. This method combines the big data technology, and gives full play to the characteristics and advantages of big data technology, especially data acquisition and data mining. In addition, based on literature research and questionnaire survey, this paper constructs structural equation model from the influencing factors of consumers' purchase choice, and then provides feasible path for real estate open development site selection. Based on this, the model constructed by this method is also combined with quantitative analysis method, and then the specific factor structure is obtained, and the relationship between variables is fitted. The experimental results show that the method can help real estate developers to choose a reasonable development location, and better meet the purchase preferences of consumers.

Natural products (NPs) are very important sources for the development of new drugs. Merrillianone and cycloparvifloralone, isolated from the roots, stems, and fruits of Illicium henryi Diels, are two natural sesquiterpene compounds. In continuation of our effort to discovery more effective neurotrophic compounds from NPs, a series of novel merrillianone/cycloparviforalone based esters 2a-i, 3a-g and 3i-q were prepared and their structures were characterized by 1H NMR, 13C NMR and IR spectral analyses. Furthermore, the spatial structure of compound 2h was unambiguously confirmed by X-ray crystallography. The neurite outgrowth-promoting activity results indicated that most of the target derivatives exhibited more potent neurite outgrowth-promoting activity than merrillianone and cycloparviforalone. Among all target derivatives, the neurite outgrowth-promoting activity of compounds 2a, 3a and 3b was about 2-fold stronger than that of their precursors merrillianone and cycloparviforalone, respectively. Besides, compounds 2a and 3a displayed relatively low cytotoxicity to normal GES-1 cells. Moreover, these derivatives had good hydrolytic stability. Finally, some interesting results of the structure-activity relationships (SARs) were also discussed. This work will pave the way for the development of merrillianone/cycloparviforalone derivatives as potential neurotrophic agents.

Unmanned aerial vehicles (UAVs) are widely used in industry and military scenarios due to the advantages of low-cost. For drones using lithium-ion batteries as the energy storage component, accurate state estimation plays an important role in the properly decision making and safely control and maintenance. However, under dynamic operating conditions, only one state is often estimated, in fact there is often a certain correlation between each state, ignoring this will lead to inaccurate estimation results. To address these challenging issues, this paper proposes a joint estimation method for lithium-ion battery’s state-of-charge (SOC) and state-of-power (SOP). Firstly, a method based on Long Short-Term Memory (LSTM) is used to predict the SOC of lithium batteries. There is no need to build a complex battery model. Based on the prediction results, according to the coupling relationship between SOC and SOP, the multi-parameter constraint method is used to obtain the estimated SOP value in a period of time. The experiment was conducted based on the battery simulation data. The results based on the lithium-ion battery simulation data show that the method used in this paper can accurately predict the battery SOC and SOP state parameters.

The perfluorooctanoic acid (PFOA) poses a high risk for aquatic organisms. Nevertheless, the current toxicity studies rarely report how PFOA affects different cell populations during the embryonic development of fish. Here, the zebrafish embryos at 2-30 hpf were exposed to 1-100 μg/L PFOA. The heartbeat and locomotor behavior were significantly decreased after ≥ 25 μg/L PFOA exposure. The single-cell RNA sequencing showed that PFOA exposure influenced nine cell populations, including heart cells, hatching gland cells, macrophages, lens cells, ionocytes, melanoblasts, optic cup cells, periderm cells, and differentiating neurons cells. Among them, heart cells were the most affected cell population. Functions of cardiac muscle contraction, actin cytoskeleton and oxygen binding were significantly changed in the heart cells, which were involved in the altered expressions of tnni2a.4, acta1a, atp1a1a.2, mylpfa, and so on. Besides, the changes of apoptotic process, innate immune response, and translation in lens cells, hatching gland cells, macrophages and ionocytes should also be of concern. Our study indicates that 2-30 hpf of embryonic development is the sensitivity window for the PFOA exposure. Identification of the target cell population provides clear information of the toxic endpoint of PFOA, which sheds new light on the risk assessment of PFOA on aquatic organisms.

The \(\Pi \)-operator (Ahlfors–Beurling transform) plays an important role in solving the Beltrami equation. In this paper we define two \(\Pi \)-operators on the n-sphere. The first spherical \(\Pi \)-operator is shown to be an \(L^2\) isometry up to isomorphism. To improve this, with the help of the spectrum of the spherical Dirac operator, the second spherical \(\Pi \) operator is constructed as an isometric \(L^2\) operator over the sphere. Some analogous properties for both \(\Pi \)-operators are also developed. We also study the applications of both spherical \(\Pi \)-operators to the solution of the spherical Beltrami equations.