Search

Control of fungal phytopathogens affecting crops and woodlands is an important goal in environmental management and the maintenance of food security. This work describes the synthesis of 37 camphor derivatives, of which 27 were new compounds. Their antifungal effects on six fungi were evaluated in vitro. Compounds 3a, 4a and 5k showed strong antifungal activity against Trametes versicolor, with EC50 values of 0.43, 6.80 and 4.86 mg/L, respectively, which were better than that of tricyclazole (EC50 118.20 mg/L) and close to or better than that of carbendazim (EC50 1.20 mg/L). The most potent compound, 3a, exhibited broad-spectrum antifungal activity towards six fungi with EC50 values within the range of 0.43–40.18 mg/L. Scanning electron microscopy demonstrated that compounds 3a, 4a and 5k gave irregular growth and shriveling of the mycelia. In vitro cytotoxicity evaluation revealed that the tested camphor derivatives had mild or no cytotoxicity for LO2 and HEK293T cell lines. Quantitative structure−activity relationship (QSAR) analysis revealed that the number of F atoms, relative molecular weight, the atomic orbital electronic population and total charge on the positively charged surfaces of the molecules of camphor derivatives have effects on antifungal activity. The present study may provide a theoretical basis for a high-value use of camphor and could be helpful for the development of novel potential antifungals.

Using a mixture of neutral primary amine dehydroabietylamine (DHAA) and long-chain cetyltrimethyl ammonium bromide (CTAB) as the template, ordered lamellar supermicroporous silicas were synthesized with NaOH as the base source and tetraethylorthosilicate (TEOS) as the silica source. The concentrations of DHAA, CTAB, and NaOH in the synthesis system had great effects on the structural properties of the samples. When the molar ratio of components was nTEOS:nCTAB:nDHAA:nNaOH:nH2O = 1:0.114:0.00457:0.5:60, the material showed a lamellar phase with the highest ordering degree. By adding only a trace amount of DHAA into the synthesis system, the structure of the samples could be transformed from cubic phase to lamellar phase, since the added DHAA solubilized in CTAB micelles to change the effective surfactant ion pair packing parameter. The dosage of CTAB should be moderate; too high or too low will decay the ordering degree of the lamellar structure.A much higher concentration of NaOH resulted in an ethanol-rich solvent in which the DHAA did not solubilize in the micelles of CTAB, but adsorbed at the hydrophilic headgroup-solvent interface. Accordingly, a structural transformation from lamellar phase to hexagonal phase occurred.

With the assistance of a rosin-based surfactant, dehydroabietyltrimethyl ammonium bromine (DTAB), well-dispersed hollow cube-like zirconia particles were firstly synthesized by the hydrothermal treatment of ZrOCl2 aqueous solutions. The introduction of DTAB is crucial for improving the dispersion and regularity of the as-synthesized sample. After calcination, the crystal size of the calcined samples increased, and the edge angle of the cube-like particles became round accordingly. Finally, a hollow spherical morphology was formed for the sample calcined at 923 K. The as-synthesized sample showed big surface area of 146.78 m2/g and large pore volume of 0.23 cm3/g. With the increase of calcination temperature, the surface area and pore volume of the samples decreased significantly, and the pore size increased accordingly.

Background: The development of new antifungal agents has always been a hot research topic in pesticide development. In this study, a series of derivatives of natural compound β-pinene were prepared, and the antifungal activities of these derivatives were evaluated. The purpose of this work is to develop some novel molecules as promising new fungicides. Methods: Through a variety of chemical reactions, β-pinene was transformed into a series of β-pinene-based derivatives containing amide moieties and acylthiourea moieties. The antifungal activities of these derivatives against five plant pathogens including Colletotrichum gloeosporioides, Fusarium proliferatum, Alternaria kikuchiana, Phomopsis sp. and Phytophthora capsici were tested; preliminary structure−activity relationship was discussed. Results: Some derivatives exhibited moderate or significant antifungal activity due to the fusion of the amide moiety or the acylthiourea moiety with the pinane skeleton. The structure−activity relationship analysis showed that the fluorine atom and the strong electron withdrawing nitro group, or trifluoromethyl group on the benzene ring of the derivatives had a significant effect on the improvement of the antifungal activity against Colletotrichum gloeosporioides, Fusarium proliferatum, Alternaria kikuchiana and Phomopsis sp. Meanwhile, the introduction of an ethyl group at the meta-position on the benzene ring of the derivatives could improve the antifungal activity against Phytophthora capsici. Compounds 4e, 4h, 4q, 4r exhibited broad-spectrum antifungal activity against the tested strains. Compound 4o had significant antifungal activity against Phytophthora capsici (IC50 = 0.18 μmol/L). These derivatives were expected to be used as precursor molecules for novel pesticide development in further research.

Turpentine is a renewable and resourceful forest product. The deep processing and utilization of turpentine, particularly its primary component β-pinene, has garnered widespread attention. This study aimed to synthesize 40 derivatives of β-pinene, including nopinone, 3-cyanopyridines of nopinone, myrtanyl acid, myrtanyl acylthioureas, and myrtanyl amides. We assessed the antiviral activities of these β-pinene derivatives against influenza virus A/Puerto Rico/8/34 (H1N1) using the 3-(4,5-dimetylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. The β-pinene derivatives were used before and after cellular infection with the influenza virus to evaluate their preventive and therapeutic effects against the H1N1 virus. The results showed that only compound 10o exhibited a preventive effect against the H1N1 virus with a half-maximal inhibitory concentration (IC50) value of 47.6 μmol/L. Among the compounds, 4e, 4i, and 4l demonstrated therapeutic effects against cellular infection, with compound 4e displaying the most potent therapeutic effect (IC50 = 17.5 μmol/L), comparable to the positive control ribavirin. These findings indicated that certain β-pinene derivatives exhibited in vitro antiviral activity against the H1N1 influenza A virus, warranting further investigation as potential anti-influenza agents. [ABSTRACT FROM AUTHOR]

The preparation of bioactive derivatives from the renewable natural product pinene is a hot research topic in the deep processing and utilization of pinene. In this study, β-pinene was used to develop novel molecules as a promising new precursor of insecticide. A series of amide-containing derivatives of β-pinene were synthesized and characterized. The insecticidal activities of these derivatives against Mythimna separate and Semiaphis heraclei were tested. The structure characterization results showed that the characterization data of amide-containing derivatives were in full agreement with their proposed structures. The insecticidal activities evaluation results indicated that amide-containing derivatives exhibited weak insecticidal activity against Mythimna separate, but exhibited moderate to good insecticidal activity against Semiaphis heraclei. After testing for 72 h, the corrected mortality against Semiaphis heraclei of compounds 5c, 5e, 5f, 5 h, 5j, and 5 m was 100% at 1000 mg/L. The structure-activity relationship analysis results showed that the introduction of an amide group into the structure of derivatives improved their insecticidal activity against Semiaphis heraclei. Meanwhile, the amide-containing derivatives containing the F and NO2 substituted benzene ring might improve their insecticidal activity against Semiaphis heraclei. This study will be helpful for the high value-added utilization of the natural renewable resource β-pinene and the development of novel insecticides. [ABSTRACT FROM AUTHOR]

Rationale: Boride compounds hold promise for broad applications in the field of optoelectronics due to their high-temperature resistant, corrosion resistant and antioxidant properties. In order to reveal the formation mechanism of alkali and alkaline earth metal doped boron clusters, theoretical studies of these systems are required. Methods: All the possible geometrical structures of BeBn+ clusters (n = 1-8) were optimized at the B3LYP/6-311+G(d) level; the harmonic vibration frequencies were obtained to examine the true stability and give the zero-point vibration energy at that theoretical level. The single point energies of all the structures were computed at the CCSD(T)/aug-cc-pVDZ level. For the most stable structures, the average binding energy (Eb ), the fragmentation energy (EF ) and second-order difference of total energy (Δ2E) were used to evaluate the relative stability of clusters. Results: Most of the BeBn+ clusters are planar in structure; the B atoms tend to aggregate to form a boron ring, and the coordinating Be atoms are on the periphery of the clusters. The fragmentation energy and second-order difference of total energy show that there is an obvious odd-even alteration as n increases, and local-maxima when n is odd. Conclusions: A systematic theoretical investigation on the geometries, stabilities and electronic properties of BeBn+ clusters has been carried out where n = 1-8. The results provide a useful reference for understanding the formation mechanism and stability of these clusters, as well as guidance for finding larger size clusters. [ABSTRACT FROM AUTHOR]

The development of a novel repellent plays an important role in the integrated control of Blattella germanica. A series of novel hydronopylformamides derivatives were synthesized from a naturally occurring compound (-)-β-pinene. The structures of these hydronopylformamides derivatives were characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (1H-NMR and 13C-NMR), and electron impact mass spectrometry (EI-MS). Repellency of these hydronopylformamides derivatives against Blattella germanica was evaluated by the using petri dish arena method. The results showed that four derivatives (compounds 8a, 8b, 8c and 8e) exhibited repellency against Blattella germanica at a concentration of 20 mg/mL. Compound 8a was the most active compound among these derivatives, where the repelling ratios of compound 8a against Blattella germanica were 66.10%, 50.46%, 48.26%, at concentrations of 20 mg/mL, 10 mg/mL, and 5 mg/mL, respectively. In addition, compound 8a showed better repellency than the traditional insect repellent N, N-diethyl-3-methylbenzamide (DEET), which indicated that compound 8a had a good application prospect in the prevention of Blattella germanica. This research hopes to promote the value-added utilization of (-)-β-pinene and the development of novel German cockroach repellents. [ABSTRACT FROM AUTHOR]

Twelve (+)-nopinone-based 2-amino-3-cyanopyridines 4a—l were synthesized from (—)-β-pinene. The structures of these compounds were characterized by FT-IR, 1H NMR, and ESI-MS. All the compounds were tested for their anticancer activity against lung cancer cell line A549, gastric cancer cell line MKN45 and breast cancer cell line MCF7 by MTT method, respectively. The results showed that compounds 4f, 4j and 4k had promising anticancer activity against these cancer cell lines, in particular, compound 4f exhibited broad-spectrum and highly efficient anticancer activity against cell lines A549, MKN45 and MCF7 with IC50 of 23.78, 67.61 and 53.87 μmol·L-1, respectively. The preliminary analysis of the structure activity relationship implied that the Br or Cl substituted group of the benzene ring in these derivatives significantly contributed to the anticancer activity.