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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.

Molecular interactions between terpenoid mosquito repellents and three typical human-secreted attractants, ammonia, 1-octen-3-ol, and formic acid were studied. Relative energies, bond distances, and bond angles of the molecular interactions were obtained at HF level to evaluate the interaction intensity and types. The effects of molecular interactions on repellency were investigated by the subsequent quantitative structure-activity relationship (QSAR) study. The results of this study suggest that attractant-repellent interaction should not be ignored and could be helpful for future research on the repelling mechanism of mosquito repellents.

In a continuing effort to develop novel natural product-based insecticidal agents endowed with low mammalian toxicity, two series of rosin-based diamides have been synthesized, and their insecticidal activities against Plutella xylostella and Mythimna separata were evaluated. Most of the synthesized compounds exhibited moderate to significant insecticidal activity. Among them, thiadiazole-containing diamides 6a–n displayed better activity than others, especially compounds 6f and 6n which exhibited excellent insecticidal activity against P. xylostella, with LC50 values of 0.223 and 0.214 mg L−1, respectively, which approximate to, or are lower than that of, the control flubendiamide (0.222 mg L−1). The preliminary structure–activity relationship analysis indicated that rosin-based diamides with electron-withdrawing groups on the benzene ring showed better insecticidal activity than those with electron-donating groups. Via a best multilinear regression analysis, the generated quantitative structure–activity relationship (QSAR) model (R2 = 0.9566) revealed a strong correlation of insecticidal activity against P. xylostella with molecular structures of these compounds. These consequences can be expected to instruct the design and development of new rosin-based insecticides.

Interactions between low-toxicity terpenoid mosquito repellents and lactic acid are studied at the HF and B3LYP level. The subsequent QSAR study shows that not only the structure of repellents but also the repellent–lactic acid complexes may play an important role. It suggests that further study on interactions between repellents and characteristic compounds from human host may be required in order to understand the repelling mechanism.

A series of novel unsymmetrically disubstituted acylthioureas fused with hydrophenanthrene structure were synthesized from Δ8-dihydroabietic and dehydroabietic acid, respectively. Their structures were characterized by IR, 1H-, and 13C-NMR spectroscopy. The antitumor activities of the title compounds against SMMC7721 and A549 tumor cells were evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) method. The results showed that three compounds (4c1, 4d1, and 4d2) exhibited highly effective activities against SMMC7721 and A549 cells, their IC50 values are between 1.87–12.67 μM for SMMC7721 cells and 2.20–6.79 μM for A549 cells, respectively. Structure–activity relationship indicating that acylthioureas that furan group fused with Δ8-dihydroabietyl group, trihydroxymethyl fused with Δ8-dihydroabietyl and dehydroabietyl could generate enhance activities of this kind of compounds against SMMC7721 and A549 cells.

The structure of (±)-2-[(1S,3S)-3-acetyl-2,2-dimethylcyclobutyl]-N-(p-tolyl)acetamide has been determined by single crystal X-ray diffraction analysis. The crystal belongs to triclinic system, space group P-1, a = 8.8700(18) A, b = 10.331(2) A, c = 10.363(2) A, α = 71.11(3)°, β = 65.06(3)°, γ = 72.18(3)°, V = 798.6(3) A3, Z = 2, formula unit C17H23NO2. The title compound has a fragment of 2,2-dimethylcyclo-butane and its conformation represents semi-chair. The intermolecular hydrogen bonds N-H...O and C-H...O are revealed.

Mesoporous nanocrystalline tetragonal zirconias were successfully synthesized through a hydrothermal method using a novel bioresource-derived quaternary ammonium salt, dehydroabietyltrimethyl ammonium bromine (DTAB), as a templating agent. The templating agent provides a surface area (242.02 m2/g), high pore volume (0.53 cm3/g), and large average pore diameter (7.65 nm), which suggests that DTAB is a good candidate for mesostructure synthesis. The hydrothermal treatments give the materials improved thermal stabilities because of the generation of tetragonal nanocrystallites that are more stable than the bulk amorphous ones in the hydrothermal process. However, because of the absence of stabilizers, the sizes of the crystallites of the as-synthesized sample increase gradually with increasing calcination temperature. As the crystalline size of the sample rises to 25 nm, the nanocrystallites become too large to integrate well together, causing the well-organized mesostructure to collapse.

A new class of low-toxicity mosquito repellents is synthesized from α- and β-pinene in terpenoid compounds and preliminary biological tests show promising mosquito repellency. Statistical modeling is built using Codessa in order to reveal the quantitative relationship between the structure and the biological activity and to provide the guidance for further synthetic work.

The title compound, C17H23NO2, contains two chiral centres and was synthesized from 2-(3-acetyl-2,2-dimethylcyclobutyl)acetic acid and m-toluidine. The cyclobutane ring is not flat but flexed as though folded from the dimethyl-substituted C atom to the unsubstituted C atom, with a dihedral angle of 25.9°. The crystal structure is stabilized by N—H...O and C—H...O hydrogen-bonding interactions.

The title compound {systematic name: 1-[(1R,4aS,10aR)-7-isopropyl-1,2,3,4,4a,9,10,10a-octa-hydro-phenanthren-1-yl]-N-[(E)-2-pyridylmethyleneamino]methanamine}, C(26)H(33)N(2), has been synthesized from dehydro-abietylamine. The two cyclo-hexane rings form a trans ring junction with classic chair and half-chair conformations, respectively, whereas the benzene and pyridine rings are almost planar, and the dihedral angle between them is 80.4°. The two methyl groups directly attached to the tricyclic nucleus are on the same side of the tricyclic hydro-phenanthrene structure.