The objective of this study is to evaluate the influence of different chemical surface treatments (H 3 PO 4 , HNO 3 , and NaOH) in the formation of calcium phosphate phases on the surface of Al 2 O 3 /ZrO 2 (5 vol%) nanocomposite. For this purpose, Al 2 O 3 /ZrO 2 samples were shaped, calcined at 400°C, sintered at 1500°C, subjected to different chemical treatments, and biomimetically coated from 14 to 21 days. Surface characterization was performed by scanning electron microscopy, atomic force microscopy, confocal microscopy, X-ray diffraction, and infrared spectroscopy. It was observed that the preliminary chemical treatment favored the formation of particular calcium phosphate phases of interest, such as α-TCP (alpha-tricalcium phosphate), β-TCP (betatricalcium phosphate), and HA (hydroxyapatite). The differences among the percentages of the phases formed affected the homogeneity of calcium phosphate distribution within the nanocomposites as well as the roughness of the formed layer, effectively contributing to adhesion, proliferation, and desired cell biofixation on bone implant.

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Complexation-induced chemical shifts and diffusion coefficients (HR-DOSY) of enantiomers with native and derivatized cyclodextrins were used for calculations of the apparent binding constants of three cyclohexanone inclusion complexes. Correlations between these data and high-performance liquid chromatography were established, revealing that this approach can be applied as an alternative method to predict enantiomeric discrimination.

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Treatment of 8-oxabicyclo[3.2.1]oct-6-en-3-one with a catalytic amount of osmium tetraoxide and excess hydrogen peroxide resulted in the formation of the acetonide exo-6,exo-7-isopropylidenedioxy-8-oxabicyclo[3.2.1]oct-3-one (2), in 96% yield. This acetonide was converted into several aromatic alcohols (4a–k) through a Grignard reaction. The alcohols were treated with aqueous HCl in acetone, and the corresponding alkenes (5a–c,e–g, j,k) were obtained in 26–46% overall yield, from the ketone (2). The herbicidal activity of the alkenes was evaluated at a concentration of 6.6 µg g−1. All compounds showed an inhibitory effect (21–66%) on the Sorghum bicolor radicle growth. The inhibition of the accumulation of fresh and dried weight of the aerial parts of Cucumis sativus, after 14 days, varied from 7.1 to 60.7% and from 0.0 to 41.6%, respectively. Compounds (5a,e–g) caused 100% mortality of C. sativus, after 20 days. Compound (5g) (exo-6,exo-7-isopropylidenedioxy-3-(3-methylphenyl)-8- oxabicyclo[3.2.1]oct-2-ene) was evaluated against several weeds, and it caused 100% mortality of Desmodium tortuosum and Pennisetum setosum.