No abstract

A set of 8‐arylxanthines was prepared under metal‐free conditions and in aqueous solvents from arylazo sulfones and caffeine or theophylline. Notably, the process took place by simply exposing the reaction vessel to visible or solar light, and unreacted xanthine could be easily recovered during the purification step.

A versatile protocol for the diazenylation of enol silyl ethers under visible light irradiation is presented herein. The reaction is based on the underused reaction of a nitrogen-based radical (the diazenyl radical) with an enol silyl ether. Arylazo sulfones were used as photoactivatable precursors of these diazenyl radicals. The resulting azaderivatives are potentially bioactive compounds as well as starting materials for the synthesis of N-containing heterocycles.

The hydrogen peroxide oxidation of 4-tert-butyltoluene to 4-tert-butylbenzaldhyde, an important fragrance intermediate, catalyzed by cobalt acetate and bromide in acetic acid was investigated again. The initial stages of the reaction appear to be rapid and quantitative, but after approximately 25−30% conversion, the process ceases. Overoxidation to 4-tert-butylbenzoic acid does not occur. It appears that both water and the aldehyde product itself inhibit further oxidation. An engineering solution to remove the product continuously seems required for process optimization.

Hydrodeaminated and monodeuterated aromatics were obtained via a visible-light driven reaction of arylazo sulfones. Deuteration occurs efficiently in deuterated media such as isopropanol-d8 or in THF-d8/water mixtures and exhibits a high tolerance to the nature and the position of the aromatic substituents.

Essential oils obtained by hydrodistillation of different parts of Iris persica L. were investigated for the first time by GC-FID and GC-MS; moreover, their antifungal activities were determined. 34, 32, 27, and 17 compounds were identified in the oils from air-dried flowers, leaves, rhizomes and fresh bulbs, respectively, representing ≥ 98% each oil. The major constituents of the flower essential oil were phenylethanol (24.8%) and furfural (13.8%), which, as the main component, constituted also 39.0% and 22.2% of the leaf and rhizome volatile fractions, respectively. Phenylacetaldehyde (37.1%) was the main constituent of the bulb volatile fraction. In in vitro tests, moderate antifungal activity was detected for the oils against strains of the human pathogenic fungal species Candida albicans, Microsporum canis, and Trichophyton mentagrophytes, the plant-fungal pathogen Pyricularia oryzae, and the fungal food contaminant Aspergillus carbonarius,. The highest activity was exhibited by the essential oils from leaves and flowers, suggesting that they could be considered natural antimicrobial agents.

The coast of Southeast Indian and the tropical part of the Western Pacific is a habitat for the tropical sea grass Enhalus acoroides. In Ekas Bay, East Lombok, E. acoroides grows well in seashores, which is important to tropical marine ecosystem. Previous research reported the pharmacological activity of E. acoroides such as antioxidant and antibacterial. E. acoroides was tested to identify their secondary metabolites using phytochemical screening. The secondary metabolites were further characterized using thin layer chromatography with specific spray reagent. The phytochemical screening identified primary metabolites such as carbohydrates and proteins. On the other hand, the phytochemical screening also detected secondary metabolites such as alkaloid, phenolic, tannin, saponins, flavonoid, monoterpenes, and sesquiterpenes. The TLC profile with specific spray reagent confirmed the bioactive components such as phenolic, flavonoid, and terpenes in methanol extract of E. acoroides. These results had a significant impact on profiling the marine plant as a new drug candidate. The information of secondary metabolites from E. acoroides will contribute to further research in determination of antioxidant, and antibacterial activity of E. acoroides, as a promising marine drug candidate from Indonesia.

5-Hydroxy-isoxazolidinic heterocycles can be easily prepared from hydroxamic acids and suitable ,unsaturated aldehydes or ketones in good yields from solid state synthesis, selectively promoted by DEAE-C. The synthesized products were efficiently derivatized with representative heterobases for the preparation of nucleoside analogues suitable for biological evaluation and SAR analysis.