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Biogenic volatile organic compounds (bVOCs), synthesised by plants, are important mediators of ecological interactions that can also undergo a series of reactions in the atmosphere. Ground-level ozone is a secondary pollutant generated through sunlight-driven reactions between nitrogen oxides (NOx) and VOCs. Its levels have increased since the industrial revolution and reactions involving ozone drive many chemical processes in the troposphere. While ozone precursors often originate in urban areas, winds may carry these hundreds of kilometres, causing ozone formation to also occur in less populated rural regions. Under elevated ozone conditions, ozonolysis of bVOCs can result in quantitative and qualitative changes in the gas phase, reducing the concentrations of certain bVOCs and resulting in the formation of other compounds. Such changes can result in disruption of bVOC-mediated behavioural or ecological interactions. Through a series of gas-phase experiments using Gas Chromatography Mass Spectrometry (GC-MS) and Proton Transfer Reaction Mass Spectrometry (PTR-MS), we investigated the products and their yields from the ozonolysis of a range of ubiquitous bVOCs, which were selected because of their importance in mediating ecological interactions such as pollinator and natural enemy attraction and plant-to-plant communication, namely: (E)-β-ocimene, isomers of α and β-farnesene, α-terpinene and 6-methyl-5-hepten-2-one. New products from the ozonolysis of these compounds were identified, and the formation of these compounds is consistent with terpene-ozone oxidation mechanisms. We present the degradation mechanism of our model bVOCs and identify their reaction products. We discuss the potential ecological implications of the degradation of each bVOC and of the formation of reaction products. [ABSTRACT FROM AUTHOR]

3-Carene, α-pinene, and limonene α-(dimethylamino)oximes were converted to glycidyl ethers at the oxime hydroxyl. The compounds obtained were involved in the reactions with amines, imidazole, as well as with anions of these dimethylamino oximes. The glycidyl ether epoxide ring opening by amines under microwave irradiation conditions proceeds considerably faster than upon convection heating. [ABSTRACT FROM AUTHOR]

Rabdoternin A is a natural diterpenoid isolated from Rabdosia rubescen and its crystal structure was determined by X-ray single crystal diffraction. The compound compactly packs in an orthorhombic unit cell in the P222 space group with unit cell dimensions a = 7.9200(10) Å, b = 11.2411(14) Å, c = 20.474(2) Å, V = 1822.8(4) Å and Z = 4. Two intermolecular hydrogen bonds assemble the title compound into infinite two-dimensional networks along (001) plane. Graphical Abstract: Rabdoternin A is a natural diterpenoid isolated from Rabdosia rubescen and its crystal structure was determined by X-ray single crystal diffraction. The compound is built up from five-six-membered rings and one-five-membered ring, intermolecular hydrogen bonds assemble the title compound into infinite two-dimensional networks along (001) plane.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The review discusses recent advances in the field of acid-catalyzed intra- and intermolecular transformations of pinane terpenoids and their oxygen-containing derivatives. [ABSTRACT FROM AUTHOR]