Conversion of Methane into Methanol and Ethanol over Nickel Oxide on Ceria–Zirconia Catalysts in a Single Reactor

The conversion of methane into alcohols under moderate reaction conditions is a promising technology for converting stranded methane reserves into liquids that can be transported in pipelines and upgraded to value‐added chemicals. We demonstrate that a catalyst consisting of small nickel oxide clusters supported on ceria–zirconia (NiO/CZ) can convert methane to methanol and ethanol in a single, steady‐state process at 723 K using O₂ as an abundantly available oxidant. The presence of steam is required to obtain alcohols rather than CO₂ as the product of catalytic combustion. The unusual activity of this catalyst is attributed to the synergy between the small Lewis acidic NiO clusters and the redox‐active CZ support, which also stabilizes the small NiO clusters.     

Physicochemical properties of maize cob cellulose powders reconstituted from ionic liquid solution

Suitable α-cellulose and cellulose II powders for use in the pharmaceutical industry can be derived from maize cob. α-Cellulose was extracted from an agricultural residue (maize cobs) using a non-dissolving method based on inorganic substances. Modification of this α-cellulose was carried out by its dissolution in the ionic liquid 1-butyl-3-methylimidazolium chloride ([C₄mim]Cl), and subsequent regeneration by addition of either water or acetone at room temperature, or of boiling water. X-ray diffraction and infrared spectroscopy results showed that the regenerated celluloses had lower crystallinity, and proved that the treatment with [C₄mim]Cl led to the conversion of the crystalline structure of α-cellulose from cellulose I to cellulose II. Thermogravimetric analysis and differential scanning calorimetry data showed quite similar thermal behavior for all cellulose samples, although with somewhat lower stability for the regenerated celluloses, as expected. The comparison of physicochemical properties of the regenerated celluloses and the native cellulose mainly suggests that the regenerated ones might have better flow properties. For some of the characterizations carried out, it was generally observed that the sample regenerated with boiling water had more similar characteristics to the α-cellulose sample, evidencing an influence of the regeneration strategy on the resulting powder after the ionic liquid treatment.     

18,19-Bisnor-13βH, 14-αh-cheilanthane: a novel degraded tricyclic sesterterpenoid-type hydrocarbon from the athabasca oil sands

The Athabasca oil sand bitumen contains a homologous series of tricyclic terpanes containing 19–30 C atoms per molecule. The structure of the most abundant member, the C₂₃ trycyclane, has now been elucidated.     

Fluorine in medicinal chemistry: A review of anti-cancer agents

In this review those fluorinated compounds which have found a role as anti-cancer agents are summarized. The emphasis is to highlight the important drugs but also to highlight the latest developments on emerging compounds. This has been done as comprehensively as possible with the objective of informing readers of some of the latest developments in this area.     

Three hydroxylated lupeol-based triterpenoid esters isolated from the Eastern Nigeria mistletoe parasitic on Kola acuminata

Column fractionation and purification of an n-hexane fraction led to the isolation of three lupeol-based triterpenoid esters from the leaves of the Eastern Nigeria mistletoe, Loranthus micranthus Linn parasitic on a local kola nut tree, Kola acuminata. These three compounds were adequately characterised using a combination of UV/visible, IR, NMR (13C-NMR and 1H-NMR), DEPT, MS and two-dimensional correlation (H-H COSY, Hetero-nuclear Single Quantum Correlation (HSQC), HMBC, NOE and NOESY) studies as 7β,15α-dihydroxyl-lup-20(29)-ene-3β-esters of palmitic (I), stearic (II) and eicosanoic acids (III). The characterisation of other isolated compounds is ongoing. Remarkably, this is the first report of the existence of fatty acid esters of an unusual 7β,15α-dihydroxylated lupeol in the Eastern Nigeria mistletoe. These isolated compounds might contribute in part to the numerous established bio-activities of the Eastern Nigeria mistletoes.