−− The kinetics of the gas-phase isomerization of β-pinene over an acid-activated bentonite clay has been investigated in a fixed-bed continuous flow reactor, at atmospheric pressure between 58 and 90 C. The major isomers produced were camphene, α-pinene and limonene. The reaction rates of β-pinene conversion and the apparent activation energy were determined. The kinetics of β-pinene isomeriza...

Sampling of monoterpenes from air on the Tenax porous polymer may introduce analytical errors owing to oxidation and acid rearrangements on the adsorbent. Particularly terpenes which react rapidly with ozone, e.g. myrcene and limonene, are partially lost when sampling air with high photooxidant levels. On acidified adsorption cartridges, a-pinene and ~-pinene may be converted to camphene, limon...

Exhaustive hydro-distillation of the leaves of Piper aduncum and fruits of Piper gibbilimbum (Piperaceae) afforded colorless and pale orange colored oils in 0.35 and 0.30 % yields, respectively. Detailed chemical analysis by GC/MS indicated the volatile constituents of Piper aduncum to be composed of dill apiole (43.3%), beta-caryophyllene (8.2%), piperitione (6.7%) and alpha-humulene (5.1%), w...

A new bicyclic sulfonamide derivative, N-(1-(bromomethyl)-7,7-dimethylbicyclo[2.2.1]heptan-2-yl)benzenesulfonamide, was synthesized in the reaction of benzenesulfonamide and camphene presence N-bromosuccinimide acetonitrile. The proposed mechanism investigated involves Wagner–Meerwein rearrangement stage. 3-(Bromomethylene)-2,2-dimethylbicyclo[2.2.1]heptane isolated as a minor product. products...

Samples of sage leaves, Salvia triloba (Labiatae), growing ~ ~ i l d in different regions of Greece ere analjzed to determine the essential oil content and the physicochemical consram of the oil. The qualitari~le and quantitati~~e ana/ysis by gas-liquid-chron~atograp h ~ . s h o ~ ~ s variations in the qualitjb of the oils and in the amounts of their components. In all samples the basic compone...

The essence oil from the fresh rhizomes of Kaempferia rotunda L. was isolated by water distillation and analyzed by gas chromatography-mass spectrometry (GC/MS) method. Fifty seven components were identified in the rhizomes oil, which accounted to 99.74% of the oil. The major components were endo-borneol (9.30%), dehydro iso androsterone acetate (9.12%), naphthalene, decahydro-1,1,4a-trimethyl-...

The essential oil composition of Rhus cotinus L. (syn. Cotinus coggygria Scop.; Family: Anacardiaceae), was analyzed by GC and GC-MS. The in vitro antioxidant activity was assessed by β-carotene bleaching test, reducing power, DPPH radical scavenging and inhibition of lipid peroxidation methods. A total of 30 compounds were identified with the dominance of monoterpenes (65.9%) viz. β-Pinene, ca...