In the title compound, C(20)H(20)N(2), the quinoxaline ring adopts a very distorted half-chair conformation [N=C-C=N = 22.7 (2)° for the nominally coplanar atoms] and the cyclo-hexane ring adopts a chair conformation. The quinoxaline and cyclo-hexane rings are cis-fused. The two phenyl rings form a dihedral angle of 63.88 (7)°.

In the title compound, C(8)H(12)O(2), the cyclo-hexane ring exhibits a chair conformation and the δ-lactone ring is axially bonded to the cyclo-hexane ring. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, resulting in ribbons extending along [010].

The hexane extract of the flowers of Rheum ribes L. which was collected from north-western Iran,was obtained by Soxhlet apparatus and the essential oil composition was obtained by hydro distillationand analyzed by using GC-GC/MS. The extract from the flowers was characterized by a high amountof unsaturated fatty acids (UFA) (66.0%) and some of long chain hydrocarbon compounds. The maincomponent...

The removal of volatile organic compounds (VOC) in biofilters packed with organic filter beds, such as peat moss (PM) and pine sawdust (PS), frequently presents drawbacks associated to the collapse of internal structures affecting the long-term operation. Poly(ethylene ether carbonate) (PEEC) groups grafted to these organic carriers cross linked with 4,4'-methylenebis(phenylisocyanate) (MDI) pe...

hexane was shaken with 2 ml. of boron trifluoride etherate, BF3 + (C2H6)20 (b.-p. 124-126°), at room temperature. The dark blue complex was decomposed by the addition of 100-200 ml. of 95% methanol, then transferred with water into hexane. The hypophase was discarded and the epiphase washed, dried, adsorbed on a suitable lime-celite column (2:1) and developed with hexane. The respective zones w...

The carcinogenic and chronic toxicity potential of commercial hexane solvent was evaluated in F-344 rats and B6C3F1 mice (50/sex/concentration/species) exposed by inhalation for 6 h/day, 5 days/week for 2 years. Target hexane vapor concentrations were 0, 900, 3000, and 9000 ppm. There were no significant differences in survivorship between control and hexane-exposed groups, and clinical observa...

A sensitive method was developed for determination of n-hexane and cyclohexane in human body fluids by headspace capillary gas chromatography (GC) with cryogenic oven trapping. Whole blood and urine samples containing n-hexane and cyclohexane were heated in a 7.5 mL vial at 70 degrees C for 15 min, and 5 mL of the headspace vapor was drawn into a glass syringe. All vapor was introduced through ...

the dried plant was extracted with dichloromethane and after defatting with hexane, transferred repeatedly on silica columns using dichloromethane-hexane and ethyl acetate-hexane as mobile phases. finally the fractions were purified by high performance liquid chromatography using a pack-sil column and hexane: ethyl acetate as mobile phase. the structures of the isolated compounds included: cycl...

in this study, both the presence and concentration of some unsaturated compounds in hexane extracts of different parts of anthemis talyschensis showing absorption at wavelength 280-450 nm were surveyed, with the view of possibly using extracts of this plant in new formulations of sunscreen creams. the hexane extracts of flower, leaf and stem of a. talyschensis , collected from northwest iran, w...