Gas chromatographic resolution of (±)-menthone via its (+)-tartaric acid derivatives

Stereoselective radical reactions of some tartaric and glyceric acid derivatives.

[reaction: see text] Free radicals generated by the decarboxylation of dimethoxydioxanecarboxylic acids derived from L-(+)-tartaric acid and L-glyceric acid added to some maleimides and acrylates with high stereoselectivity. This method provides easy access to some chiral building blocks.

Gas-chromatographic detection of phthalic acid esters.

Each second, the rivers of the world add 109 kg of fresh water to the oceans, and with this water comes tremendous quantities of salts, clay minerals, and other suspended solids. Although the Amazon River makes the largest contribution of fresh water to the sea, its waters are relatively uncontaminated. On the other hand, the Mississippi River, the third largest river, which delivers only about...

Gas chromatographic behavior of fatty acid derivatives for mass spectrometry on low-polarity capillary columns

The gas chromatographic properties of four derivatives of fatty acids (FA), namely fatty acid methyl esters, picolinyl esters, N-acyl pyrrolidides and 4,4-dimethyloxazoline derivatives, which contain various structural features (double bonds, branching, hydroxyl group) in their acyl chains have been compared on a low-polarity capillary column with a mass spectrometer as detector. Temperature pr...

Significance of urinary tartaric acid.

Gas-liquid chromatographic procedure for measurement of methylphenidate hydrochloride and its metabolite, ritalinic acid, in urine.

A gas-liquid chromatographic procedure has been developed for measuring methyiphenidate and its metabolite, ritalinic acid, in urine. The unchanged drug is extracted into chloroform from alkalinized urine together with an internal standard, diphenhydramine. The solvent is removed, the residue dissolved in ethanol, and aliquots are injected into a gas-chromatographic Column containing 3% OV-1 7....