Thermal decomposition of propoxyphene during GLC analysis.

The decomposition products of propoxyphene during GLC were prepared on a larger scale by heating propoxyphene hydrochloride in the presence of glass wook. They were identified by mass spectrometry and NMR spectroscopy as two isomeric diphenylbutenes and two isomeric products formed by loss of propionic acid. On-column decomposition of proxyphene can be prevented by injection of the compound in solution in a silylating agent.

Determination of dextro- and levomethorphan mixtures using chiral lanthanide NMR shift reagents.

Europium and praseodymium chiral NMR shift reagents were used to differentiate between dextro- and leveomethorphan. The enantiomeric shift differences (delta delta delta) demonstrated by the singlet associated with the methoxy protons were large enough to identify the levo- and dextro-isomers and to allow for the determination of as little as 10% of one enantiomer in the presence of the other in a prepared mixture. The analytical method is rapid and can analyze samples as small as 1 mg.

Proton magnetic resonance spectroscopic determination of disulfiram: collaborative study.

A proton magnetic resonance spectroscopic method for determining disulfiram in the bulk drug product and in the formulated material was collaboratively studied. The method depends on the use of chloroform-d as a solvent and hexamethylcyclotrisiloxane as the internal standard. No interference from tablet excipients was observed. The method is rapid and specific. Eighteen laboratories analyzed duplicate samples of a bulk drug product, a 250 mg tablet composite, and a 500 mg tablet composite. The average per cent results and standard deviations were 99.7 +/- 1.4, 100.9 +/- 2.0, and 99.9 +/- 2.2, respectively.

Mandelonitrile beta-glucuronide: synthesis and characterization.

Mandelonitrile beta-glucuronide, the compound patented as Laetrile, has been synthesized from rabbit liver uridine diphosphate-glucuronosyl transferase immobilized on beaded sepharose, has been analyzed by thin-layer chromatography, nuclear magnetic resonance, and gas chromatography-mass spectrometry, and has been tested for cytotoxicity and mutagenic activity with Salmonella typhimurium strains TA 98 and TA 100. Several commercial laetrile preparations contained no glucuronide; they contained amygdalin and neoamygdalin instead. Mandelonitrile, mandelonitrile glucuronide, and a mixture of amygdalin and neoamygdalin were each found to be mutagenic.

Determination of methyl methacrylate in surgical acrylic cement.

A methyl methacrylate cement used in hip surgery as well as in dentistry was identified and quantitatively analyzed for its monomer content in starting materials and in the finished cement by proton magnetic resonance spectroscopy. IR data indicated that the monomer continued to escape from the product after it had hardened. The presence of 21% methyl methacrylate monomer relative to the polymer was demonstrated at the time the cement normally would be inserted into the body.

The analysis of pharmaceuticals by combined gas chromatography-mass spectrometry. I. The analysis of a medicated aerosol spray.

A medicated aerosol product was qualitatively analyzed by combined gas chromatography-mass spectrometry. The data were processed by a minicomputer. Ten of the 11 peaks in the gas chromatogram were identified with the assistance of the National Institutes of Health/Division of Computer Research and Technology/Chemical Information System mass spectral search system. The unidentified peak is probably a member of the terpene class. The aerosol propellants were also partially analyzed by infrared spectrophotometry.