Ronald G. Smith

Polyamine levels in normal human serum. Comparison of analytical methods.

Abstract A comparison of levels of the polyamines, putrescine, spermidine and spermine, in individual and pooled normal human serum, as determined by three independent methods, high pressure cation-exchange chromatography (HPCC), radioimmunoassay (RIA) and gas chromatography-mass spectrometry (GC-MS), has been made. Generally good correlations were found for values derived by the three different methods.

Sex pheromone of the European pine shoot moth: Chemical identification and field tests

The sex pheromone of the European pine shoot moth, Rhyacionia buoliana, has been isolated and, using chemical methods, its structure shown to be (E)-9-dodecenyl acetate. Field traps containing the synthetic pheromone were consistently more attractive than traps baited with unmated females.

Evidence for the Epoxide‐Diol Pathway in the Biotransformation of Mephenytoin

Summary: A dihydrodiol metabolite of mephenytoin (5‐dihydroxy‐cyclohexadienyl)‐5‐ethyl‐3‐methylhydantoin and other mono‐ and dihydrox‐ylated and N‐demethylated metabolites were identified in urine from a male epileptic patient receiving therapy with mephenytoin (300 mg/day). Metabolites, extracted from urine before and after enzymatic hydrolysis, were de‐rivatized with a trimethylsilyl reagent and analyzed by combined gas chromatography and mass spectrometry. Two previously unreported metabolites were characterized: 5‐ethyl‐5‐(di‐hydroxyphenyl)‐3‐methylhydantoin and 5‐ethyl‐5‐(hydroxy‐methoxy‐phenyO‐S‐methylhydantoin. The structures of several other metabolites were confirmed: N‐demethylmephenytoin, 5‐ethyl‐5‐hydroxyphenylhydantoin, 5‐ethyl‐5‐hydroxyphenyl‐3‐methylhydantoin and mephenytoin dihyrodiol. The dihydrodiol metabolite was of special interest since it was probably produced via an epoxide intermediate, 5‐(epoxy‐cyclohexadienyl)‐5‐ethyl‐3‐methylhydantoin. Previous reports have demonstrated that epoxides of this structural class are extremely reactive compounds, capable of alkylating biologic macromolecules. Covalent binding of the mephenytoin epoxide to macromolecules may be an important factor in the production of adverse and sometimes fatal side effects observed in patients receiving long‐term therapy with mephenytoin.