| Selenium compounds with potent anticancer activity have been under review for many years. Several selenoamino acids have been used for suppression of tumor development in rodents. A previously unreported selenoamino acid, S-(methylseleno)-cysteine, having a Se-S bond was synthesized and confirmed as a natural product of selenized yeast. The natural product was shown to be different from the synthetic sample of the isomeric compound Se-(methylthio)selenocysteine.;Isolation, characterization, and synthetic studies of sulfur-containing peptides of Marasmius alliaceus (garlic Marasmius ) and shiitake mushrooms were performed. Further information regarding their structure was obtained. The degradation process for the formation of the volatile substances previously identified in the mushroom was also studied. A novel regioselective oxidation method was used and provided an efficient route for the synthesis of marasmine. |
