The structure of vinerine and vineridine
Summary1. The epigeal part ofV. erecta gathered in the Tashkent Oblast in the early vegetation period contains a mixture of alkaloids (2.7%). Separation of the total alkaloids gave vincanine, vincanidine, vinervine, akuammine, kopsinine, pseudokopsinine, and the new bases vinerine and vineridine.2. The structure of vinerine has been established by a study of the IR, NMR, and mass spectra. Vineridine is isomeric with vinerine at C3 and C7.3. A new base, hydroxyindole reserpinine, has been obtained from reserpinine.
THE STRUCTURE AND STEREOISOMERISM OF THREE MITRAGYNA ALKALOIDS
Isorhyncophylline, the isomer into which rhyncophylline is convertible, has been found to occur in nature. Both bases are interconvertible. Isorhyncophylline on hydrolysis with dilute hydrochloric acid is converted to an aldehyde reducible to isorhyncophyllol. When the aldehyde is reduced in the Wolff–Kishner reaction, it is also isomerized and the product is isorhyncophyllane. This reduction product is oxidized by mercuric acetate to a neutral dilactam which still contains the oxindole carbonyl and further contains a new lactam carbonyl present in a six-membered ring. Reduction of the dilactam with lithium aluminum hydride gave a product having the spectroscopic properties of an indole. This confirms the assumption previously made that in rhyncophylline, ring C is five-membered. The isomerization of rhyncophylline, mitraphylline, and formosanine is described. Formosanine has been shown to be identical with uncarine-B and thus uncarine-A is the iso base derivable from formosanine.
Rapid determination of the effectiveness of insect resistant packaging
A technique was developed to evaluate the usefulness of odour barriers and to determine the effect of package content in consumer size packages on resistance to infestation by insects. Female Plodia interpunctella (Hubner) could distinguish sealed packets containing food from non-food items as a suitable site for oviposition. Utilization ofthis technique will reduce the time needed to evaluate new materials for use in insect resistant packaging.