Irradiation of an acetone solution of cis-6,7,8-trideoxy-l,2:3,4-di-O-isopropylidene-7-C-nitro-~-~-galacto-oct-6-enose (4) with ultraviolet light gives a complex mixture from which the three major products have been isolated: the trans isomer of the nitroolefin 4, cis-6,8-dideoxy-1,2:3,4-di-0-isopropylidene-a-Dgalacto-oct-5-enos-7-ulose (5), and the trans isomer of 5. The structures of the compounds were established by spectroscopic methods. Signal assignments in the nuclear magnetic resonance spectra have been made by spin decoupling.
The effect of heat (1 hour at 110°C) on a range of solid metal salts of humulone has been examined. Some salts, e.g. those of calcium, magnesium, cobalt (II) and nickel (II) undergo isomerization to the corresponding salt of isohumulone without any significant degradation. Other metal salts undergo partial isomerization without apparent degradation and some form both isohumulone and uncharacterized degradation products. The salts of aluminium, chromium (III), copper (II), lead (II) and mercury (II) show no formation of isohumulone. Under the same conditions the lead (II) salt of tsohumulone was unique in converting completely into the lead (II) salt of humulone.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.