18720-30-4Relevant articles and documents
Azodioxide radical cations
Greer, Melinda L.,Sarker, Haripada,Mendicino, Maria E.,Blackstock, Silas C.
, p. 10460 - 10467 (1995)
This report provides the first examples of solution-stable azodioxide radical cations and describes their direct spectroscopic observation and, in one case, their thermal chemistry. The formal oxidation potentials, Eo′, for N,N′-dioxo-2,3-diazabicyclo[2.2.2]oct-2-ene (3), N,N′-dioxo-2,3-diazabicyclo[2.2.1]hept-2-ene (4), and N,N′-dioxo-1,1′-azobis(norbornane) (5) are 1.65, 1.68, and 1.54 V vs SCE, respectively. ESR spectroscopy shows the intermediate cations to be π radicals. Radical cation 5?+ (red, λm 510 nm) has a five-line ESR spectrum of a(2N) 1.1 G, while 3?+ (bronze) has a nine-line ESR spectrum simulated as a(4H) 0.86 and a(2N) 1.22 G. Both 3?+ and 5?+ decay in seconds to minutes at room temperature. Thermal decomposition of 5?+ results in C,N and N,N bond cleavage, yielding 1-norbornyl cation (trapped by solvent) and NO+ (trapped in low yield by the oxidant under chemical oxidation conditions). Two viable mechanisms are presented for 5?+'s thermal decay, both of which invoke nitrosoalkane monomer 5m as an intermediate. In a related study, oxidation of nitrosoalkane 2m is found to mediate its facile denitrosation. This work affords the first examples of electron-transfer-mediated C,N bond cleavage of azodioxides and of nitrosoalkanes. Substantial bond weakening is shown to accompany electron loss from these substrates. For 5, π oxidation leads ultimately to σ C,N bond activation.
1-Norbornyllithium as a precursor for the synthesis of novel organic 1-bicyclo[2.2.1]heptane derivatives and for the improved preparation of 1-chloro-bicyclo[2.2.2]octane
Kostova,Dimitrov
, p. 1575 - 1587 (1995)
An improved strategy for synthesis of 1-chloro-bicyclo[2.2.2]octane is described in which the key compounds 1-norbornyl substituted ethyl formate or 1-norbornylcarbaldehyde were prepared from 1-norbornyllithium. The latter appeared as a useful precursor for the synthesis of various organic bridgehead substituted derivatives.
DERMATOLOGICAL COMPOSITIONS AND METHODS
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, (2008/06/13)
Disclosed are methods and compositions for regulating the melanin content of mammalian melanocytes; regulating pigmentation in mammalian skin, hair, wool or fur; treating or preventing various skin and proliferative disorders; by administration of various compounds, including alcohols, diols and/or triols and their analogues.
Treatment of diseases mediated by the nitric oxide/cGMP/protein kinase G pathway
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, (2008/06/13)
Disclosed are methods and compositions for stimulating cellular nitric oxide (NO) synthesis, cyclic guanosine monophosphate levels (cGMP), and protein kinase G (PKG) activity for purposes of treating diseases mediated by deficiencies in the NO/cGMP/PKG signal transduction pathway, by administration of various compounds including alcohols, diols and/or triols and their analogues.
