Evaluation of alkene isomerization as a trigger for enediyne activation
作者:M.F. Semmelhack、Richmond Sarpong、Jeffrey Bergman、Douglas M. Ho
DOI:10.1016/s0040-4039(01)02139-6
日期:2002.1
non-conjugated-to-conjugated double bond isomerization as a triggering mechanism for a calicheamicin model was tested. A bicyclo[7.3.1] enediyne framework was prepared with a bridgehead double bond and an acetonyl side chain. Base-promoted exchange failed to produce the conjugated isomer. Computational analysis suggested that additional conjugating groups would favor the isomerization, but experiment proved that
Spezifisch ???*-induzierte Reaktionen von ?-Dimethoxymethylcyclohexen-2-onen: 1,3-Umlagerung und Wasserstoffabstraktion durch das ?-Kohlenstoffatom
作者:Jean Gloor、Kurt Schaffner
DOI:10.1002/hlca.19740570631
日期:——
When α,β-unsaturated γ-dimethoxymethyl cyclohexenones are excited to the S2(π,π*) state, certain unimolecular reactions can be observed to compete with S2 S1 internal conversion. These reactions do not occur from the S1(n,π*) or the lowest T(π,π* and n,π*) states. They comprise the radical elimination of the formylacetal substituent (cf. 8, 9 32 + 33), γ α formylacetal migration (cf. 6 27, 8 30, 9