The structure of regalamine
SummaryOn the basis of UV, IR, NMR, and mass spectra and chemical transformations the structure of 11,12-dihydroxy-2-methoxy-1,12-epoxyhexahydrohomoproaporphine has been proposed for regalamine.
Alkaloids from croton species. VI. Mass spectrometric studies of the crotonosine alkaloids.
The mass spectra of crotonosine and some related compounds are reported and the composition of the major fragments determined by high-resolution mass measurements. Modes of fragmentation are discussed. In addition the mass spectra of the model compound tetrahydroisoquinoline and its N-methyl and N-acetyl derivatives are reported and discussed.
Totalsynthese und absolute Konfiguration von natürlichem Multifloramin
The diphenol 1 was resolved into its antipodes and their absolute configuration was established. The levorotatory isomer R-(−)-1 was oxidized to the dienone R-(−)-6, which was rearranged to afford natural (−)-multifloramine (R-(−)-7), thus establishing that the latter has the R-configuration. By the same reaction sequences, the enantiomeric diphenol S-(+)-1 was transformed to provide (+)-multifloramine (S-(+)-7) of the S-configuration.