Sinomeninone furazan

Further degradation of 1-bromosinomeninone furazan methine yields l-bromo-9 10-dehydro-(—)-thebenone ketone furazan, which cannot be prepared by the bromination of [Lxxxvm] as this reaction gives the isomeric 9 -bromo-derivative. The Hofmann degradation of 1 9 -dibromosinomeninone furazan methine and the bromination of [Lxxxvm] and its 1- and 9 -bromo-derivatives all yield, finally, 1 9 -dibromo-9 10-dehydro-(—)-thebenone ketone furazan. l-Bromo-(—)-thebenone ketone furazan may be prepared either by the bromination of [lxxxix] or by the bromination of sinomeninone furazan dihydro-methine, followed by the degradation of the resulting 1-bromo-deriva-tive [51-52]. 

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