Novel Annelated Glycoheterocycles by Photocyclisation

Joachim Thiem

Institut für Organische Chemie, Universität Hamburg, Germany

Various approaches were elaborated to lead to normal as well as 2-deoxy glycosylimides. Norrish-Yang cyclisation could be effected to give α-hydroxy acetidines which in turn rearranged to give sugar-annelated azepindiones. Also δ-abstractions could be observed to give highly functionalised triyclic [5.3.1.0^2,6] ring systems.

Prolonged irradiation gave rise to further intramolecular C-C-bond formation and [5.4.0.0^2,9] ring systems.

Terminally succinimide-substituted saccharide derivatives led to spirocyclic sugar-azepindione components. In contrast, irradiation of the corresponding phthalimides resulted in the formation of completely different oligocyclic structures.