Syntheses of imido-substituted glycosans and their photocyclisation towards highly functionalised heterotricycles.
Reaction of O-protected amino-1,6-anhydro-beta-D-hexopyranoses with succinic or glutaric anhydride and subsequent intramolecular acylation afforded the succinimido- and glutarimido-substituted glycosans. Irradiation with UV light of 254 nm wavelength led to gamma-hydrogen abstraction at the pyranose ring by the excited carbonyl function. The stereoselective recombination of the resulting 1,4-diradicals gave annelated azetidinols, which fragmented by a retrotransannular ring opening reaction to give the glycosan-annelated azepanedione and azocanedione systems, respectively.
Thiering
S
S
Institut für Organische Chemie, Universität Hamburg, Martin-Luther-King-Platz 6, D-20146 Hamburg, Germany.
Sund
C
C
Thiem
J
J
Giesler
A
A
Kopf
J
J
D002241:Carbohydrates / Q000737:chemistry*; D018360:Crystallography, X-Ray; D003500:Cyclization; D004988:Ethers, Cyclic / Q000138:chemical synthesis / Q000737:chemistry; D005690:Galactose / Q000031:analogs & derivatives* / Q000737:chemistry*; D007094:Imides / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008358:Mannose / Q000031:analogs & derivatives* / Q000737:chemistry*; D015394:Molecular Structure; D010777:Photochemistry; D014466:Ultraviolet Rays
D002241:Carbohydrates; D004988:Ethers, Cyclic; D007094:Imides; D008358:Mannose; D005690:Galactose