Synthesis of 1-deoxy-6-epicastanospermine and 1-deoxy-6,8a-diepicastanospermine.
Extension of the carbon spine of 2,3;4,5-di-O-isopropylidene-beta-D-fructopyranoside by oxidation at C-1 followed by a Wittig reaction using the phosphorane Ph3P = CHCO2Et gave an oct-4-ulose derivative, which was then transformed into the key intermediate 1-azido-1,2,3-trideoxy-D-arabino-oct-4-ulose. Catalytic hydrogenolysis of this azide, followed by reductive amination between the resulting 1-amino substituent and the 4-keto-group then gave a mixture of pyrrolidines. After sulphonylation at the terminal 8-position, the pyrrolidines were then cyclised further between the nitrogen and C-8 to give 1-deoxy-6-epicastanospermine and 1-deoxy-6,8a-diepicastanospermine.
Aamlid
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Department of Chemistry, King's College London, Great Britain.
Hough
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Richardson
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D000470:Alkaloids / Q000138:chemical synthesis*; D055598:Chemical Phenomena; D002621:Chemistry; D007212:Indolizines; D009682:Magnetic Resonance Spectroscopy; D008722:Methods; D015394:Molecular Structure
D000470:Alkaloids; D007212:Indolizines; C065905:1-deoxycastanospermine