Details

Autor(en) / Beteiligte

• Ito, Masayuki
• Clark, Cameron W
• Mortimore, Michael
• Goh, Jane Betty
• Martin, Stephen F

Titel

Biogenetically Inspired Approach to the Strychnos Alkaloids. Concise Syntheses of (±)-Akuammicine and (±)-Strychnine

Ist Teil von

• Journal of the American Chemical Society, 2001-08, Vol.123 (33), p.8003-8010

Ort / Verlag

United States: American Chemical Society

Erscheinungsjahr

2001

Quelle

MEDLINE

Beschreibungen/Notizen

• A linear synthesis of the indole alkaloid (±)-akuammicine (2) was completed by a novel sequence of reactions requiring only 10 steps from commercially available starting materials. The approach features a tandem vinylogous Mannich addition and an intramolecular hetero Diels−Alder reaction to rapidly assemble the pentacyclic heteroyohimboid derivative 8 from the readily available hydrocarboline 6. Oxidation of the E ring of 8 gave the lactone 9 that was converted into deformylgeissoschizine (11). The subsequent elaboration of 11 into 2 was effected by a biomimetically patterned transformation that involved sequential oxidation and base-induced skeletal reorganization. A variation of these tactics was then applied to the synthesis of the C(18) hydroxylated akuammicine derivative 36. Because 36 had previously been converted into strychnine (1) in four steps, its preparation constitutes a concise, formal synthesis of this complex alkaloid.