Reactions of indole derivatives with oxiranes and aziridines on silica. Synthesis of beta-carbolin-1-one mimic of pancratistatin.
[reaction: see text] Indole and several indoles functionalized at C-2 were condensed with oxiranes, vinyloxiranes, aziridines, and vinylaziridines in the solid state on the surface of silica. The yields of these reactions were compared to those obtained from Lewis acid-catalyzed ring-opening reactions performed in solution and found to be superior in each case. The solid-phase aziridine opening constituted a key step in the synthesis of the beta-carbolin-1-one mimic of pancratistatin. Methyl 2-indolecarboxylate was found to react on the silica gel surface with N-tosylvinylaziridine in 68% yield. A nine-step synthesis of the pancratistatin mimic has been attained. The additional key transformation in this synthesis involved silica gel-catalyzed opening of an epoxide and hydrolysis of an acetonide. Detailed experimental procedures and full characterization are reported for all new compounds.
Hudlicky
Tomas
T
Department of Chemistry, Brock University, St. Catharines, Ontario, Canada L2S 3A1. thudlicky@brocku.ca
Rinner
Uwe
U
Finn
Kevin J
KJ
Ghiviriga
Ion
I
D047151:Amaryllidaceae Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry*; D001388:Aziridines / Q000737:chemistry*; D002243:Carbolines / Q000138:chemical synthesis*; D020650:Combinatorial Chemistry Techniques; D005027:Ethylene Oxide / Q000031:analogs & derivatives / Q000737:chemistry; D007211:Indoles / Q000737:chemistry*; D007546:Isoquinolines / Q000138:chemical synthesis* / Q000737:chemistry*; D018716:Molecular Mimicry; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010946:Plants, Medicinal / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry
D047151:Amaryllidaceae Alkaloids; D001388:Aziridines; D002243:Carbolines; D007211:Indoles; D007546:Isoquinolines; C033132:aziridine; D012822:Silicon Dioxide; C044997:pancratistatin; D005027:Ethylene Oxide