Samarium(II) iodide-promoted hydroxyalkylations of indole 3-carbonyls. An expedient approach to pyrrolidino[1,2-a]indoles and furo[3,4-b]indoles
作者:Jiann-Shyng Shiue、Jim-Min Fang
DOI:10.1039/c39930001277
日期:——
3-Formyl-, 3-acetyl-1-methylindole and their 2-cyano analogues undergo intra- and inter-molecular hydroxyalkylations on treatment with samarium(II) iodide in the presence of a cosolvent hexamethylphosphoramide; the intramolecular coupling products have the structure prototype of mytomycins and the intermolecular coupling products are readily converted to furoindoles as synthetic equivalents of indole-2,3-quinodimethanes.
By the assistance of an N-sulfonyl group or a cyano group at the C-2 position, hydroxyalkylations of indole-3-carbonyls were achieved by the promotion of samarium diiodide. The indolecarbonyl coupling reactions proceeded in high stereoselectivity via chelate transition states. Intramolecular indolecarbonyl couplings of 1-(3-oxopropyl)indole-3-carboxaldehydes were realized as the indole-carbonyl group was more reactive toward SmI2 than the aliphatic carbonyl group. Elaboration of the coupling products with oxidizing agents, acid, phosphorus pentasulfide (or Lawesson's reagent), amines, and hydrazine led to a variety of indole derivatives and indole-fused polycyclic compounds of synthetic interest and pharmaceutical uses.
Synthesis, mechanism of action, and biological evaluation of mitosenes
作者:E. O. M. Orlemans、W. Verboom、M. W. Scheltinga、D. N. Reinhoudt、P. Lelieveld、H. H. Fiebig、B. R. Winterhalter、J. A. Double、M. C. Bibby
DOI:10.1021/jm00127a035
日期:1989.7
Mitosenes of both the pyrrolo- and pyrido[1,2-a]indole type have been prepared via modification of these heterotricyclic compounds. Several mitosenes have been studied for their reactions with nucleophiles under reductive conditions. The results of these experiments show that the biologicalactivity of mitosenes is based on the mechanism of bioreductive activation. When both leaving groups at C-1 and