262847-01-8Relevant articles and documents
Asymmetric synthesis of (-)-eburnamonine and (+)-epi-eburnamonine from (4s)-4-ethyl-4-[2-(hydroxycarbonyl)ethyl]-2-butyrolactone
Wee,Yu
, p. 8935 - 8943 (2007/10/03)
The key chiral nonracemic 4,4-disubstituted 2-butyrolactone carboxylic acid, (S)-4, is readily accessible via an efficient and stereospecific dirhodium(II) tetraacetate catalyzed tertiary C-H insertion reaction of the diazomalonate (S)-5. The coupling of the acid (S)-4 with tryptamine produces the amide (S)-3, which is then transformed into the aldehyde 23 and hydroxy-lactam 24. Acid-mediated Pictet-Spengler cyclization of 23 and 24 produces the tetracyclic indole lactams (1S,-12bS)-25a and (1S,12bR)-25b. Compounds 25a and 25b are converted, via the lactam alcohols 30a and 30b, to (-)-eburnamonine (1a) and (+)-epi-eburnamonine (1b).
Total synthesis of (-)-eburnamonine and (+)-epi-eburnamonine from a chiral non-racemic 4,4-disubstituted γ-lactone
Wee, Andrew G.H.,Yu, Qing
, p. 587 - 590 (2007/10/03)
The total synthesis of (-)-eburnamonine and (+)-epi-eburnamonine was successfully achieved using a key chiral non-racemic 4,4-disubstituted γ- lactone 4 that was prepared via the Rh(II) carbenoid mediated tertiary C-H insertion reaction of a chiral non-racemic diazomalonate 5. (C) 2000 Elsevier Science Ltd.