Total synthesis of ent-dihydrocorynantheol by using a proline-catalyzed asymmetric addition reaction.
[reaction: see text] 9-Tosyl-3,4-dihydro-beta-carboline reacted with 3-ethyl-3-buten-2-one in the presence of (S)-proline to give (3R,12bR)-3-ethyl-12-tosyl-3,4,6,7,8,9,10,11,12,12b-decahydro-1H-indolo[2,3-a]quinolizin-2-one in complete enantio- and diastereoselectivity. The compound thus obtained was readily transformed to ent-dihydrocorynantheol in three steps.
Itoh
Takashi
T
School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan. itoh-t@pharm.showa-u.ac.jp
Yokoya
Masashi
M
Miyauchi
Keiko
K
Nagata
Kazuhiro
K
Ohsawa
Akio
A
D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D015394:Molecular Structure; D011392:Proline / Q000737:chemistry*; D013237:Stereoisomerism
D000470:Alkaloids; C007398:dihydrocorynantheol; D011392:Proline