1668-85-5Relevant articles and documents
Total synthesis of (±)-galanthamine from GABA through regioselective aryne insertion
Venkatesh, Telugu,Mainkar, Prathama S.,Chandrasekhar, Srivari
, p. 2192 - 2198 (2019)
The total synthesis of (±)-galanthamine is achieved in ~5% overall yield using a key regioselective aryne insertion reaction into a GABA (γ-amino butyric acid) derivative. The strategy presented involves only two sub-critical temperature reactions and less than five chromatographic purifications to achieve the synthesis of galanthamine.
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Bhandarkar,J.G.,Kirby,G.W.
, p. 1224 - 1227 (1970)
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Studies on the synthesis of heterocyclic compounds. CCCXV. Modified total synthesis of (plus or minus)-galanthamine through phenol oxidation.
Kametani,Yamaki,Yagi,Fukumoto
, p. 2602 - 2605 (1969)
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The application of a specific morphinan template to the synthesis of galanthamine
Yamamoto, Naoshi,Okada, Takahiro,Harada, Yukimasa,Kutsumura, Noriki,Imaide, Satomi,Saitoh, Tsuyoshi,Fujii, Hideaki,Nagase, Hiroshi
, p. 5751 - 5758 (2017/09/05)
(–)-Galanthamine (4) was synthesized from naltrexone (1) in 18 steps with 3% total yield by overcoming many specific side reactions derived from the 4,5-epoxymorphinan skeleton. The key features are cleavage of the D-ring by the Hofmann elimination and the following the one-pot C9–C10 and C9–14 bond cleavages concomitant with the C9 removal by the OsO4–NaIO4 combination reaction. Then, the treatment with zinc powder in acetic acid led to not only removal of the 2,2,2-trichloroethoxycarbonyl (Troc) group, but also reductive amination of the resulting imine to give the desired 7-membered ring.
Stereoselective syntheses of galanthamine and its stereoisomers by complementary Luche and L-selectride reductions
Trinadhachari, Ganala Naga,Kamat, Anand Gopalkrishna,Raghu Babu, Korupolu,Sanasi, Paul Douglas,Prabahar, Koilpillai Joseph
, p. 117 - 124 (2014/02/14)
A diastereodivergent approach for the stereoselective syntheses of all four stereoisomers of galanthamine, (-)-galanthamine 1, (+)-galanthamine 2, (-)-epigalanthamine 3, and (+)-epigalanthamine 4, from (±)-narwedine 5 is reported. Thus (±)-narwedine 5 was resolved by dynamic kinetic resolution to obtain enantiomerically pure (-)-narwedine 6 and (+)-narwedine 7. Each enantiomerically pure isomer of narwedine was subjected to Luche and L-selectride reactions to obtain all four isomers of galanthamine. In these reactions, the (-)-galanthamine 1 and (+)-galanthamine 2 isomers were obtained with an enantiomeric purity of >99.5%, whereas (-)-epigalanthamine 3 and (+)-epigalanthamine 4 are obtained with a chiral purity of >97%. The axial hydride attack by the Luche reduction and the equatorial hydride attack by the L-selectride reduction on the cyclic enone system are explored in the stereoselective synthesis of the galanthamine isomers and thus it was demonstrated that the stereoselective synthesis involving the Luche and L-selectride reductions are complementary in yielding enantiomeric stereogenic centers from a prochiral carbonyl group on the cyclic enone system.