468-22-4Relevant articles and documents
Asymmetric synthesis method for crinum asiaticum alkaloid
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Paragraph 0110; 0113-0114, (2019/01/23)
The invention relates to an asymmetric synthesis method for crinum asiaticum alkaloid taking the asymmetric catalytic hydrogenation reaction as the key step. According to the method, through racemic asymmetric catalytic hydrogenation kinetic resolution for replacing cyclohexanone, quick asymmetric synthesis for 22 kinds of crinum asiaticum alkaloid comprising (-)-crinine, (+)-epivittatine, (+)-vittatine, (-)-epicrinine and the like and eight analogues is achieved concisely and efficiently.
Efficient syntheses of (-)-crinine and (-)-aspidospermidine, and the formal synthesis of (-)-minfiensine by enantioselective intramolecular dearomative cyclization
Du, Kang,Yang, He,Guo, Pan,Feng, Liang,Xu, Guangqing,Zhou, Qinghai,Chung, Lung Wa,Tang, Wenjun
, p. 6247 - 6256 (2017/08/29)
Polycyclic alkaloids bearing all-carbon quaternary centers possess a diversity of biological activities and are challenging targets in natural product synthesis. The development of a general and asymmetric catalytic method applicable to the efficient syntheses of a series of complex polycyclic alkaloids remains highly desirable in synthetic chemistry. Herein we describe an efficient palladium-catalyzed enantioselective dearomative cyclization which is capable of synthesizing two important classes of tricyclic nitrogen-containing skeleton, chiral dihydrophenanthridinone and dihydrocarbazolone derivatives bearing all-carbon quaternary centers, in excellent yields and enantioselectivities. The P-chiral monophosphorus ligand AntPhos is crucial for the reactivity and enantioselectivity, and the choice of the N-phosphoramide protecting group is essential for the desired chemoselectivity. This method has enabled the enantioselective total syntheses of three distinctive and challenging biologically important polycyclic alkaloids, specifically a concise and gram-scale synthesis of (-)-crinine, an efficient synthesis of indole alkaloid (-)-aspidospermidine and a formal enantioselective synthesis of (-)-minfiensine.
TOTAL SYNTHESES OF (+/-)-CRININE AND (+/-)-BUPHANISINE
Martin, Stephen F.,Campbell, Carlton L.
, p. 503 - 506 (2007/10/02)
The concise total syntheses of the Amaryllidaceae alkaloids (+/-)-crinine (1) and (+/-)-buphanisine (2) have been completed by a strategy that features the application of a general procedure for the elaboration of a quaternary carbon at a carbonyl center
