2883-99-0Relevant articles and documents
Construction of Chiral Tetrahydro-β-Carbolines: Asymmetric Pictet–Spengler Reaction of Indolyl Dihydropyridines
Wang, Shou-Guo,Xia, Zi-Lei,Xu, Ren-Qi,Liu, Xi-Jia,Zheng, Chao,You, Shu-Li
supporting information, p. 7440 - 7443 (2017/06/13)
A highly efficient synthesis of the enantioenriched tetrahydro-β-carbolines was developed by using a chiral phosphoric acid catalyzed Pictet–Spengler reaction of indolyl dihydropyridines. The reaction proceeds under mild reaction conditions to afford the desired chiral tetrahydro-β-carbolines in good to excellent yields (up to 96 %) and high enantioselectivities (up to 99 % ee). With this method, a formal synthesis of tangutorine and a total synthesis of deplancheine were achieved in a highly efficient manner.
GENERAL METHODS OF SYNTHESIS OF INDOLE ALKALOIDS - 14. SHORT ROUTES OF CONSTRUCTION OF YOHIMBOID AND AJMALICINOID ALKALOID SYSTEMS AND THEIR 13C NUCLEAR MAGNETIC RESONANCE SPECTRAL ANALYSIS.
Wenkert,Chang,Chawla,Cochran,Hagaman,King,orito
, p. 3645 - 3661 (2007/10/04)
Conceptually new schemes of synthesis of indole alkaloids are introduced. The yohimboid ring system is constructed by the sequential treatment of 1-tryptophyl-3-( beta -ketobutyl)pyridinium bromide with base and acid. Hydrogenation of the product yields d,l-pseudoyohimbone. The ajmalicinoid ring system is formed by the exposure of 1-tryptophyl-3-acetylpyridinium bromide to sodio dimethyl malonate and then to acid, followed by hydrogenation. Subsequent reduction and dehydration of the products lead to the racemates of the alkaloids tetrahydroalstonine and akuammigine as well as isomers of ajmalicine. Shifts of specific carbons are found to be of stereochemically diagnostic value.