219583-98-9Relevant academic research and scientific papers
Enantiospecific Total Synthesis of the Sarpagine Related Indole Alkaloids Talpinine and Talcarpine as Well as the Improved Total Synthesis of Alstonerine and Anhydromacrosalhine-methine via the Asymmetric Pictet-Spengler Reaction
Yu, Peng,Wang, Tao,Li, Jin,Cook, James M.
, p. 3173 - 3191 (2007/10/03)
The enantiospecific total synthesis of talpinine 1 and talcarpine 2 has been accomplished from D-(+)-tryptophan in 13 steps (11 reaction vessels) in 10% and 9.5% overall yields, respectively. Moreover, this synthetic approach has been employed for the improved synthesis of alstonerine 3 and anhydromacrosalhine-methine 4 in 12% and 14% overall yield, respectively. A convenient synthetic route for the enantiospecific, stereospecific preparation of the key intermediate (-)-Na-H, Nb-benzyl tetracyclic ketone 15a via the asymmetric Pictet-Spengler reaction on a multihundredgram scale has been developed. A diastereocontrolled (>30:1) anionic oxy-Cope rearrangement and the intramolecular rearrangement to form ring-E and an Nb-benzyl/Nb-methyl transfer reaction also served as key steps. This general approach can now be utilized for the synthesis of macroline/ sarpagine related indole alkaloids and their antipodes for biological screening.
General approach for the synthesis of ajmaline/sarpagine indole alkaloids: Enantiospecific total synthesis of (+)-ajmaline, alkaloid G, and norsuaveoline via the asymmetric Pictet-Spengler reaction
Li, Jin,Wang, Tao,Yu, Peng,Peterson,Weber,Soerens,Grubisha,Bennett,Cook
, p. 6998 - 7010 (2007/10/03)
A general approach (oxyanion-Cope strategy) for the synthesis of sarpagine/ajmaline indole alkaloids has been developed. (+)-Ajmaline 1 and alkaloid G 2 as well as norsuaveoline 3 have been synthesized from D-(+)-tryptophan in enantiospecific fashion via
