201350-53-0Relevant academic research and scientific papers
Concise Total Synthesis of (?)-Affinisine Oxindole, (+)-Isoalstonisine, (+)-Alstofoline, (?)-Macrogentine, (+)-Na-Demethylalstonisine, (?)-Alstonoxine A, and (+)-Alstonisine
Stephen, Michael Rajesh,Rahman, M. Toufiqur,Tiruveedhula, V. V. N. Phani Babu,Fonseca, German O.,Deschamps, Jeffrey R.,Cook, James M.
, p. 15805 - 15819 (2017/10/23)
A highly enantio- and diastereoselective strategy to access any member of the sarpagine/macroline family of oxindole alkaloids via internal asymmetric induction was developed from readily available d-(+)-tryptophan. At the center of this approach was the diastereospecific generation of the spiro[pyrrolidine-3,3′-oxindole] moiety at an early stage via a tert-butyl hypochlorite-promoted oxidative rearrangement of a chiral tetrahydro-β-carboline derivative. This key branching point determined the spatial configuration at the C-7 spiro center to be entirely 7R or 7S. Other key stereospecific processes were the asymmetric Pictet–Spengler reaction and Dieckmann cyclization, which were scalable to the 600 and 150 gram levels, respectively. Execution of this approach resulted in first enantiospecific total synthesis of (+)-isoalstonisine and (?)-macrogentine from the chitosenine series (7R), as well as (+)-alstonisine, (+)-alstofoline, (?)-alstonoxine A and (+)-Na-demethylalstonisine from the alstonisine series (7S).
Diastereospecific synthesis of ketooxindoles. Potential intermediates for the synthesis of alstonisine as well as for voachalotine related oxindole alkaloids
Yu, Peng,Cook, James M.
, p. 8799 - 8802 (2007/10/03)
A convenient method has been developed to convert N(a)-H tetracyclicketone la into the two corresponding oxindolesr[(7)] diastereospecifically. Treatment of the N(a)-H, N(b)-benzyl tetracyclicketone 1a with t-BuOCl provided diastereomer 2a (related to Voacanga oxindoles), whereas the same process with Nb-H (1b) or N(b)-benzoyl (1c) substituted analogs funished the diastereomers 2b and 2c (related to alstonisine), respectively.
