87400-38-2Relevant academic research and scientific papers
Iodide/H2O2 catalyzed intramolecular oxidative amination for the synthesis of 3,20-pyrrolidinyl spirooxindoles
Gao, Yu-Ting,Jin, Xiao-Yang,Liu, Qi,Liu, An-Di,Cheng, Liang,Wang, Dong,Liu, Li
, (2018/09/12)
An ammonium iodide/hydrogen peroxide-mediated intramolecular oxidative amination of 3-aminoalkyl-2-oxindoles was achieved, affording the corresponding 3,20-pyrrolidinyl spirooxindoles and their 6- or 7-membered analogous in moderate to high yields. This metal-free procedure features very mild reaction conditions, non-toxicity and easily handled hydrogen peroxide as a clean oxidant.
Syntheses of strychnine, norfluorocurarine, dehydrodesacetylretuline, and valparicine enabled by intramolecular cycloadditions of Zincke aldehydes
Martin, David B. C.,Nguyen, Lucas Q.,Vanderwal, Christopher D.
experimental part, p. 17 - 46 (2012/02/04)
A full account of the development of the base-mediated intramolecular Diels-Alder cycloadditions of tryptamine-derived Zincke aldehydes is described. This important complexity-generating transformation provides the tetracyclic core of many indole monoterpene alkaloids in only three steps from commercially available starting materials and played a key role in short syntheses of norfluorocurarine (five steps), dehydrodesacetylretuline (six steps), valparicine (seven steps), and strychnine (six steps). Reasonable mechanistic possibilities for this reaction, a surprisingly facile dimerization of the products, and an unexpected cycloreversion to regenerate Zincke aldehydes under specific conditions are also discussed.
Syntheses of 5a′-homo-vinblastine and congeners designed to establish structural determinants for isolation of atropisomers
Kuehne,Cowen,Xu,Borman
, p. 5303 - 5316 (2007/10/03)
The syntheses of 5a′-homo-vinblastine (3a) and its C-20′ methyl congener 62a were achieved. In contrast to vinblastine, these compounds did not allow isolation of atropisomers because of their lower conformational inversion barrier. However, annelation of a six-membered ring to the conformationally mobile D′-piperidine ring provided an isolated atropisomer 81a, which could be converted to its lower energy conformation 65a on heating. The 5a′-homo-vinblastine congeners 3a, 62a, and 65a showed vinblastine-like inhibition of tubulin polymerization and cytotoxicity to L1210 leukemia cells, albeit at lower potency for the latter activity, than that found with the corresponding compounds in the vinblastine series.
