These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Synthesis of Aminocyclitols by Intramolecular Reductive Coupling of Carbohydrate Derived delta- and epsilon-Functionalized Oxime Ethers Promoted by Tributyltin Hydride or Samarium Diiodide.
    Author: Marco-Contelles J, Gallego P, Rodríguez-Fernández M, Khiar N, Destabel C, Bernabé M, Martínez-Grau A, Chiara JL.
    Journal: J Org Chem; 1997 Oct 17; 62(21):7397-7412. PubMed ID: 11671857.
    Abstract:
    The intramolecular reductive coupling of a series of simple or polyoxygenated oxime ethers delta- or epsilon-functionalized with bromide, alpha,beta-unsaturated ester, aldehyde, or ketone groups is reported. The cyclization of a nitrile-tethered aldehyde is also studied. These reductive couplings are promoted by tributyltin hydride or samarium diiodide. The reactions proceed under mild conditions, in good chemical yield, and with high stereoselectivity. When applied to highly functionalized substrates derived from carbohydrates, this approach provides a selective entry to enantiomerically pure aminocyclitols of varying regio- and stereochemistry. In particular, the reductive coupling reaction of carbonyl-tethered oxime ethers promoted by samarium diiodide can be performed in a one-pot sequence, following a Swern oxidation step, allowing the direct transformation of hydroxyl-tethered oxime ethers into the corresponding aminocyclitols. Moreover, the resultant O-benzylhydroxylamine products of these cyclizations can be further reduced in situ with excess samarium diiodide, in the presence of water, to the corresponding amino alcohols in excellent yields. Some transformations of these compounds are discussed.
    [Abstract] [Full Text] [Related] [New Search]