nBu4NI-catalyzed cross-coupling of benzyl and allylic compounds with N-hydroxyphthalimide for the synthesis of alkyloxyamines were realized for the first time.
O-alkylhydroxylamines as rationally-designed mechanism-based inhibitors of indoleamine 2,3-dioxygenase-1
作者:William P. Malachowski、Maria Winters、James B. DuHadaway、Ariel Lewis-Ballester、Shorouk Badir、Jenny Wai、Maisha Rahman、Eesha Sheikh、Judith M. LaLonde、Syun-Ru Yeh、George C. Prendergast、Alexander J. Muller
DOI:10.1016/j.ejmech.2015.12.028
日期:2016.1
Indoleamine 2,3-dioxygenase-1 (IDO1) is a promising therapeutic target for the treatment of cancer, chronic viral infections, and other diseases characterized by pathological immune suppression. Recently important advances have been made in understanding IDO1's catalytic mechanism. Although much remains to be discovered, there is strong evidence that the mechanism proceeds through a heme-iron bound alkylperoxy transition or intermediate state. Accordingly, we explored stable structural mimics of the alkylperoxy species and provide evidence that such structures do mimic the alkylperoxy transition or intermediate state. We discovered that O-benzylhydroxylamine, a commercially available compound, is a. potent sub-micromolar inhibitor of IDO1. Structure activity studies of over forty derivatives of O-benzylhydroxylamine led to further improvement in inhibitor potency, particularly with the addition of halogen atoms to the meta position of the aromatic ring. The most potent derivatives and the lead, O-benzylhydroxylamine, have high ligand efficiency values, which are considered an important criterion for successful drug development. Notably, two of the most potent compounds demonstrated nanomolar-level cell-based potency and limited toxicity. The combination of the simplicity of the structures of these compounds and their excellent cellular activity makes them quite attractive for biological exploration of IDO1 function and antitumor therapeutic applications. (C) 2015 Elsevier Masson SAS. All rights reserved.
This letter reports a new labeling method of fucoidan and more precisely of its monomer, L-fucose. We studied the coupling processes of new aryliodide precursors to L-fucose in order to prepare the next step, that is, the fucoidan radiolabeling. The use of precursors containing hydrazide and hydroxylamines is an alternative procedure avoiding the use of toxic borohydride or organic borane used for reductive amination. These coupling reactions are efficient and stereoselective. They provide stable products. (c) 2006 Elsevier Ltd. All rights reserved.