The Effects of Conformational Constraints in the Polyamine Moiety of Philanthotoxins on AMPAR Inhibition
作者:Henrik Franzyk、John W. Grzeskowiak、Denis B. Tikhonov、Jerzy W. Jaroszewski、Ian R. Mellor
DOI:10.1002/cmdc.201402109
日期:2014.7.8
Philanthotoxin‐433 (PhTX‐433) is a known potent inhibitor of ionotropic glutamate receptors, and analogues have been synthesised to identify more potent and selective antagonists. Herein we report the synthesis of four PhTXs with a cyclopropane moiety introduced into their polyamine chain, and their inhibition of an α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid (AMPA) receptor subtype by using
Solid-Phase Synthesis of Rigid Acylpolyamines Using Temporary <i>N</i>-4,4‘-Dimethoxytrityl Protection in the Presence of Trityl Linkers
作者:Christian A. Olsen、Matthias Witt、Jerzy W. Jaroszewski、Henrik Franzyk
DOI:10.1021/jo049278q
日期:2004.9.1
An N-protection protocol employing the 4,4'-dimethoxytrityl (Dmt) group in combination with borane reduction of resin-bound polyamides was shown to be an efficient methodology that enables synthesis of novel analogues of natural acylpolyamine toxins. Thus, three philanthotoxins containing polyamine chains with piperidyl and cyclohexyl structural elements, which introduce conformational rigidity, increased lipophilicity, and altered proteolytic properties, were obtained in 39-44% overall yield.
Fukuyama–Mitsunobu alkylation in amine synthesis on solid phase revisited: N-alkylation with secondary alcohols and synthesis of curtatoxins
作者:Christian A. Olsen、Matthias Witt、Steen H. Hansen、Jerzy W. Jaroszewski、Henrik Franzyk
DOI:10.1016/j.tet.2005.04.027
日期:2005.6
sulfonamides, as well as a method for synthesis of polyamines on solidphase. Here, an array of reagent combinations for solid-phase alkylation with secondary alcohols was examined in various solvents. The classical reagents DEAD–PPh3 as well as DEAD–PEt3 proved applicable for a single alkylation step. Sharply dropping yields in successive alkylation steps were identified as the most serious limitation of the
Diols as Building Blocks in Solid-Phase Synthesis of Polyamine Toxins by Fukuyama-Mitsunobu Alkylation
作者:Henrik Franzyk、Christian A. Olsen、Matthias Witt、Jerzy W. Jaroszewski
DOI:10.1055/s-2004-815426
日期:——
Philanthotoxin-433 (PhTX-433) is a polyamine wasp toxin that antagonizes certain ionotropic receptors. In the present work three analogues of PhTX-433 were synthesized in good overall yields (27-31%) employing a Fukuyama-Mitsunobu strategy on solid phase. Primary diols were used as building blocks in solid-phase synthesis of polyamines for the first time. Furthermore, experiments with sterically congested alcohols indicated that incorporation of such structures by the solid-phase Fukuyama-Mitsunobu approach is not possible.