The Effects of Conformational Constraints and Steric Bulk in the Amino Acid Moiety of Philanthotoxins on AMPAR Antagonism
作者:Malene R. Jørgensen、Christian A. Olsen、Ian R. Mellor、Peter N. R. Usherwood、Matthias Witt、Henrik Franzyk、Jerzy W. Jaroszewski
DOI:10.1021/jm049906w
日期:2005.1.1
at ionotropic receptors (e.g., AChR or iGluR). To determine possible effects of variations of the amino acid side chain, a library consisting of seventeen PhTX-343 analogues was prepared. Thus, tyrosine was replaced by either apolar, conformationally constrained, or bulky amino acids, whereas the acyl unit and the polyamine moiety were kept unchanged. Analogues with tertiary amide groups were prepared
Philanthotoxin-343(PhTX-343)是黄蜂毒素PhTX-433的合成类似物,是离子型受体(例如AChR或iGluR)的非竞争性拮抗剂。为了确定氨基酸侧链变异的可能影响,制备了由17种PhTX-343类似物组成的文库。因此,酪氨酸被非极性,构象受限或庞大的氨基酸取代,而酰基单元和多胺部分保持不变。首次制备了具有叔酰胺基团的类似物。将五氟苯基酯用于酰胺键的形成,建立了费洛托辛溶液和固相合成的通用方案(总收率分别为39-90%和42-54%)。测试了这些类似物拮抗海藻酸盐诱导的爪蟾卵母细胞表达的大鼠脑mRNA的2-氨基-3-(3-羟基-5-甲基-4-异恶唑酰基)丙酸受体(AMPAR)的海因酸盐诱导电流的能力。这表明氨基酸部分中的空间体积被很好地耐受,并且表明与AMPAR的结合不涉及作为氢键供体的α-NHCO基团。