Structure and Total Synthesis of HF-7, a Neuroactive Glyconucleoside Disulfate from the Funnel-Web Spider <i>Hololena curta</i>
作者:Jinping McCormick、Yingbo Li、Kevin McCormick、Howard I. Duynstee、Anke K. van Engen、Gijs A. van der Marel、Bruce Ganem、Jacques H. van Boom、Jerrold Meinwald
DOI:10.1021/ja990274q
日期:1999.6.1
Spider venom toxins have attracted considerable attention for their ability to block the action of excitatory amino acids such as glutamate and aspartate. A new neuroactive compound designated HF-7 was isolated in 1993 from the venom of a funnel-web spider, Hololena curta. HF-7 was shown to block kainate receptors and, albeit weakly, L-type calcium channels. Spectroscopic analysis established the structure of HF-7 as an unusual acetylated, disulfated fucopyranosyl guanosine, with the acetate ester attached at the 4-position of an alpha-linked fucose ring and two sulfates attached to the ribose ring. Because insufficient quantities of natural HF-7 were available for chemical degradation or X-ray diffraction analysis, total synthesis of three candidate structures was used to establish the identity of HF-7. Once HF-7 was fully characterized as 3'-O-(4 "-O-acetyl-alpha-L-fucopyranosyl)gnanosine-2',5-dusulfate, an improved, targeted synthesis of the natural product was developed.