Author(s)

C. Zanato, S. Watson, G. S. Bewick, W. T. Harrison, M. Zanda

ISBN

1477-0539 (Electronic) 1477-0520 (Linking)

Publication year

2014

Periodical

Org Biomol Chem

Periodical Number

47

Volume

12

Pages

9638-43

Author Address

Kosterlitz Centre for Therapeutics, Institute of Medical Sciences, University of Aberdeen, Foresterhill, AB25 2ZD, Scotland, UK. m.zanda@abdn.ac.uk.

Full version

(-)-Kainic acid potently increases stretch-induced afferent firing in muscle spindles, probably acting through a hitherto uncloned phospholipase D (PLD)-coupled mGlu receptor. Structural modification of (-)-kainic acid was undertaken to explore the C-4 substituent effect on the pharmacology related to muscle spindle firing. Three analogues 1a-c were synthesised by highly stereoselective additions of a CF3, a hydride and an alkynyl group to the Re face of the key pyrrolidin-4-one intermediate 5a followed by further structural modifications. Only the 4-(1,2,3-triazolyl)-kainate derivative 1c retained the kainate-like agonism, increasing firing in a dose-dependent manner. Further modification of 1c by introduction of a PEG-biotin chain on the 1,2,3-triazole fragment afforded compound 14 which retained robust agonism at 1 muM and appears to be suitable for future use in pull-down assays and far western blotting for PLD-mGluR isolation.