... Please enable JavaScript to use all the features on this page. Tetrahedron Letters. Volume 33, Issue 23, 2 June 1992, Pages 3293–3296. Cover image Cover image. ... References. 1; a) WM Kazmierski, VJ Hruby; Tetrahedron Lett., 32 (1991), p. 5769 and references cited therein. ...