Evans, D. A.; Mitch, C. H.
Tetrahedron Letters, 1982 , vol. 23, # 3 p. 285 - 288

Burke, Terrence R.; Jacobson, Arthur E.; Rice, Kenner C.; Weissman, Ben Avi; Huang, Hsueh-Cheng; Silverton, J. V.
Journal of Medicinal Chemistry, 1986 , vol. 29, # 5 p. 748 - 751

Evans, D. A.; Mitch, C. H.
Tetrahedron Letters, 1982 , vol. 23, # 3 p. 285 - 288