Butcher, John W.; Liverton, Nigel J.; Selnick, Harold G.; Elliot, Jason M.; Smith, Garry R.; Tebben, Andrew J.; Pribush, David A.; Wai, John S.; Claremon, David A.
Tetrahedron Letters, 1996 , vol. 37, # 37 p. 6685 - 6688