Lahm, George P.; Selby, Thomas P.; Freudenberger, John H.; Stevenson, Thomas M.; Myers, Brian J.; Seburyamo, Gilles; Smith, Ben K.; Flexner, Lindsey; Clark, Christopher E.; Cordova, Daniel Bioorganic and Medicinal Chemistry Letters, 2005, vol. 15, # 22 p. 4898 - 4906 doi: 10.1016/j.bmcl.2005.08.034