Ornelas, Martha A.; Gonzalez, Javier; Sach, Neal W.; Richardson, Paul F.; Bunker, Kevin D.; Linton, Angelica; Kephart, Susan E.; Pairish, Mason; Guo, Chuangxing Tetrahedron Letters, 2011, vol. 52, # 37 p. 4760 - 4763 doi: 10.1016/j.tetlet.2011.07.021