Kamal, Ahmed; Ramesh; Srinivas; Ramulu; Laxman; Rehana, Tasneem; Deepak; Achary; Nagarajaram Bioorganic and Medicinal Chemistry, 2004, vol. 12, # 20 p. 5427 - 5436 doi: 10.1016/j.bmc.2004.07.045