... of 4,4-Disubstituted-3-oxo-1,2,5-thiadiazolidine 1,1 -Dioxides Zejun Xiao and Jack W. Timberlake* Department of Chemistry, University of ... J. Heterocyclic Chem., 37, 773 (2000). ... m, 2H, CH2), 3.46 (m, 2H, CH2), 5.47 (s, IH, NH), 7.15-7.31 (m, 6H, Ph), 7.50 ppm (d, 2H, J = 7.2 Hz ...