The complexes trans-RuCl2(BMSE)(2) (1), cis-RuCl2(BESE)(2) (2), trans-RuCl2(BPSE)(2) (3), and cis-RuCl2(BMSP)(2) (4) have been synthesized and characterized, including X-ray analyses [BMSE = 1,2-bis(methylsulfinyl)ethane, BESE = 1,2-bis(ethylsulfinyl)ethane, BPSE = 1,2-bis(propylsulfinyl)ethane, and BMSP = 1,3-bis(methylsulfinyl)propane]. Crystal data are as follows: 1 . H2O, triclinic, P1, a 8.863(1) Angstrom, b = 14.462(3) Angstrom, c 7.543(1) Angstrom, alpha = 103.39(1)degrees, beta = 113.31(1)degrees, gamma = 77.23(1)degrees, 2=2; 2 . MeOH, triclinic,

, n 14.858(2) Angstrom, b = 16.732(3) Angstrom, c 10.609(2) Angstrom, alpha 105.14(2)degrees, beta 93.34(2)degrees, gamma = 115.91(1)degrees, Z= 4; 3, orthorhombic, Aba2, a = 14.894(1) Angstrom, b = 7.501(1) Angstrom, c = 21.911(2) Angstrom, Z = 4; 4, orthorhombic, Pcab, a = 15.257(3) Angstrom, b = 18.138(2) Angstrom, c = 13.395(2) Angstrom, Z = 8. The structures were solved by the Patterson method and were refined by full-matrix least-squares procedures to R = 0.026, 0.026, 0.029, and 0.031 for 10461, 8952, 1594, and 5694 reflections with I > 3 sigma(I), for 1-4, respectively. Preliminary in vitro experiments with Chinese hamster ovary cells indicate that the trans-complexes accumulate in the cells and bind to DNA to a greater degree than the cis-complexes.