Substituted urea compounds useful in the treatment of diseases and C.sub.1-3alkyleneOR.sup.3 conditions related to DNA damage or lesions in DNA replication are disclosed formula (I), wherein X.sup.1 is null, --O--, --S--, --CH.sub.2--, or --N(R.sup.1)--; X.sup.2 is --O--, . -.English Pound.>. -, or --N(R.sup.1)--,--. . Y xs 0 or S; or =y represents two hydrogen atoms attached to a common carbon atom, --W is selected from the group consisting of heteroaryl, aryl, heterocycloalkyl, cycloalkyl, and .sub.C1-6alkyl substituted with a heteroaryl. or aryl group; R.sup.6 is --C.ident.C--R.sup.7 or heteroaryl; R.sup.8, R.sup.9, and R.sup.10, independently, are selected from the group consisting of halo, optionally substituted C.sub.1-6alkyl, C.sub.2-6alkenyl, C.sub.2-6alkynyl, OCP.sub.3, CF.sub.3, NO.sub.2, CN, NC, N(R.sup.3).sub.2, OR.sup.3, CO.sub.2R.sup.3, C(O)N (R.sup.3).sub.2, C(O)R.sup.3, N(R.sup.1)COR.sup.3, N(R.sup.1)C(O)OR.sup.3, N(R.sup.8)C(O)OR.sup.3, N(R.sup.1)C(O)C.sub.1-3alkyleneC(O)R.sup.3, N(R.sup.1)C(O)C.sub.1 -3alkyleneC(O)OR.sup.3, N(R.sup.1)C(O)C.sub.1-3alkyleneOR.sup.3, N(R.sup.1)C(O)C.sub.1-3alkyleneNHC(O)OR.sup.3, N(R.sup.1)C(O)C.sub.1-3alkyleneSO.sub.2.NR.sup.3, C.sub.1-3alkyleneOR.sup.3, and SR.sup.3; Methods of making the compounds, and their use as therapeutic agents, for example, in treating cancer and other diseases characterized by defects in DNA replication, chromosome segregation, or cell division also are disclosed. ##STR00001##