Disclosed herein is a class of linkable tetrasaccharide compounds that includes the amino phenyl glycoside of sialyl Lewis X (SLe.sup.X) and related analogs. These compounds have conjugatable nucleophilic groups, making them useful in preparing multimeric SLe.sup.X compositions. In particular, the disclosed SLe.sup.X compounds can be used to prepare selectin binding ligand conjugates by linking them to a reporter moiety, such as a contrast agent, a radiodiagnostic agent, or a cytotoxic or chemotherapeutic agent. The SLe.sup.X compounds and conjugates of the invention exhibit binding to selectin that is similar to native Sialyl Le.sup.x, and are, therefore, useful for diagnosing and treating selectin-mediated disorders and related conditions.