The present invention is a compound having a structure represented by the following formula (1): ##STR00001## and an antibody to BSH obtained by using the compound as a hapten and using a complex of the hapten and a high-molecular compound as an antigen. By using the present invention, it becomes possible to provide a hapten compound for preparing an antibody recognizing BSH highly sensitively and highly selectively, an antibody to BSH, as well as a kit for measuring BSH and an immunological measuring method having high sensitivity and excellent in quantitative property using the antibody.