Artificially synthesized antigen of sildenafil and derivatives thereof as well as preparation method and application of antigen

The invention belongs to the field of pharmaceutical chemistry, and discloses an artificially synthesized antigen of sildenafil and derivatives thereof as well as a preparation method and an application of the antigen. The artificially synthesized antigen of the sildenafil and the derivatives of the sildenafil is the chemical compound with the structure as shown in the formula (I) or the formula (I'). The sildenafil compounds and particularly the artificially synthesized antigen (as shown in the formula (I) or the formula (I')) of the sildenafil are firstly synthesized, and the synthesized artificially synthesized antigen is good in immunogenicity and reactivity and can be used for preparing a corresponding monoclonal antibody, so that the colloidal gold test paper for detecting the sildenafil compounds and particularly the sildenafil can be further produced, and the colloidal gold test paper can be used for detecting whether a sample has the sildenafil or the structural analogue of the sildenafil at any time