3-{2-[4-(1,3-Dibutyl-4,6-dioxo-2-selenoxo-tetrahydro-pyrimidin-5-ylidene)-but-2-enylidene]-naphtho[1,2-d]thiazol-1-yl}-propane-1-sulfonic acid AIDS-165777 AIDS165777 Se-124(*Triethylammonium salt*)