Definition: Two-ring crystalline hydrocarbons isolated from coal tar. They are used as intermediates in chemical synthesis, as insect repellents, fungicides, lubricants, preservatives, and, formerly, as topical antiseptics.
6-(bromomethylene)tetrahydro-3-(1-naphthaleneyl)-2H-pyran-2-one [ 6-(bromomethylene)tetrahydro-3-(1-naphthalenyl)-2H-pyran-2-one,6-BTNPO,BEL cpd,HELSS,bromoenol lactone ] structure given in first source; potent irreversible, mechanism-based inhibitor of myocardial calcium-independent phospholipase A2