Contains The Structure (n)-p-(x-*acyl), (n)-p-(x-*z) Or (n)-p-(x-*cyano) Where Z Is An Atom Other Than C Or H, X Is A Chalcogen Atom, And * Indicates A Direct Bond To The Adjacent X Atom (9/24a9; 9/24a9+m; 9/24a9+q; 9/24a9+u; 9/24a9+w) Patents (Class 987/192)