analgesics nicomorphine (Vilan), and dipropanoylmorphine; there is also the latter's dihydromorphine analogue, diacetyldihydromorphine (Paralaudin). Two other 3,6 diesters of morphine invented in 1874–75 along with diamorphine, dibenzoylmorphine and acetylpropionylmorphine, were made as substitutes after it was outlawed in 1925 and, therefore, sold as the first "designer drugs" until they were outlawed