What Is a Derivative?

Abstract

The concept of a ‘derivative’ is used widely in chemistry, where its precise meaning depends on the circumstances. However, numerous examples of ‘derivative’ also occur in drugs legislation, some of which stem from the United Nations 1961 Convention and earlier Treaties. There is a commonly-held view that only ‘first-order’ derivatives should be considered; substances that can be created from a parent structure in a single chemical reaction. In other words, ‘derivatives of derivatives’ are excluded. However, some substances related to ecgonine (e.g., 2-carbomethoxytropinone) are clearly convertible to cocaine, even though this may require more than one reaction step. It follows that 2-carbomethoxytropinone could be a controlled drug, a situation that most chemists would regard as perverse. A more extreme example of the complexity of ‘derivative’ is shown by the conversion of thebaine to buprenorphine. Even though, at the time, this required six or more stages, the United States Drug Enforcement Administration successfully argued in a 1986 case that for the purposes of the Controlled Substances Act, the number of steps required was irrelevant; buprenorphine was a derivative of thebaine. Because ‘derivative’ is rarely defined in statutes, the legal status of some substances, such as 2-bromo-LSD, is uncertain. Although a number of definitions of ‘derivative’ can be found in the chemical literature, no single definition is adequate to describe all situations where it occurs in legislation. Unless qualified, it is suggested that the term ‘derivative’ should be avoided in any future legislation.