Drug Biosynthesis (or Biogenesis)

In the recent past, a good deal of well-deserved importance and recognition have been attributed to the exclusive study of the biochemical pathways that precisely lead to the formulation of ‘active constituents’ otherwise referred to as the secondary constituents mostly employed as drugs. This specific study is normally termed as Drug Biosynthesis or Biogenesis.

As a ‘medicinal chemist’ is required to know the synthesis of chloroquine–an antimalarial drug from pure synthetic compounds, a ‘phytochemist’ is supposed to know the biogenesis of quinine in the cinchona bark. With the advent of isotopically labelled organic compounds known in the early fifties it was quite possible to establish scientifically that the host of amino acids along with their corresponding derivatives more or less acted as precursors of complex alkaloids. However, these logical studies confirmed the earlier hypothesis stated above by Trier in 1912.

Figure 1.6, summarizes the various biosynthetic pathways and their inter-relationships that ultimately lead to the formation of different kinds of secondary constituents (i.e., active constituents) belonging to the plant kingdom which are invariably employed as drugs having potent therapeutic index.