Physicochemical property trends of marketed prodrugs

Many prodrug reviews describe specific examples of the successful application of prodrug technology to produce blockbuster drugs, such as simvastatin, omeprazole, acyclovir and enalapril. These reviews are helpful to understand the previous success stories and case histories of prodrug technology. The aim of the current review seeks to more clearly define quantitative trends in the changes in the physicochemical property parameters between the successful prodrug and the active parent molecule. This information can serve to guide medicinal chemists toward more successful pharmaceutical prodrugs in the future.

Prodrugs for amines

The purpose of this work is to review the published strategies for the production of prodrugs of amines. The review is divided in two main groups of approaches: those that rely on enzymatic activation and those that take advantage of physiological chemical conditions for release of the drugs. A compilation of the most important approaches is presented in the form of a table, where the main advantages and disadvantages of each strategy are also referred.

Monoamine oxidases and related amine oxidases as phase I enzymes in the metabolism of xenobiotics

To date most of the interest in oxidative metabolism of xenobiotics has been devoted to the role of the microsomal cytochrome P-450 system and to establish the basis for classifying and naming P450 enzymes. The contribution of amine oxidases to the metabolism of xenobiotics has been largely neglected, with the exception of the contribution of monoamine oxidases (MAOs) to the metabolism of exogenous tyramine and the studies of the "cheese effect" produced as the result of ingestion of large amounts of tyramine-containing foods under particular conditions. A review of the involvement of the mitochondrial MAOs in drug metabolism was published in 1988. Since that time, considerable additional evidence has appeared in the literature to support the contribution of MAOs to drug metabolism. In addition, the involvement of other amine oxidases in the metabolism of foreign compounds has been established. A second review on the contribution of amine oxidases to the metabolism of xenobiotics was therefore published in 1994. On an arbitrary basis, the heterogeneous class of amine oxidases can be divided into two types according to their prosthetic group: the flavineadenine dinucleotide (FAD)-dependent amine oxidases (Monoamine Oxidase and Polyamine Oxidase) and the amine oxidases not containing FAD (Semicarbazide-sensitive amine oxidases). In this overview, the contributions of these two types in xenobiotic metabolism are considered separately.