Novel Prodrugs for the Treatment of Colonic Diseases Based on 5-Aminosalicylic Acid, 4'-eranyloxyferulic Acid, and Auraptene: Biological Activities and Analytical Assays

A pro-drug is a substance administered in a pharmacologically inactive structure that, once administered, is metabolised in vivo into the corresponding active principle. The rationale for the design of prodrugs is the optimisation of absorption, distribution, metabolism, and excretion (ADME). Moreover these compounds are frequently synthesized to improve bioavailability. 5-Amino salicylic acid (5-ASA) represents one of the most efficient agents for ColoRectal Cancer (CRC) treatment. Its inclusion in natural or semi-synthetic cyclodextrins (CDs) has been extensively studied to enhance drug properties as solubility, stability, and bioavailability. On the other hand, very recently naturally occurring 4'- geranyloxyferulic acid and auraptene were found as novel promising agents for the treatment of colon diseases, like adenomas and adenocarcinomas. In this review we will focus our attention on the reported pharmacological activity and analytical assays for the most representative 5-ASA pro-drugs already in a therapy for the treatment of CRC and on novel prodrugs of 4'-geranyloxyferulic acid and auraptene that were shown to be efficient in vivo as dietary feeding colon cancer chemopreventers in mice.