Introduction: Benzofuran moiety constitutes the core of several interesting pharmacologically active natural products. Benzofurans are among feasible potent active inhibitors against many diseases, viruses, microbes, fungus and enzymes. Several series of therapeutically important synthetic and naturally occurring benzofuran-containing compounds are reported in this chapter. Areas covered: The current chapter focuses on the recent applications of benzofuran scaffolds and their wide range of biological activities during 1999 – 2012. The pharmacological areas covered included anti-inflammatory, antitumor, cytotoxic, antimicrobial, antitubercular, antioxidant, antiplasmodial, trypanocidal and insecticidal activities as well as enzyme inhibitory, HCV and HIV inhibitory activities. Expert opinion: The results reported in the chapter indicate that some benzofuran derivatives may be useful as potent drugs. From the structure–activity relationship (SAR), the presence of certain functions like -OH, -OMe in the benzofuran derivatives contributed greatly in increasing the potency of their therapeutic activities when compared with standards. For example, presence of the -OH and -OMe have made some benzofuran compounds more potent HIV-RT inhibitory activity than the standard atevirdine, and more potent antitumor agent when compared with standards (fluorouracil, doxorubicin and cytarabine). In addition, the enzyme aromatase CYP19 inhibitory activity of benzofurans having -OH and -OMe were greater than that observed for the reference arimidex.

Benzofuran moiety is the main component of many biologically active natural and synthetic heterocycles.