Thiophenes are a class of heterocyclic
aromatic compounds based on a five-membered ring
made up of one sulfur and four carbon atoms. The
thiophene nucleus is well established as an interesting
moiety, with numerous applications in a variety of
different research areas. Naturally occurring thiophenes are characteristic secondary metabolites
derived from plants belonging to the family Asteraceae, such as Tagetes, Echinops, Artemisia, Balsamorhiza, Blumea, Pluchea, Porophyllum and
Eclipta. Furthermore, naturally occurring thiophenes
are generally composed of one to five thiophene rings
that are coupled together through their a-carbons, and
carry alkyl chains on their free ortho-positions.
Thiophene-containing compounds possess a wide
range of biological properties, such as antimicrobial,
antiviral, HIV-1 protease inhibitor, antileishmanial,
nematicidal, insecticidal, phototoxic and anticancer
activities. This review focuses on naturally occurring
thiophene derivatives; their sources, physical and
spectral data, and biological activities.