The indole ring is one of the most abundant heterocyclic scaffolds found in nature. It is built into
the essential amino acid tryptophan in which the arene component of the indole facilitates π-π interactions,
and the N-H group serving as a hydrogen bond donor to proximal proteinogenic species. Accordingly, the indole
sub-structure forms an essential component of the framework of higher order protein structures. Although
myriad synthetic routes exist to access the indole nucleus including the venerable Fisher indole synthesis
and other named reactions, new methods and modifications to the existing methods remain a key area
of research. Drivers include improving regioselectivity for functionalizing the core, and the need for greener approaches.
Microwave and flow mediated methods have been an area of significant interest to address these issues, and this mini review
will survey recent advances in the field.
Keywords: Flow, indoles, medicinal, microwave, tryptophans.
promotion: free to download
Rights & PermissionsPrintExport