Recent Advances in the Synthesis of Pyrroles

Pyrroles are the most prevalent heterocyclic compounds, which are present as the basic cores in many natural products, such as vitamin B12, bile pigments like bilirubin and biliverdin, the porphyrins of heme, chlorophyll, chlorins, bacteriochlorins, and porphyrinogens. The biological activities of compounds having pyrrole analogs include antimicrobial (antibacterial, antifungal), anti-cancer (anti-cytotoxic, antimitotic), anti-tumor, anti-hyperlipidemic, anti-depressant, anti-inflammatory, antihyperglycemic, antiproliferative, anti-HIV and anti-viral activities. Accordingly, significant attention has been paid to develop competent methods for the synthesis of pyrroles with improved yields in short times. This review gives an overview of different methods for the synthesis of pyrrole using easily available precursors using the following routes. Synthesis of monosubstituted pyrrole using 2,5-dimethoxyfuran Synthesis of pyrrole using dialkylacetylene dicarboxylate Synthesis of pyrroles using β-ketoester Synthesis of pyrrole using 1,2-dicarbonyl compounds Synthesis of pyrroles using 1,3-dicarbonyl compounds Synthesis of pyrroles using 1,3-dicarbonyl, amine, nitro and aldehyde group Synthesis of pyrroles using 1,4-dicarbonyl compound and amines Synthesis of pyrrole using enones Synthesis of pyrroles using moieties having acetylene group