Oxazoles are heterocyclic aromatic compounds containing one oxygen atom and one nitrogen atom, separated by a carbon atom. The presence of two heteroatoms (oxygen and nitrogen) provides possible interactions (hydrogen, hydrophobic, van der Waals or dipole bonds) with a wide range of receptors and enzymes. Oxazole rings are valuable heterocyclic scaffolds for the design of novel therapeutics with anticancer, antiviral, antibacterial, anti-inflammatory, neuroprotective, antidiabetic, and antidepressant properties due to their wide range of targets and biological activities.
Compared to quinolines, isoquinolines are also prominent structural motifs present in many biologically significant natural and synthetic compounds. Some well-known isoquinoline alkaloids include the anticancer and anticonvulsant berberine, the vasodilator and antispasmodic drugs papaverine and emetine. In addition to naturally occurring isoquinolines, synthetic analogs have also shown significant biological activity.