Thiophene is a five-membered heterocyclic compound containing a sulfur heteroatom with the molecular formula C4H4S. Thiophene is aromatic and is very similar to benzene; electrophilic substitution reaction is easier than benzene, and it is mainly substituted at the 2-position. Thiophene ring system has certain stability to oxidant.
Nitrogen-containing heterocyclic compounds have a wide range of applications in medicine, organic materials, natural products and other fields, mainly for biologically active molecules. Pyrrolopyrazines contain pyrrole and pyrazine rings as bioactive scaffolds. Compounds containing this scaffold have a wide range of biological activities, such as antibacterial, anti-inflammatory, antiviral, antifungal, antioxidant, antitumor, and kinase inhibition.