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.
Imidazolines are a class of heterocycles derived from imidazoles by reduction of one of the two double bonds. Three isomers are known, 2-imidazoline, 3-imidazoline and 4-imidazoline. 2 and 3-imidazolines contain imine centers, while 4-imidazolines contain alkene groups. The 2-imidazoline group occurs in several drugs. Imidazolines are an important class of compounds found in many natural and medicinal products. These compounds are also used as intermediates in the synthesis of organic molecules. Furthermore, chiral imidazolines are widely used as organic catalysts for the synthesis of various natural and synthetic organic compounds.