Pyrantel
Pyrantel is a carboxamidine that is 1,4,5,6-tetrahydropyrimidine that is substituted at position 1 by a methyl group and at position 2 by an (E)-2-(2-thienyl)vinyl group. It is used, particularly as the embonate [4,4'-methylenebis(3-hydroxy-2-naphthoate)] salt, as an anthelmintic that is effective against intestinal nematodes including threadworms, roundworms and hookworms, and is included in the WHO 'Model List of Essential Medicines'. It has a role as an antinematodal drug. It is a member of thiophenes, a carboxamidine and a member of 1,4,5,6-tetrahydropyrimidines.