Suramin

Suramin is a phenylurea in which each amino group of urea is substituted by a 3-({2-methyl-5-[(4,6,8-trisulfo-1-naphthyl)carbamoyl]phenyl}carbamoyl)phenyl group. It acts as an activator of rabbit skeletal muscle RyR1 and sheep cardiac RyR2 ryanodine receptor channels. Used for over 100 years in treating human African trypanosomiasis, it functions as a ryanodine receptor agonist, GABA-gated chloride channel antagonist, GABA antagonist, apoptosis inhibitor, antineoplastic agent, angiogenesis inhibitor, purinergic P2 receptor antagonist, protein kinase C inhibitor, antinematodal drug, and trypanocidal agent. It belongs to phenylureas, secondary carboxamides, and naphthalenesulfonic acids, and is functionally related to naphthalene-1,3,5-trisulfonic acid. It is the conjugate acid of suramin(6-).