Decamethonium (Syncurine) is a depolarizing agent made up of 2 quaternary ammoniums with a 10-carbon chain in between, hence the name decamethonium. It's about 2x as potent as succinylcholine, and it is no longer clinically used in the US.
Decamethonium is derived from decamethylenediamine, which is basically just decamethonium but without the extra methyl groups on the nitrogens to make them quaternary ammoniums.
UNDER CONSTRUCTION. DO NOT TRUST THIS PAGE. It has hardly anything. That will change.