A derivative of ammonium, NH4(+), in which all four of the hydrogens bonded to nitrogen have been replaced with univalent (usually organyl) groups.
| Member | Definition | Role |
|---|
| 4-diphenylacetoxy-1,1-dimethylpiperidinium | A quaternary ammonium salt obtained by formal methylation of the tertiary amino function of 4-diphenylacetoxy-N-methylpiperidine. | 4-DAMP(1+) |
| ambenonium | A symmetrical oxalamide-based bis-quaternary ammonium ion having ethyl and 2-chlorobenzyl groups attached to the nitrogens. | ambenonium |
| atracurium | A diester compound consisting of pentane-1,5-diol with both hydroxyls bearing 3-[1-(3,4-dimethoxybenzyl)-6,7-dimethoxy-2-methyl-3,4-dihydroisoquinolinium-2(1H)-yl]propanoyl groups. | atracurium |
| betaine aldehyde | A quaternary ammonium ion that is nitrogen substituted by three methyl groups and a 2-oxoethyl group. It is an intermediate in the metabolism of amino acids like glycine, serine and threonine. | betaine aldehyde |
| betaine hydrochloride | A quaternary ammonium ion in which the substituents on nitrogen are methyl (three) and carboxymethyl. | N,N,N-trimethylglycinium |
| bethanechol | The carbamic acid ester of 2-methylcholine. A slowly hydrolysed muscarinic agonist with no nicotinic effects, it is used as its chloride salt to increase smooth muscle tone, as in the gastrointestinal tract following abdominal surgery, treatment of gastro-oesophageal reflux disease, and as an alternative to catheterisation in the treatment of non-obstructive urinary retention. | bethanechol |
| bretylium | A quaternary ammonium cation having 2-bromobenzyl, ethyl and two methyl groups attached to the nitrogen. It blocks noradrenaline release from the peripheral sympathetic nervous system, and is used in emergency medicine, cardiology, and other specialties for the acute management of ventricular tachycardia and ventricular fibrillation. | bretylium |
| butyrylthiocholine | A quaternary ammonium ion obtained by the formal condensation of the carboxy group of butyric acid with the thiol group of thiocholine. It is used as a reagent for determination of butyrylcholinesterase activity. | butyrylthiocholine |
| carpronium | A methyl ester resulting from the formal condensation of the carboxy group of 4-(trimethylammonio)butanoic acid with methanol. | carpronium |
| cetyltrimethylammonium ion | A quaternary ammonium ion in which the substituents on nitrogen are one hexadecyl and three methyl groups. | cetyltrimethylammonium ion |
| chlormequat | A quaternary ammonium ion that is choline in which the hydroxy group has been replaced by a chlorine. Its salts (particularly the chloride salt, known as chlormequat chloride) are used as plant growth retardants. | chlormequat |
| cisatracurium | A diester that is the (1R,1'R,2R,2'R)-diastereoisomer of atracurium, a quaternary ammonium ion consisting of pentane-1,5-diol with both hydroxy functions bearing 3-[1-(3,4-dimethoxybenzyl)-6,7-dimethoxy-2-methyl-3,4-dihydroisoquinolinium-2(1H)-yl]propanoyl groups. The active species in the skeletal muscle relaxant cisatracurium besylate. | cisatracurium |
| cyclanoline | A charged berberine alkaloid obtained by N-methylation of (S)-scoulerine. | cyclanoline |
| decamethonium | A quaternary ammonium ion that is a depolarising muscle relaxant whose structure comprises a decane-1,10-diamine core in which each amino group carries three methyl substituents. | decamethonium |
| decyltrimethylammonium | A quarternary ammonium cation having one decyl and three methyl substituents around the central nitrogen. | decyltrimethylammonium ion |
| demecarium | The bis(quaternary ammonium) dication obtained by N,N'-dimethylation of the N,N'-bis[3-(dimethylamino)phenyl carbamate] derivative of 2,13-diazatetradecane. | demarcarium |
| dimethyldodecylbenzylammonium | A quaternary ammonium ion obtained by methylation of N-benzyl-N-methyldodecan-1-amine. | benzododecinium |
| diphthamide | A quaternary ammonium ion that is the derivative of L-histidine having a 4-amino-4-oxo-3-(trimethylammonio)butyl group at the 2-position of the imidazole ring. | diphthamide zwitterion; diphthamide |
| diphthamide | A zwitterionic tautomer of diphthamide having an anionic carboxy group and a protonated primary amino group. | diphthamide zwitterion; diphthamide |
| dodecyltrimethylammonium | A quarternary ammonium cation having one dodecyl and three methyl substituents around the central nitrogen. | dodecyltrimethylammonium ion |
| edrophonium | A quaternary ammonium ion that is N-ethyl-N,N-dimethylanilinium in which one of the meta positions is substituted by a hydroxy group. It is a reversible inhibitor of cholinesterase, with a rapid onset (30-60 seconds after injection) but a short duration of action (5-15 minutes). The chloride salt is used in myasthenia gravis both diagnostically and to distinguish between under- or over-treatment with other anticholinesterases. It has also been used for the reversal of neuromuscular blockade in anaesthesia, and for the management of poisoning due to tetrodotoxin, a neuromuscular blocking toxin found in puffer fish and other marine animals. | edrophonium |
| magnoflorine | An aporphine alkaloid that is (S)-corytuberine in which the nitrogen has been quaternised by an additional methyl group. | (S)-magnoflorine |
| mepiquat | A quaternary ammonium ion has that has two methyl groups and a pentamethylene-1,5-diyl group attached to the nitrogen. Its salts are used as plant growth inhibitors. | mepiquat |
| methacholine | A quaternary ammonium ion in which the nitrogen is substituted with three methyl groups and a 2-acetoxypropyl group. Parasympathomimetic bronchoconstrictor drug used in clinical diagnosis. | methacholine |
| neostigmine | A quaternary ammonium ion comprising an anilinium ion core having three methyl substituents on the aniline nitrogen, and a 3-[(dimethylcarbamoyl)oxy] substituent at position 3. It is a parasympathomimetic which acts as a reversible acetylcholinesterase inhibitor. | neostigmine |
| octyltrimethylammonium | A quarternary ammonium cation having one octyl and three methyl substituents around the central nitrogen. | octyltrimethylammonium ion |
| oxotremorine m | | oxotremorine M |
| pentamethonium | A quarternary ammonium cation that is cadaverine in which the terminal amino hydrogens are substituted methyl groups. Its bromide and iodide salt exhibits ganglionic blocking activity and used in the treatment of hypertension. | pentamethonium |
| phenyltrimethylammonium | A quaternary ammonium ion obtained by methylation of N,N-dimethylaniline. | trimethylphenylammonium |
| propidium | | propidium |
| rocuronium | A 5alpha-androstane compound having 3alpha-hydroxy-, 17beta-acetoxy-, 2beta-morpholino- and 16beta-N-allyllyrrolidinium substituents. | rocuronium |
| succinylcholine | A quaternary ammonium ion that is the bis-choline ester of succinic acid. | succinylcholine |
| tetrabutylammonium | | tetrabutylammonium |
| tetraethylammonium | | tetraethylammonium |
| tetramethylammonium | The simplest quaternary ammonium cation, comprising a central nitrogen linked to four methyl groups. | tetramethylammonium |
| tetrapentylammonium | | tetrapentylammonium |
| tetrapropylammonium | A quarternary ammonium cation with four propyl substituents around the central nitrogen. | tetrapropylammonium |
| tridihexethyl | | tridihexethyl |
| trimethyl(4-oxopentyl)ammonium | A quaternary ammonium ion in which the substituents on nitrogen are methyl (three) and 4-oxopentyl. | N,N,N-trimethyl-N-(4-oxopentyl)ammonium |
| trimethylethylammonium | A quarternary ammonium cation having one ethyl and three methyl substituents around the central nitrogen. | ethyltrimethylammonium |
| trioctylmethylammonium | A quaternary ammonium ion with three octyl groups and one methyl group attached to the nitrogen. | methyltrioctylammonium |
| vecuronium | A 5alpha-androstane compound having 3alpha-acetoxy-, 17beta-acetoxy-, 2beta-piperidino- and 16beta-N-methylpiperidinium substituents. | vecuronium |