Amezinium metilsulfate

☆ Save On Wikipedia ↗
Amezinium metilsulfate
Clinical data
AHFS/Drugs.comInternational Drug Names
Routes of
administration		Oral
ATC code
Legal status
Legal status
  • In general: ℞ (Prescription only)
Identifiers
  • 6-Methoxy-1-phenylpyridazin-1-ium-4-amine; methyl sulfate
CAS Number
PubChem CID
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
CompTox Dashboard (EPA)
ECHA InfoCard100.045.665
Chemical and physical data
FormulaC12H15N3O5S
Molar mass313.33 g·mol−1
3D model (JSmol)
  • COC1=[N+](N=CC(=C1)N)C2=CC=CC=C2.COS(=O)(=O)[O-]
  • InChI=1S/C11H11N3O.CH4O4S/c1-15-11-7-9(12)8-13-14(11)10-5-3-2-4-6-10;1-5-6(2,3)4/h2-8,12H,1H3;1H3,(H,2,3,4) checkY
  • Key:ZEASXVYVFFXULL-UHFFFAOYSA-N checkY
 ☒NcheckY (what is this?)  (verify)

Amezinium metilsulfate (INNTooltip International Nonproprietary Name, sold under the brand name Regulton, is a sympathomimetic drug which is widely used in the treatment of orthostatic hypotension in Japan.[1][2][3][4]

Pharmacology

Pharmacodynamics

Amezinium metilsulfate has a unique mechanism of action of acting as a dual monoamine oxidase inhibitor (MAOI) and norepinephrine reuptake inhibitor (NRI).[3][2][4]

Chemistry

Synthesis

This drug is made from 2-butyne-1,4-diol starting material with chloridazon as an intermediate.

Thieme ChemDrug Synthesis:[5][6][7]

The halogenation of 2-butyne-1,4-diol (1) with chlorine gives mucochloric acid (2). Treatment with phenylhydrazine (3) gives 1-phenyl-4,5-dichloro-6-pyridazone (4). Addition of ammonia leads to chloridazon (5). Catalytic hydrogenation yields 5-amino-2-phenylpyridazin-3-one (6). Alkylation with dimethyl sulfate completes the synthesis of amezinium metisulfate (7).

See also

References

  1. "Delving into the Latest Updates on Amezinium Metilsulfate with Synapse". Synapse. 28 October 2025. Retrieved 13 March 2026.
  2. Deftereos SN, Dodou E, Andronis C, Persidis A (July 2012). "From depression to neurodegeneration and heart failure: re-examining the potential of MAO inhibitors". Expert Rev Clin Pharmacol. 5 (4): 413–425. doi:10.1586/ecp.12.29. PMID 22943121. Amezinium metilsulfate (risumic, supratonin, amezinin and ryzmilate) is an indirectly acting sympathomimetic drug available in Japan, which reversibly inhibits intraneuronal MAO-A and MAO-B, as well as the reuptake of NE at postganglionic sympathetic terminals [120,121]. Amezinium is indicated for the treatment of essential hypotension, orthostatic hypotension and hypotension during dialysis [208].
  3. Oldenburg O, Kribben A, Baumgart D, Philipp T, Erbel R, Cohen MV (December 2002). "Treatment of orthostatic hypotension". Curr Opin Pharmacol. 2 (6): 740–747. doi:10.1016/s1471-4892(02)00213-8. PMID 12482740. Amezinium metilsulfate is one of the most popular drugs in Japan for the treatment of OH. It has a unique mechanism of vasoconstriction. The drug inhibits monoamine oxidase (MAO) activity and norepinephrine (noradrenaline) uptake, and, therefore, enhances norepinephrine activity resulting in an increase in blood pressure [59]. Amezinium is especially recommended [60,61] in selected patients with asympathotonic (deficiency of sympathetic stimulation) OH [62••].
  4. Kita K, Hirayama K (July 1988). "Treatment of neurogenic orthostatic hypotension with amezinium metilsulfate, a new indirect sympathomimetic drug". Neurology. 38 (7): 1095–1099. doi:10.1212/wnl.38.7.1095. PMID 3386828.
  5. Unterhalt B (1981). "Amezinium metilsulfate". Drugs of the Future. 6 (4): 207. doi:10.1358/dof.1981.006.04.199346.
  6. Reicheneder F, Burger TF, König H, Kropp R, Lietz H, Thyes M, Wiersdorff WW (1981). "Amezinium. Synthesis and radioactive labelling". Arzneimittel-Forschung. 31 (9a): 1529–1533. PMID 7197967.
  7. Beljean M, Pays M. "Heterocyclic hydrazines and hydrazones. II. Synthesis of hydrazino derivatives and of hydrazones in the thiazolo[4,5-d]pyridazin-7-ones". Bulletin de la Société Chimique de France. 12 (2): 3324–3330.