Title: Ahistan
CAS Registry Number: 518-61-6
CAS Name: 10-(Dimethylamino)acetyl-10H-phenothiazine
Additional Names: 10-(N,N-dimethylglycyl)phenothiazine; dacemazine
Molecular Formula: C16H16N2OS
Molecular Weight: 284.38
Percent Composition: C 67.58%, H 5.67%, N 9.85%, O 5.63%, S 11.28%
Literature References: Prepd from phenothiazine and chloroacetyl chloride, followed by treatment with dimethylamine: Cusic, US 2694705 (1954 to Searle).
Properties: Crystals, mp 144-145°.
Melting point: mp 144-145°
Derivative Type: Hydrochloride
Molecular Formula: C16H16N2OS.HCl
Molecular Weight: 320.84
Percent Composition: C 59.90%, H 5.34%, N 8.73%, O 4.99%, S 9.99%, Cl 11.05%
Properties: Crystals, mp 230-231°.
Melting point: mp 230-231°
Therap-Cat: Antihistaminic.
Keywords: Antihistaminic; Tricyclics; Phenothiazines.
Status: This monograph has been retired and is no longer subject to revision or update.
Ajaconine Ajmaline Ajowan Oil Ajugarins Ajulemic Acid

Systematic (IUPAC) name
Clinical data
Legal status  ?
CAS number 518-61-6 N
ATC code None
PubChem CID 68846
ChemSpider 62079 YesY
UNII verifiedrevid = 460112476 88D34UY0QI verifiedrevid = 460112476 N
Chemical data
Formula C16H16N2OS 
Mol. mass 284.376 g/mol
 N (what is this?)

Dacemazine (INN, also known as Ahistan and Histantine)[1] is a phenothiazine derivative which acts as an histamine antagonist at the H1 subtype. First described in 1951, it was never marketed as a drug on its own, although a combination of dacemazine and di-tert-butylnaphthalenesulfonate was sold as an antispasmodic and antitussive under the trade name Codopectyl.[1] It was also assessed as a possible anticancer drug.[2]