Title: Bunazosin
CAS Registry Number: 80755-51-7
CAS Name: 1-(4-Amino-6,7-dimethoxy-2-quinazolinyl)hexahydro-4-(1-oxobutyl)-1H-1,4-diazepine
Additional Names: 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-butyrylhexahydro-1H-1,4-diazepine; 4-amino-6,7-dimethoxy-2-[4-(n-butyryl)homopiperazin-1-yl]quinazoline; DDQ
Molecular Formula: C19H27N5O3
Molecular Weight: 373.45
Percent Composition: C 61.11%, H 7.29%, N 18.75%, O 12.85%
Literature References: Aminoquinazoline derivative with potent hypotensive properties. Prepn: T. Takahashi, H. Sugimoto, BE 806626; eidem, US 3920636 (1974, 1975 to Eisai); alternative prepn: eidem, JP Kokai 75 140474 (1975 to Eisai), C.A. 85, 46769r (1976). In vitro and in vivo studies of adrenergic blocking action and antihypertensive properties: T. Shoji et al., Jpn. J. Pharmacol. 30, 763 (1980); K. Hoshi, S. Fujino, ibid. 427. Antihypertensive effect in volunteers: T. Kawasaki et al., Eur. J. Clin. Pharmacol. 20, 399 (1981). Pharmacokinetics: C. Yamato et al., Xenobiotica 12, 549 (1982).
Derivative Type: Hydrochloride
CAS Registry Number: 52712-76-2
Manufacturers' Codes: E-643
Trademarks: Detantol (Eisai)
Molecular Formula: C19H27N5O3.HCl
Molecular Weight: 409.91
Percent Composition: C 55.67%, H 6.89%, N 17.09%, O 11.71%, Cl 8.65%
Properties: Crystals from methanol/ethanol, mp 280-282°.
Melting point: mp 280-282°
Therap-Cat: Antihypertensive.
Keywords: Antihypertensive; Quinazoline Derivatives.
Bungarotoxins Bunitrolol Bunte Salts Buparvaquone Buphanamine

Systematic (IUPAC) name
Clinical data
AHFS/Drugs.com International Drug Names
Legal status  ?
CAS number 80755-51-7
ATC code None
PubChem CID 2472
ChemSpider 2378 YesY
Chemical data
Formula C19H27N5O3 
Mol. mass 373.44 g/mol
 YesY (what is this?)  (verify)

Bunazosin (INN) is an alpha 1 antagonist. Bunazosin was initially developed to treat benign prostatic hyperplasia (BPH). It has been approved in Japan in a topical form to treat glaucoma. The mechanism of action is a reduction of aqueous outflow through the uveoscleral pathway resulting in lowering the intraocular pressure. It also may act to improve blood flow to the ocular nerve. Systemic Alpha-1 adrenergic receptor antagonists have been implicated in Intraoperative Floppy Iris Syndrome (IFIS). Bunazosin potentially could have the same effect but there has been no research to substantiate this as a risk for cataract surgery.