1-(4-Amino-6,7-dimethoxy-2-chinazolinyl)-4-(2-furoyl)piperazinmonohydrochlorid Chemische Eigenschaften,Einsatz,Produktion Methoden
R-S?tze Betriebsanweisung:
R22:Gesundheitssch?dlich beim Verschlucken.
R36/37/38:Reizt die Augen, die Atmungsorgane und die Haut.
R62:Kann m?glicherweise die Fortpflanzungsf?higkeit beeintr?chtigen.
S-S?tze Betriebsanweisung:
S28:Bei Berührung mit der Haut sofort abwaschen mit viel . . . (vom Hersteller anzugeben).
S36:DE: Bei der Arbeit geeignete Schutzkleidung tragen.
Chemische Eigenschaften
Off-White to Yellow Powder
Verwenden
Prazosin Hydrochloride (Terazosin EP Impurity K) is an antihypertensive. α1-Adrenergic blocker.
Allgemeine Beschreibung
The antihypertensive effectsof prazosin hydrochloride, 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-(2-furoyl)piperazine monohydrochloride(Minipress), are caused by peripheral vasodilation as a resultof its blockade of 1-adrenergic receptors. In ligand-bindingstudies, prazosin hydrochloride has 5,000-fold greater affinityfor α1-receptors than for some α2-adrenergic receptors.
Biologische Aktivit?t
α 1 and α 2B -adrenoceptor antagonist. Also a potent antagonist at the melatonin MT 3 receptor (K i = 10.2 nM). Also available as part of the α 1 -Adrenoceptor Tocriset™ and Mixed Adrenergic Tocriset™ .
Clinical Use
Prazosin hydrochloride is readily absorbed, and plasmaconcentrations reach a peak about 3 hours after administration.Plasma half-life is between 2 and 3 hours. Prazosin hydrochlorideis highly bound to plasma protein; it does notcause adverse reactions, however, with drugs that might bedisplaced from their protein-binding sites (e.g., cardiac glycosides).It may cause severe orthostatic hypertension becauseof its -adrenergic blocking action, which preventsthe reflex venous constriction that is activated when an individualsits up from a prone position.
l?uterung methode
The salt is recrystallised by dissolving it in hot MeOH, adding a small volume of MeOH/HCl (dry MeOH saturated with dry HCl gas) followed by dry Et2O until crystallisation is complete. Dry it in vacuo over solid KOH till the odour of HCl is absent. It has been recrystallised from hot H2O, the crystals are washed with H2O, and the H2O is removed azeotropically with CH2Cl2, and dried in a vacuum. [NMR and IR: Honkanen et al. J Heterocycl Chem 17 797 1980, cf Armarego & Reece Aust J Chem 34 1561 1981.] It is an antihypertensive drug and is an 1-adrenergic antagonist [Brosman et al. Proc Natl Acad Sci USA 82 5915 1985].
1-(4-Amino-6,7-dimethoxy-2-chinazolinyl)-4-(2-furoyl)piperazinmonohydrochlorid Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte