Pharmacological effects
Naphazoline hydrochloride, is commonly used as a vasoconstrictor in the hospital's otorhinolaryngology and ophthalmology ,it is a adrenomimetic drug ,it has a strong effect on contraction of blood vessels and blood pressure elevation,it has inhibition effect on the central nervous system,by contraction of local vascular, it can play an anti-inflammatory and analgesic role in the local inflammatory lesions , and can eliminate congestion due to fatigue or other reasons. Clinically it is used for the treatment of colds, acute and chronic rhinitis, allergic conjunctivitis, allergic and inflammatory nasal congestion embolism. Local long-term use can lead to blood flow reduction in medication area, which causes resistance decreasing , and results in superinfection. It can not be taken orally. Dropping excess liquid or high concentrations can cause poisoning. Care should be taken, especially in children. Infants, hypertension, hyperthyroidism patients should take with caution, atrophic rhinitis patients are banned. The interval time of dropping , is preferably not less than 4 to 6 hours.
The above information is edited by the chemicalbook of Tian Ye.
Chemical Properties
White crystalline powder. Melting point 255-260 ℃. 40 grams of the product can be dissolved in 100 ml of water . It is soluble in alcohol, slightly soluble in chloroform, insoluble in ether and benzene. Odorless, bitter taste.
Uses
This product is a vasoconstrictor. Rat subcutaneous injection is LD50 385 mg/kg.
Production method
By the α-naphthalene acetic acid and ethylene diamine condensation, cyclization ,2-(1-naphthylmethyl) imidazoline (C14H14N2, [835-31-4]) is made , then after salifying, naphazoline hydrochloride is derived . The α-acetic acid and ethylene diamine are added to the reaction pot, stir and heat to 120 ℃, react after 1 hour, then heat to 130 ℃, react for 1 hour. Ethylenediamine and water are distilled ,and after vacuum distillation, collect 180-240 ℃ (1.33-4 kPa) distillate, obtain 2-(1-naphthylmethyl) imidazoline. It is dissolved in a mixture of acetone and ethanol, and at 10-12℃ inlet hydrogen chloride gas to become into a salt, naphazoline hydrochloride crystals is generated .
Chemical Properties
White or almost white, crystalline powder.
Originator
Albalon,Allergan,Australia
Uses
Naphazoline Hydrochloride is a useful synthetic intermediate used in eye drops. A vasoconstrictor.
Definition
ChEBI: Naphazoline is an organic molecular entity.
Manufacturing Process
2.7 parts of naphtyl-(1)-acetiminoethylether (produced from naphthyl-1-
acetonitrile) were dissolved in 12 parts of absolute alcohol. 1 part of
ethylenediamine is then added and the mixture was heated to gentle boiling
while passing it through nitrogen and simultaneously stirring until ammonia
escaped no longer. The alcohol was is then distilled and the residue mixed
with 40 parts of benzene and 1.8 parts of caustic potash. Stirring was
continued for some time whereby the imidazoline base was dissolved in
benzene. The benzene residue, is recrystallized several times from toluene.
The 2-[naphthyl-1-methyl]-imidazoline represented the coloriless crystalls of
melting point 252°-253°C. Its hydrochloride is easily soluble in water.
brand name
Albalon (Allergan); Nafazair
(Bausch & Lomb); Nafazair (Pharmafair); Naphcon
(Alcon); Opcon (Bausch & Lomb); Vasocon (Novartis).
Therapeutic Function
Vasoconstrictor, Nasal decongestant
Biological Activity
α-adrenoceptor agonist; imidazoline receptor agonist; vasoconstrictor.
