136-40-3

Usage

Uses

Used in Pharmaceutical Industry:
Phenazopyridine hydrochloride is used as an analgesic for the treatment of urinary tract infections. It is effective in reducing pain associated with these infections when administered at doses of 0.3, 1, and 3 mg/kg in anesthetized rats. It is particularly effective in decreasing the bladder distension-induced firing rate of afferent bladder Aγ-fibers.
Used in Combination Therapy:
Phenazopyridine hydrochloride is often used in combination with other drugs to enhance the analgesic effect and provide more comprehensive relief for patients suffering from urinary tract infections.
Used as a Local Anesthetic:
Due to its topical analgesic effect on the mucosa lining of the urinary tract, Phenazopyridine hydrochloride is used as a local anesthetic in various formulations to alleviate pain and discomfort associated with urinary tract infections.
Used in Azo Dye Industry:
Phenazopyridine hydrochloride, as an azo dye, is utilized in the treatment of urinary tract infections, providing both color and therapeutic benefits.
Used as an Anticonvulsant and Antiepileptic:
In some cases, Phenazopyridine hydrochloride has been used as an anticonvulsant and antiepileptic, although its primary application remains in the treatment of urinary tract infections.
Brand Name:
Phenazopyridine hydrochloride is commercially available under the brand name Pyridium, manufactured by Parke-Davis.

Originator

Phenazopyridine ,AroKor Holdings Inc.

Manufacturing Process

Phenyldiazene chloride reacted with 2,6-diaminopyridine and in the result 2,6diamino-3-(phenylazo)pyridine was obtained.In practice it is usually used as monohydrochloride.

Therapeutic Function

Urinary analgesic, Antiseptic, Diagnostic aid

Air & Water Reactions

Dust can be explosive when suspended in air at specific concentrations. Phenazopyridine hydrochloride may be sensitive to air and light. . Very slightly water soluble.

Reactivity Profile

Phenazopyridine hydrochloride is an azo compound. Azo, diazo, azido compounds can detonate. This applies in particular to organic azides that have been sensitized by the addition of metal salts or strong acids. Toxic gases are formed by mixing materials of this class with acids, aldehydes, amides, carbamates, cyanides, inorganic fluorides, halogenated organics, isocyanates, ketones, metals, nitrides, peroxides, phenols, epoxides, acyl halides, and strong oxidizing or reducing agents. Flammable gases are formed by mixing materials in this group with alkali metals. Explosive combination can occur with strong oxidizing agents, metal salts, peroxides, and sulfides.

Fire Hazard

Flash point data for Phenazopyridine hydrochloride are not available. Phenazopyridine hydrochloride is probably combustible.

Clinical Use

Phenazopyridine hydrochloride, 2,6-diamino-3-(phenylazopyridinehydrochloride (Pyridium), is a brick-red, finecrystalline powder. It is slightly soluble in alcohol, in chloroform,and in water.Phenazopyridine hydrochloride was formerly used asa urinary antiseptic. Although it is active in vitro againststaphylococci, streptococci, gonococci, and E. coli, it has nouseful antibacterial activity in the urine. Thus, its presentutility lies in its local analgesic effect on the mucosa of theurinary tract.Usually, phenazopyridine is given in combination withurinary antiseptics. For example, it is available as Azo-Gantrisin, a fixed-dose combination with the sulfonamide antibacterialsulfisoxazole, and as Urobiotic, a combination withthe antibiotic oxytetracycline and the sulfonamide sulfamethizole. The drug is rapidly excreted in the urine, towhich it gives an orange-red color. Stains in fabrics may beremoved by soaking in a 0.25% solution of sodium dithionite.

Safety Profile

Confirmed carcinogen with experimental carcinogenic and tumorigenic data. A poison by intraperitoneal and intravenous routes. Moderately toxic by ingestion. Human systemic effects by ingestion: somnolence, cyanosis, dlarrhea, nausea or vomiting, anuria or decreased urine volume, normocytic anemia, methemoglobinemiacarboxyhemoglobinemia, dehydration, changes in blood sodium levels. Mutation data reported. When heated to decomposition it emits very toxic fumes of NOx and HCl

Carcinogenicity

Phenazopyridine hydrochloride is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity fromstudies in experimental animals.

InChI:InChI=1/C11H11N5.ClH/c12-10-7-6-9(11(13)14-10)16-15-8-4-2-1-3-5-8;/h1-7H,(H4,12,13,14);1H

Synthetic route

2,6-Diaminopyridine (141-86-6) + aniline (62-53-3) → 3-phenyldiazenylpyridine-2,6-diamine monohydrochloride (136-40-3)

Conditions	Yield
With hydrogenchloride; sodium nitrite 1) 10 min, ice-cooled, 2) r. t., 20 min; Yield given. Multistep reaction;

3-phenyldiazenylpyridine-2,6-diamine monohydrochloride (136-40-3) → pyridium (94-78-0)

Conditions	Yield
With potassium carbonate In water; ethyl acetate at 20℃; for 0.5h;	92%
With sodium hydroxide In water

salicylaldehyde (90-02-8) + 3-phenyldiazenylpyridine-2,6-diamine monohydrochloride (136-40-3) → 2-({[6-amino-5-(2-phenyldiazenyl)pyridin-2-yl]imino}methyl)phenol hydrochloride (1454284-39-9)

Conditions	Yield
In ethanol for 2h;	86%

3-phenyldiazenylpyridine-2,6-diamine monohydrochloride (136-40-3) + 5-Nitrosalicylaldehyde (97-51-8) → 2-({[6-amino-5-(2-phenyldiazenyl)pyridin-2-yl]imino}methyl)-4-nitrophenol hydrochloride (1454284-41-3)

Conditions	Yield
In ethanol for 2h;	86%

2-hydroxy-5-methoxybenzaldehyde (672-13-9) + 3-phenyldiazenylpyridine-2,6-diamine monohydrochloride (136-40-3) → 2-({[6-amino-5-(2-phenyldiazenyl)pyridin-2-yl]imino}methyl)-4-methoxyphenol hydrochloride (1454284-40-2)

Conditions	Yield
In ethanol for 2h;	85%

3-phenyldiazenylpyridine-2,6-diamine monohydrochloride (136-40-3) + 2-hydroxynaphthalene-1-carbaldehyde (708-06-5) → 1-({[6-amino-5-(2-phenyldiazenyl)pyridin-2-yl]imino}methyl)-2-naphthol hydrochloride (1454284-42-4)

Conditions	Yield
In ethanol for 2h;	83%

3-phenyldiazenylpyridine-2,6-diamine monohydrochloride (136-40-3) → pyrido[3,4-c]cinnoline-2,4-diamine + N3-phenylpyridine-2,3,4,6-tetraamine + 2,6-diamino-1-(4-aminophenyl)pyridin-4(1H)-one + 2,3,6-triaminopyridine (4318-79-0)

Conditions	Yield
In methanol for 12h; UV-irradiation;	A 35% B 15% C 5% D 12%

3-phenyldiazenylpyridine-2,6-diamine monohydrochloride (136-40-3) → Blue Fluorophor (4324-87-2)

Conditions	Yield
With ammonium hydroxide; copper(II) sulfate In water for 6h; Heating;

3-phenyldiazenylpyridine-2,6-diamine monohydrochloride (136-40-3) → C8H5NO2*C11H11N5 (1374137-75-3)

Conditions	Yield
Multi-step reaction with 2 steps 1: sodium hydroxide / water 2: ethanol / 24 h / 60 °C View Scheme

3-phenyldiazenylpyridine-2,6-diamine monohydrochloride (136-40-3) → C8H8O3*C11H11N5 (1374137-77-5)

Conditions	Yield
Multi-step reaction with 2 steps 1: sodium hydroxide / water 2: ethanol / 24 h / 20 °C View Scheme

3-phenyldiazenylpyridine-2,6-diamine monohydrochloride (136-40-3) → C7H5NO3S*C11H11N5 (1374137-78-6)

Conditions	Yield
Multi-step reaction with 2 steps 1: sodium hydroxide / water 2: ethanol View Scheme

3-phenyldiazenylpyridine-2,6-diamine monohydrochloride (136-40-3) → 2ClH*C22H18N10

Conditions	Yield
With multi-walled carbon nanotubes modified with ZnCrFeO4 magnetic nanoparticles (MWCNTs/ZnCrFeO4/CPE) In aq. phosphate buffer pH=2; Reagent/catalyst; Electrochemical reaction;

Upstream product

• 141-86-6 2.6-diaminopyridine 
• 100-34-5 benzene diazonium chloride 
• 62-53-3 aniline 

Downstream Products

• 4324-87-2 Blue Fluorophor 
• 94-78-0 pyridium 
• 1374137-75-3 C₈H₅NO₂*C₁₁H₁₁N₅ 
• 1374137-77-5 C₈H₈O₃*C₁₁H₁₁N₅ 
• 1374137-78-6 C₇H₅NO₃S*C₁₁H₁₁N₅ 
• 1454284-39-9 2-({[6-amino-5-(2-phenyldiazenyl)pyridin-2-yl]imino}methyl)phenol hydrochloride 
• 1454284-40-2 2-({[6-amino-5-(2-phenyldiazenyl)pyridin-2-yl]imino}methyl)-4-methoxyphenol hydrochloride 
• 1454284-41-3 2-({[6-amino-5-(2-phenyldiazenyl)pyridin-2-yl]imino}methyl)-4-nitrophenol hydrochloride 
• 1454284-42-4 1-({[6-amino-5-(2-phenyldiazenyl)pyridin-2-yl]imino}methyl)-2-naphthol hydrochloride 

Related news

Experimental design of membrane sensor for selective determination of Phenazopyridine hydrochloride (cas 136-40-3) based on computational calculations09/30/2019

Computational study has been done electronically and geometrically to select the most suitable ionophore to design a novel sensitive and selective electrochemical sensor for phenazopyridine hydrochloride (PAP). This study has revealed that sodium tetraphenylbarate (NaTPB) fits better with PAP th...detailed