Name: 4-Amino-5-methylpyridin-2-ol
CAS No.: 95306-64-2
EINECS No.: 682-818-3
Chemical Formula: C₆H₈N₂O
Molecular Weight: 124.14 g/mol
InChI InChI=1S/C₆H₈N₂O/c1-4-3-8-6(9)2-5(4)7/h2-3H,1H₃,(H₃,7,8,9)
Density 1.137±0.06 g/cm³ (20°C, 760 Torr)
Boiling Point 291.0±33.0°C (760 Torr)
Flash Point 129.8±25.4°C
Water Solubility Insoluble in water, soluble in strongly polar organic solvents
Vapor Pressure 0-0 Pa at 20-50°C
Storage Conditions Store at 2-8°C, protected from light
Sensitivity Sensitive to light
Appearance White to off-white solid powder
Specific Gravity 1.137 (20°C)
Color White to pale yellow
Hazard Symbols GHS06 (Skull), GHS07 (Exclamation Mark)
Risk Terms H301 (Toxic if swallowed), H315 (Skin irritation), H319 (Severe eye irritation), H335 (Respiratory irritation)
Safety Terms: P260, P264, P270, P271, P280, P301+P310, P305+P351+P338, P405, P501
Customs Code: 2933399090 (Other compounds containing non-fused pyridine rings)
II. Properties
4-Amino-5-methyl-2-hydroxypyridine belongs to the pyridine derivative class. Its molecular structure contains both amino and hydroxyl functional groups, giving it a significant basic characteristic. This compound is a white to off-white crystalline solid at room temperature with a high melting point and good thermal stability.
This compound exhibits keto-enol tautomerism; the carbonyl group in its structure can be considered as an enol, and the hydroxyl group can undergo nucleophilic substitution under basic conditions. The presence of electron-donating amino and methyl groups in its molecule increases the electron cloud density of the pyridine ring, enhancing its reactivity.
Regarding solubility, this compound is insoluble in water but soluble in strongly polar organic solvents such as DMSO, DMF, and methanol. Its LogP value is -0.51 (20°C, pH 6.3), indicating some hydrophilicity. The acidity coefficient pKa is 11.90 ± 0.10 (predicted value), indicating weak basicity.
III. Applications
4-Amino-5-methyl-2-hydroxypyridine is an important pharmaceutical intermediate, primarily used in the synthesis of the nonsteroidal selective mineralocorticoid receptor antagonist finerenone. Finerenone is a novel drug developed by Bayer for the treatment of diabetic nephropathy associated with type 2 diabetes.
Furthermore, as a nitrogen-containing heterocyclic ligand, this compound is of significant value in coordination chemistry research. Its multiple coordination sites and flexible coordination modes enable it to react with various metal carbonyl compounds, making it suitable for organometallic chemistry and catalysis research.
In the field of drug development, this compound can also be used to synthesize other pyridine derivatives, serving as a key building block for active pharmaceutical ingredients (APIs) and widely applied in the development of antitumor, antibacterial, and antiviral drugs.
IV. Preparation Method Currently, the commonly used industrial synthetic route uses 2-chloro-4-amino-5-methylpyridine as a starting material, reacting it with potassium alkoxide and adding a suitable catalyst to obtain an intermediate compound. This intermediate is then hydrolyzed in hydrogen bromide solution to finally obtain 4-amino-5-methyl-2-hydroxypyridine.
An improved process involves reacting 3,5,5-trimethyl-4,6-dioxane-2-en-1-one with 3-hydroxypropionitrile to obtain 2-cyanoethyl acetoacetate. This acetoethyl acetoacetate then undergoes a series of Knoevenagel condensation and Hantzsch cyclization reactions with 4-cyano-2-methoxybenzaldehyde and 4-amino-5-methyl-2-hydroxypyridine, finally yielding the target product through O-alkylation, hydrolysis, and ammonolysis.
This synthetic route is simple to operate, with mild reaction conditions, an overall yield of up to 30.8%, a product purity of 99.7%, and an ee value of 99.4%, making it highly valuable for industrial production.
V. Safety Information
Hazard Overview: This compound is a solid, toxic if ingested, irritating to the skin, severely irritating to the eyes, and may cause respiratory irritation.
GHS Hazard Categories:
Acute Oral Toxicity: Category 3
Skin Corrosion/Irritation: Category 2
Severe Eye Damage/Irritation: Category 2A
Specific Target Organ Toxicity – Single Exposure (Respiratory Irritation): Category 3
First Aid Measures:
Eye Contact: Immediately flush thoroughly with plenty of water for at least 15 minutes. If discomfort persists, seek medical attention immediately.
Skin Contact: Immediately remove contaminated clothing and wash skin with plenty of soap and water for at least 15 minutes.
Ingestion: Do not feed to unconscious individuals. Immediately call a doctor or poison control center.
Inhalation: Move the victim to fresh air and keep them in a comfortable resting position.
Fire-Fighting Measures: Combustion may release toxic fumes. Wear a breathing mask and full protective clothing when fighting the fire.
Spill Handling: Isolate the contaminated area and restrict access. Emergency responders should wear dust masks and protective clothing. Prevent the spill from entering the environment.
Storage and Transportation: Store in a cool, well-ventilated warehouse at 2-8°C, away from light. Keep containers tightly closed and the storage area locked. Protect from direct sunlight and rain during transportation. Do not transport with acids, alkalis, oxidants, or food. UN No. 2811, Packaging Category III.
VI. Our Production Advantages and Capacity
Technical Advantages:
Possess proprietary synthetic process routes with mild reaction conditions, high selectivity, and few byproducts.
Utilize advanced purification technology, achieving product purity of over 99.5%, with single impurities controlled below 0.1%.
Strictly adhere to ICH Q3A guidelines, meeting pharmaceutical-grade intermediate quality standards.
Equipped with a comprehensive analytical testing center, featuring advanced instruments such as HPLC, GC-MS, and NMR.
Capacity Guarantee:
Annual production capacity exceeds 50 tons, ensuring stable supply to industrial-scale production needs.
Possess multi-functional production workshops, allowing for flexible adjustments to production plans based on customer requirements.
Ample inventory ensures rapid delivery and shortens customer procurement cycles.
Quality System:
ISO Certified ISO 9001 Quality Management System Certification
Established a comprehensive product traceability system; complete documentation such as COA and MSDS is available for each batch of products.
Complies with GMP requirements and can assist clients with audits and on-site inspections.
Customization Services: Offers flexible packaging sizes from gram to ton (1kg/drum to 25kg/drum).
Can provide products with special purity requirements or specific impurity control according to client needs.
Equipped with a professional technical team to provide synthesis route optimization and technical support services.
Post time: Jun-11-2026
