Isonicotinic acid
Also known as: 4-Pyridinecarboxylic acid, pyridine-4-carboxylic acid, 4-Carboxypyridine, Pyridine-4-carboxylic acid, 4-Picolinic acid, g-Pyridinecarboxylic acid, g-picolinic acid
Isonicotinic acid (CAS 55-22-1) is a compound in the Organic Acids category listed in the Jingsj chemical database. It has the molecular formula C6H5NO2 and a molecular weight of 123.109 g/mol. Key properties include a melting point of ≥300 °C(lit.), a boiling point of 396.0±15.0 °C at 760 mmHg, a density of 1.3±0.1 g/cm3 and a flash point of 193.3±20.4 °C. It is classified under GHS with signal word Warning and hazard statements H315 — Causes skin irritation, H319 — Causes serious eye irritation and H335 — May cause respiratory irritation. No supplier offers are currently listed; request a quote. Record last updated Nov 3, 2026.
- CAS No.
- 55-22-1
- Jingsj CID
- J-30605-8
- Molecular Formula
- C6H5NO2
- Molecular Weight
- 123.109 g/mol
- Category
- Organic Acids
- Last updated
- 11/3/2026
No offers for this compound yet.
Request a quotePhysicochemical Properties
| Melting Point | ≥300 °C(lit.) |
|---|---|
| Boiling Point | 396.0±15.0 °C at 760 mmHg |
| Density | 1.3±0.1 g/cm3 |
| Flash Point | 193.3±20.4 °C |
| Exact Mass | 123.032028 |
| PSA | 50.19000 |
| LogP | 0.54 |
| Vapor Pressure | 0.0±1.0 mmHg at 25°C |
| Refractive Index | 1.571 |
| Additional Property | 5.2 g/L (20 ºC) |
GHS Safety & Compliance
- H315 — Causes skin irritation
- H319 — Causes serious eye irritation
- H335 — May cause respiratory irritation
Activity & Biological Data
| Additional Information | [1]. Seng KY, et al. Population pharmacokinetic analysis of isoniazid, acetylisoniazid, and isonicotinic acid in healthy volunteers. Antimicrob Agents Chemother. 2015 Nov;59(11):6791-9. |
|---|
Customs & Trade Information
| HS Code | 2933399090 |
|---|---|
| Summary | 2933399090. other compounds containing an unfused pyridine ring (whether or not hydrogenated) in the structure. VAT:17.0%. Tax rebate rate:13.0%. . MFN tariff:6.5%. General tariff:20.0% |
Frequently Asked Questions
What is the CAS number of Isonicotinic acid?
The CAS number of Isonicotinic acid is 55-22-1.
What are the molecular formula and molecular weight of Isonicotinic acid?
Isonicotinic acid has molecular formula C6H5NO2 and molecular weight 123.109 g/mol.
Is Isonicotinic acid hazardous?
Isonicotinic acid has GHS signal word Warning and hazard statements H315 — Causes skin irritation; H319 — Causes serious eye irritation; H335 — May cause respiratory irritation.
What are the upstream and downstream products of Isonicotinic acid?
For Isonicotinic acid, Upstream Products: Isonicotinamide, 4-Methylpyridine, Isonicotinic Acid N-Oxide; Downstream Products: 4-Amino-5-(pyridin-4-yl)-4H-1,2,4-triazole-3-thiol, Isoniazid, 1,2-Diisonicotinoylhydrazine.
Data compiled from public chemical databases such as PubChem and supplier catalogs; supplier offers are provided by suppliers.
Last updated:
How to cite: Jingsj. "Isonicotinic acid (CAS 55-22-1)". Jingsj Chemical Database. https://www.jingsj.com/compound/J-30605-8 (accessed 2026-11-09).
Data for reference only; verify product details with suppliers before purchase.