Acetaminophen CAS#103-90-2
1. Effective Pain Relief: Acetaminophen is a widely used analgesic, known for its ability to effectively reduce pain and fever, making it a staple in over-the-counter pain relief products.
2. Stable Storage: It remains stable at temperatures below 45°C, ensuring longevity and efficacy when stored properly in cool, dry conditions.
3. High Solubility: Acetaminophen is highly soluble in hot water and ethanol, ensuring it dissolves easily for efficient absorption and use in various formulations.
4. Long History of Use: With over a century of clinical use, acetaminophen has a proven track record for safety and effectiveness in treating mild to moderate pain and fever.
The chemical designation of acetaminophen is N-(4-hydroxyphenyl)acetamide, commercially known as paracetamol, which falls under the category of acetanilide antipyretic analgesics. Initially synthesized by Morse in 1878, it was first employed clinically by Von Mering in 1893. The compound gained over-the-counter status in the United States in 1955, while production in China commenced in the late 1950s according to Chemicalbook records.
This substance presents as white crystalline formations or powdered crystals, possessing a melting point range of 168-172°C. It is odorless with a slightly bitter taste, exhibiting high solubility in heated water or ethanol, moderate solubility in acetone, and negligible solubility in cold water and petroleum ether.
Acetaminophen remains stable at temperatures below 45°C. However, when exposed to humid conditions, it undergoes hydrolysis to form para-aminophenol, which subsequently oxidizes further. This degradation process manifests visually as a progressive color change from pink to brown, eventually turning black. Consequently, optimal storage requires cool, dry environments.
Melting point | 168-172 °C(lit.) |
Boiling point | 273.17°C (rough estimate) |
density | 1,293 g/cm3 |
vapor pressure | 0.008Pa at 25℃ |
refractive index | 1.5810 (rough estimate) |
Fp | 11 °C |
storage temp. | Inert atmosphere,Room Temperature |
solubility | ethanol: soluble0.5M, clear, colorless |
form | Crystals or Crystalline Powder |
pka | 9.86±0.13(Predicted) |
color | White |
PH Range | 5.5 - 6.5 (H?O, 20 °C) (saturated solution) |
PH | 5.5-6.5 (H2O, 20℃)(saturated solution) |
Odor | odorless |
explosive limit | 15%(V) |
Water Solubility | 14 g/L (20 ºC) |
Merck | 14,47 |
BRN | 2208089 |
BCS Class | 3,4 |
InChIKey | RZVAJINKPMORJF-UHFFFAOYSA-N |
LogP | 1.098 at 25℃ |
CAS DataBase Reference | 103-90-2(CAS DataBase Reference) |
NIST Chemistry Reference | Acetaminophen(103-90-2) |
IARC | 3 (Vol. 50, 73) 1999 |
EPA Substance Registry System | Acetaminophen (103-90-2) |
Safety Information | |
Hazard Codes | Xn,T,F |
Risk Statements | 22-36/37/38-52/53-36/38-40-39/23/24/25-23/24/25-11 |
Safety Statements | 26-36-61-37/39-22-45-36/37-16-7 |
RIDADR | UN 3077 9/PG III |
WGK Germany | 1 |
RTECS | AE4200000 |
Autoignition Temperature | 540 °C |
TSCA | Yes |
HazardClass | 9 |
PackingGroup | III |
HS Code | 29242930 |
Hazardous Substances Data | 103-90-2(Hazardous Substances Data) |
Toxicity | LD50 in mice (mg/kg): 338 orally (Starmer), 500 i.p. (Dahlin, Nelson |
