Thiobarbituric acid

  • Austranal
  • Bathyran
  • 2-Mercaptobarbituric acid
  • 2-Thio-4,6-dioxypyrimidine
  • 4,6-Dihydroxy-2-mercaptopyrimidine
  • Dihydro-2-thioxo-4,6(1H,5H)-pyrimidinedione
Formula
C4H4N2O2S
Structure
Description
Slightly yellow liquid. With a stench.
Uses
Reagent for measuring the extent of lipid peroxidation in foods.

Registry Numbers and Inventories.
CAS
504-17-6
EC (EINECS/ELINCS)
207-985-8
R 36/37/38
RTECS
CQ7700000
RTECS class
Other
Beilstein/Gmelin
120663
Beilstein Reference
5-24-09-00108
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C4H4N2O2S
Formula mass
144.15
Melting point, °C
235
Boiling point, °C
419
Density
1.661 g/cm3
Solubility in water
Very soluble
pKa/pKb
3.96 (pKa)
Partition coefficient, pKow
-0.81

Hazards and Protection.
Storage
Store in a tightly closed container. Keep under a nitrogen blanket. Store in a cool, dry, well-ventilated area away from incompatible substances.
Handling
Wash thoroughly after handling. Use only in a well ventilated area. Avoid contact with eyes, skin, and clothing. Avoid ingestion and inhalation.
Protection
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Respirators
Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Small spills/leaks
Sweep up or absorb material, then place into a suitable clean, dry, closed container for disposal.
Disposal code
3
Stability
No data.
Incompatibilities
Stttrong oxidizing agents.
Decomposition
Nitrogen oxides, carbon monoxide, oxides of sulfur, carbon dioxide.

Fire.
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. To extinguish fire use water spray, dry chemical, carbon dioxide, or appropriate foam.

Health.
Exposure effects
   Ingestion
Expected to be a low ingestion hazard. May cause nausea and vomiting.
   Inhalation
May cause respiratory tract irritation. The toxicological properties of this substance have not been fully investigated.
   Skin
May cause skin irritation.
   Eyes
May cause eye irritation.

First aid
 
   Ingestion
If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. Get medical aid.
   Inhalation
Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid.
   Skin
Get medical aid. Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes.
   Eyes
Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately.

Transport.
HS Code
2933 59 95