Skeletal muscle relaxants Pharmacokinetics Indications Chlorzoxazone synthesis Medicine interactions Side effects Uses Category Toxicity grading Acute toxicity Flammability and hazard properties Storage characteristics Extinguishing agent
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Skeletal muscle relaxants Pharmacokinetics Indications Chlorzoxazone synthesis Medicine interactions Side effects Uses Category Toxicity grading Acute toxicity Flammability and hazard properties Storage characteristics Extinguishing agent
Chlorzoxazone Structure
  • CAS No.95-25-0
  • Chemical Name:Chlorzoxazone
  • CBNumber:CB0392987
  • Molecular Formula:C7H4ClNO2
  • Formula Weight:169.57
  • MOL File:95-25-0.mol
Chlorzoxazone Property
  • Melting point: :191-192 °C(lit.)
  • Density  :1.3771 (rough estimate)
  • refractive index  :1.5557 (estimate)
  • storage temp.  :-20°C Freezer
  • solubility  :DMSO: soluble50mg/mL, clear
  • form  :Powder
  • pka :pKa 8.3 (Uncertain)
  • color  :white to off-white
  • Water Solubility  :0.1 g/100 mL
  • Merck  :14,2194
  • CAS DataBase Reference :95-25-0(CAS DataBase Reference)
  • EWG's Food Scores :1
  • FDA UNII :H0DE420U8G
  • NIST Chemistry Reference :Chlorzoxazone(95-25-0)
  • EPA Substance Registry System :Chlorzoxazone (95-25-0)
  • Hazard Codes  :Xn,T,Xi
  • Risk Statements  :22-36/37/38-20/21/22
  • Safety Statements  :26-36-24/25-37/39
  • WGK Germany  :3
  • RTECS  :DM5250000
  • Hazard Note  :Toxic/Irritant
  • TSCA  :Yes
  • HazardClass  :IRRITANT
  • HS Code  :29349990
  • Toxicity :LD50 in mice (mg/kg): 3650 orally, 380 i.p. (suspensions); 440 orally, 183 i.p. (solns of Na salt) (Hofrichter)
Hazard and Precautionary Statements (GHS)
  • Symbol(GHS)
  • Signal wordWarning
  • Hazard statements H301-H302-H315-H319-H335
  • Precautionary statements P301+P312+P330-P305+P351+P338-P261-P280a-P301+P310a-P405-P501a-P264-P270-P280-P302+P352+P332+P313+P362+P364-P305+P351+P338+P337+P313-P501
Chlorzoxazone Price More Price(15)
  • Brand: Sigma-Aldrich
  • Product number: C4397
  • Product name : Chlorzoxazone
  • Purity: 
  • Packaging: 25g
  • Price: $74.9
  • Updated: 2020/08/18
  • Buy: Buy
  • Brand: Sigma-Aldrich
  • Product number: 1130505
  • Product name : Chlorzoxazone
  • Purity: United States Pharmacopeia (USP) Reference Standard
  • Packaging: 350mg
  • Price: $366
  • Updated: 2020/08/18
  • Buy: Buy
  • Brand: TCI Chemical
  • Product number: C2237
  • Product name : Chlorzoxazone
  • Purity: >98.0%(GC)(T)
  • Packaging: 25g
  • Price: $36
  • Updated: 2020/06/24
  • Buy: Buy
  • Brand: TCI Chemical
  • Product number: C2237
  • Product name : Chlorzoxazone
  • Purity: >98.0%(GC)(T)
  • Packaging: 250g
  • Price: $180
  • Updated: 2020/06/24
  • Buy: Buy
  • Brand: Alfa Aesar
  • Product number: B24507
  • Product name : 5-Chloro-2(3H)-benzoxazolone, 99%
  • Purity: 
  • Packaging: 250g
  • Price: $166
  • Updated: 2020/06/24
  • Buy: Buy

Chlorzoxazone Chemical Properties,Usage,Production

  • Skeletal muscle relaxants Chlorzoxazone is an orally active central skeletal muscle relaxant with its chemical structure being completely different with all the other muscle relaxants. It, mainly through acting on the central cerebral cortex and the spinal cord, inhibits the multi-synaptic reflection related to muscle spasms and produces muscle relaxation, further relieves the spasm caused pain and increase the flexibility of the muscles involved. Acetaminophen belongs to non-steroidal anti-inflammatory drugs and may mainly exert the analgesic and antipyretic effects through the inhibition of prostaglandin synthesis. Muscle relaxation studies through mouse traction test have demonstrated that the compound Chlorzoxazone showed a dose-dependent muscle relaxant effect with excellent protective effect on the strychnine-induced seizures in mice. The existence of paracetamol in the compound chlorzoxazone tablets can further enhance the effect of chlorzoxazone. Hot plate analgesic tests have showed the compound chlorzoxazone has a significant analgesic effect in a dose-dependent manner. It also has antagonism effect on the painful writhing of mice caused by antimony potassium tartrate in a good dose-response relationship. Test results have showed that acetaminophen and chlorzoxazone analgesic synergy.
    This information is edited by Xiongfeng Dai from Chemicalbook.
  • Pharmacokinetics This product can be completely absorbed by the digestive tract with the plasma concentration reaching peak at 1.5-2 hours. It is distributed in muscle, kidney, liver, brain and fat. After 6 hours, the drug concentration decreases significantly. Almost all of the goods can subject to in vivo catabolism with the elimination half-life being about 1 hour.
    This information is edited by Xiongfeng Dai from Chemicalbook.
  • Indications Chlorzoxazone is suitable for the treatment of various kinds of acute and chronic soft tissue (muscles, ligaments and fascia) sprain, contusion, muscle pain after exercise, pain caused by muscle strain and the muscle spasms caused by the central nervous system lesions as well as chronic fasciitis.
  • Chlorzoxazone synthesis Take 2, 5-dichloro-nitrobenzene as raw material; go through hydrolysis, reduction reaction to give 2-amino-4-chloro-phenol, followed by cyclization reaction in hydrochloric acid to obtain the finished product of Chlorzoxazone with the total yield being 84%.

  • Medicine interactions When this product is used in combination with central inhibitory drugs such as phenothiazines and barbituric acid derivative and monoamine oxidase inhibition drugs, we should reduce the usage amount of this product.
  • Side effects There may be occasionally mild drowsiness, dizziness, nausea, heart palpitations, weakness, abdominal pain and other reactions. This drug should be discontinued in case of allergic reactions. These adverse reactions are generally mild and may go away automatically or alleviated after stopping using this drug.
  • Uses It can be used as pharmaceutical intermediates.
    It can be used as central muscle relaxants, for being applied to a variety of soft tissue pain caused by chronic sprain, contusion and muscle strain as well as muscle spasms and pain caused by the central nervous system and so on.
  • Category Toxic substances.
  • Toxicity grading Highly toxic.
  • Acute toxicity Oral-rat LD50: 763 mg/kg; Oral-Mouse LD50: 440 mg/kg.
  • Flammability and hazard properties Thermal decomposition can release nitrogen oxides and chlorides smoke.
  • Storage characteristics Treasury: ventilated, low temperature and dry; store it separately from food raw materials.
  • Extinguishing agent Water, carbon dioxide, foam, powder.
  • Chemical Properties White to Off-White Solid
  • Originator Paraflex ,McNeil, US ,1958
  • Uses Chlorzoxazone is a benzoxazolone derivative that causes skeletal muscle relaxation and blocks spasticity in clinical studies. Chlorzoxazone enhances small and intermediate conductance calcium-activated potassium channels (EC50s = 87 and 98 μM for KCa2.2 and KCa3.1, respectively). The cytochrome P450 isoform CYP2E1 converts chlorzoxazone to 6-hydroxy chlorzoxazone . The urinary excretion of this 6-hydroxy metabolite is often used as a probe of CYP2E1 activity in studies of hepatotoxicity.
  • Uses Muscle relaxant (skeletal)
  • Uses For the relief of discomfort associated with acute painful musculoskeletal conditions.
  • Definition ChEBI: A member of the class of 1,3-benzoxazoles that is 1,3-benzoxazol-2-ol in which the hydrogen atom at position 5 is substituted by chlorine. A centrally acting muscle relaxant with sedative properties, it is used for the symptomatic treatment of painful mus le spasm.
  • Manufacturing Process A solution of 16.9 g (0.1 mol) of 2-amino-5-chlorobenzoxazole in 200 ml of 1 N HCl is refluxed until precipitation is complete. The resulting solid is collected
    by filtration, dissolved in 200 ml of 1 N NaOH and the solution extracted with 50 ml of ether. Acidification of the alkaline solution gives a precipitate which is purified by crystallization from acetone to give 2-hydroxy-5-chlorobenzoxazole melting at 191° to 191.5°C.
  • brand name Paraflex (Ortho-McNeil).
  • Therapeutic Function Muscle relaxant
Chlorzoxazone Preparation Products And Raw materials
Raw materials
Preparation Products
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95-25-0, ChlorzoxazoneRelated Search:
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  • Chloroxazone
  • 5-Chloro-2(3H)-benzoxazolone, 5-Chloro-2-hydroxybenzoxazole
  • Chloroxazone,98%
  • 5-Chloro-2-benzoxazolinoone
  • 5-chloro-2(3h)-benzoxazolone
  • 2(3H)-Benzoxazolone, 5-chloro-
  • 2-Benzoxazolinone, 5-chloro-
  • 2-Hydroxy-5-chlorobenzoxazole
  • 5-Chlorbenzoxazolin-2-on
  • 5-Chloro-1,3-benzoxazol-2(3H)-one
  • 5-chloro-2(3h)-benzoxazolon
  • 5-chloro-2-benzoxazolinon
  • 5-Chloro-2-benzoxazolol
  • 5-Chloro-3(H)-2-benzoxazolone
  • 5-Chlorobenzoksazolinon-2
  • 5-Chlorobenzoksazolon-2
  • 5-Chlorobenzoxazol-2-one
  • 5-Chlorobenzoxazolidone
  • 5-Chlorobenzoxazolinone
  • 5-Chlorobenzoxazolone
  • 5-Chloro-2-benzoxazolone (Chlorzoxazone)
  • Chlorzoxazone,5-Chloro-2(3H)-benzoxazolone, 5-Chloro-2-hydroxybenzoxazole
  • Chlorzoxazone (350 mg)
  • Chlorzoxazone (500 mg)
  • Chlorzoxazone-13C,15N,D2
  • 5-chloro-2,3-dihydro-1,3-benzoxazol-2-one
  • Chloroxazone, 98% 25GR