5-chloro-2,3-dihydro-1,3-benzoxazol-2-one

• ChemBase ID: 240
• Molecular Formular: C7H4ClNO2
• Molecular Mass: 169.56516
• Monoisotopic Mass: 168.99305605
• SMILES: Clc1cc2[nH]c(=O)oc2cc1
• Canonical SMILES: Clc1ccc2c(c1)[nH]c(=O)o2
• InChI: InChI=1S/C7H4ClNO2/c8-4-1-2-6-5(3-4)9-7(10)11-6/h1-3H,(H,9,10)
• InChIKey: TZFWDZFKRBELIQ-UHFFFAOYSA-N

NAMES AND DATABASE IDS

Names

• IUPAC name: 5-chloro-2,3-dihydro-1,3-benzoxazol-2-one
• IUPAC Traditional name: chlorzoxazone; 5-chloro-3H-1,3-benzoxazol-2-one
• Brand Name: Biomioran; EZE-DS; Escoflex; Flexazone; Mioran; Miotran; Myoflexin; Myoflexine; Neoflex; Paraflex; Parafon Forte Dsc; Pathorysin; Relaxazone; Remular; Remular-S; Solaxin; Strifon Forte Dsc; Usaf Ma-10
• Synonyms: Chloroxazone; Chlorzoxazon; Chlorzoxane; Chlorzoxazone; 5-Chloro-1,3-benzoxazol-2(3H)-one; 5-Chloro-3H-benzoxazol-2-one; 5-Chloro-2,3-dihydro-2-oxo-1,3-benzoxazole; 5-Chloro-1,3-benzoxazol-2(3H)-one 99%; 5-Chloro-2(3H)-benzoxazolone; Chlorzoxazone; 5-Chloro-2-hydroxybenzoxazole; 5-Chloro-2-benzoxazolinone; Chlorzoxazone; 5-Chloro-2(3H)-benzoxazolone; 5-chloro-2(3h)-benzoxazolone; 5-氯-2(3H)-苯并噁唑酮

Database IDs

• CAS Number: 95-25-0
• EC Number: 202-403-9
• MDL Number: MFCD00005717
• Merck Index: 142194
• PubChem SID: 160963703; 24277702; 46507755
• PubChem CID: 2733

CALCULATED PROPERTIES

JChem

• Acid pKa: 9.39075
• H Acceptors: 2
• H Donor: 1
• LogD (pH = 5.5): 1.9356183
• LogD (pH = 7.4): 1.9314784
• Log P: 1.9356713
• Molar Refractivity: 41.069 cm^3
• Polarizability: 15.259254 Å^3
• Polar Surface Area: 38.33 Å^2
• Rotatable Bonds: 0
• Lipinski's Rule of Five: true

ALOGPS 2.1

• Log P: 2.09
• LOG S: -1.76
• Solubility (Water): 2.96e+00 g/l

PROPERTIES

Physical Property

• Solubility: 1000 mg/L
• Melting Point: 184 - 186°C; 189-192°C; 191-192 °C(lit.); 191-192°C
• Hydrophobicity(logP): 1.6; 1.871

Safety Information

• Storage Condition: Room Temperature (15-30°C)
• Storage Warning: Harmful/Irritant; IRRITANT
• RTECS: DM5250000
• European Hazard Symbols: X; Harmful (Xn)
• German water hazard class: 3
• Risk Statements: 22-36/37/38; R:22-36/37/38
• Safety Statements: 26-36; 26-36/37; S:25-26-36/37/39
• TSCA Listed: false; 是
• GHS Pictograms: GHS06; GHS07
• GHS Signal Word: Warning
• GHS Hazard statements: H301-H315-H319-H335; H302-H315-H319-H335
• GHS Precautionary statements: P261-P301+P310-P305+P351+P338-P302+P352-P405-P501A; P261-P305 + P351 + P338
• Personal Protective Equipment: dust mask type N95 (US), Eyeshields, Gloves

Pharmacology Properties

• Target: Others

Product Information

• Purity: 95%; 97%; 98%; 99%
• Salt Data: Free Base

DETAILS

MP Biomedicals - 02154979

(5-Chloro-2-hydroxybenzoxazole) Crystalline

DrugBank - DB00356

• Drug Groups: approved
• Description: A centrally acting central muscle relaxant with sedative properties. It is claimed to inhibit muscle spasm by exerting an effect primarily at the level of the spinal cord and subcortical areas of the brain. (From Martindale, The Extra Pharmacopoea, 30th ed, p1202)
• Indication: For the relief of discomfort associated with acute painful musculoskeletal conditions.
• Pharmacology: Chlorzoxazone, a synthetic compound, inhibits antigen-induced bronchospasms and, hence, is used to treat asthma and allergic rhinitis. Chlorzoxazone is used as an ophthalmic solution to treat conjunctivitis and is taken orally to treat systemic mastocytosis and ulcerative colitis. Chlorzoxazone is also a centrally-acting agent for painful musculoskeletal conditions. Data available from animal experiments as well as human study indicate that chlorzoxazone acts primarily at the level of the spinal cord and subcortical areas of the brain where it inhibits multisynaptic reflex a.c. involved in producing and maintaining skeletal muscle spasm of varied etiology. The clinical result is a reduction of the skeletal muscle spasm with relief of pain and increased mobility of the involved muscles.
• Toxicity: Oral, mouse: LD₅₀ = 440 mg/kg; Oral, rat: LD₅₀ = 763 mg/kg; Symptoms of overdose include diarrhea, dizziness, drowsiness, headache, light-headedness, nausea, and vomiting.
• Affected Organisms: Humans and other mammals
• Biotransformation: Chlorzoxazone is rapidly metabolized in the liver and is excreted in the urine, primarily in a conjugated form as the glucuronide.
• Protein Binding: 13-18%
• Elimination: Chlorzoxazone is rapidly metabolized and is excreted in the urine, primarily in a conjugated form as the glucuronide.
• References: Dong DL, Luan Y, Feng TM, Fan CL, Yue P, Sun ZJ, Gu RM, Yang BF: Chlorzoxazone inhibits contraction of rat thoracic aorta. Eur J Pharmacol. 2006 Sep 18;545(2-3):161-6. Epub 2006 Jun 29. [Pubmed] ; Park JY, Kim KA, Park PW, Ha JM: Effect of high-dose aspirin on CYP2E1 activity in healthy subjects measured using chlorzoxazone as a probe. J Clin Pharmacol. 2006 Jan;46(1):109-14. [Pubmed] ; Wan J, Ernstgard L, Song BJ, Shoaf SE: Chlorzoxazone metabolism is increased in fasted Sprague-Dawley rats. J Pharm Pharmacol. 2006 Jan;58(1):51-61. [Pubmed]
• External Links: Wikipedia; RxList; PDRhealth; Drugs.com

Sigma Aldrich - C4397

Biochem/physiol Actions
Chlorzoxazone is a skeletal muscle relaxant.

REFERENCES

• Dong DL, Luan Y, Feng TM, Fan CL, Yue P, Sun ZJ, Gu RM, Yang BF: Chlorzoxazone inhibits contraction of rat thoracic aorta. Eur J Pharmacol. 2006 Sep 18;545(2-3):161-6. Epub 2006 Jun 29. Pubmed
• Park JY, Kim KA, Park PW, Ha JM: Effect of high-dose aspirin on CYP2E1 activity in healthy subjects measured using chlorzoxazone as a probe. J Clin Pharmacol. 2006 Jan;46(1):109-14. Pubmed
• Wan J, Ernstgard L, Song BJ, Shoaf SE: Chlorzoxazone metabolism is increased in fasted Sprague-Dawley rats. J Pharm Pharmacol. 2006 Jan;58(1):51-61. Pubmed