Metharbital (CHEM002200)

Record Information
Version1.0
Creation Date2009-07-21 20:26:57 UTC
Update Date2026-05-14 16:39:34 UTC
Accession NumberCHEM002200
Identification
Common NameMetharbital
ClassSmall Molecule
Description
Metharbital is only found in individuals that have used or taken this drug. It was patented in 1905 by Emil Fischer working for Merck. It was marketed as Gemonil by Abbott Laboratories. It is a barbiturate anticonvulsant, used in the treatment of epilepsy. It has similar properties to phenobarbital. Metharbital binds at a distinct binding site associated with a Cl- ionopore at the GABAA receptor, increasing the duration of time for which the Cl- ionopore is open. The post-synaptic inhibitory effect of GABA in the thalamus is, therefore, prolonged. All of these effects are associated with marked decreases in GABA-sensitive neuronal calcium conductance (gCa). The net result of barbiturate action is acute potentiation of inhibitory GABAergic tone. Barbiturates also act through potent (if less well characterized) and direct inhibition of excitatory AMPA-type glutamate receptors, resulting in a profound suppression of glutamatergic neurotransmission.
Contaminant Sources
  • HMDB Contaminants - Urine
  • T3DB toxins
  • ToxCast & Tox21 Chemicals
Contaminant Type
  • Amide
  • Amine
  • Anticonvulsant
  • Drug
  • Metabolite
  • Organic Compound
  • Synthetic Compound
Chemical Structure
MOLSDFPDBSMILESInChI
Synonyms
ValueSource
GemonilKegg
MetharbitoneHMDB
EndiemalHMDB
MethobarbitoneHMDB
Chemical FormulaC9H14N2O3
Average Molecular Mass198.219 g/mol
Monoisotopic Mass198.100 g/mol
CAS Registry Number50-11-3
IUPAC Name5,5-diethyl-1-methyl-1,3-diazinane-2,4,6-trione
Traditional Namemetharbital
SMILESCCC1(CC)C(=O)NC(=O)N(C)C1=O
InChI IdentifierInChI=1S/C9H14N2O3/c1-4-9(5-2)6(12)10-8(14)11(3)7(9)13/h4-5H2,1-3H3,(H,10,12,14)
InChI KeyFWJKNZONDWOGMI-UHFFFAOYSA-N
Chemical Taxonomy
Description Belongs to the class of organic compounds known as barbituric acid derivatives. Barbituric acid derivatives are compounds containing a perhydropyrimidine ring substituted at C-2, -4 and -6 by oxo groups.
KingdomOrganic compounds
Super ClassOrganoheterocyclic compounds
ClassDiazines
Sub ClassPyrimidines and pyrimidine derivatives
Direct ParentBarbituric acid derivatives
Alternative Parents
Substituents
  • Barbiturate
  • N-acyl urea
  • Ureide
  • 1,3-diazinane
  • Dicarboximide
  • Urea
  • Carbonic acid derivative
  • Carboxylic acid derivative
  • Azacycle
  • Organic nitrogen compound
  • Organonitrogen compound
  • Organooxygen compound
  • Hydrocarbon derivative
  • Organic oxide
  • Organopnictogen compound
  • Organic oxygen compound
  • Carbonyl group
  • Aliphatic heteromonocyclic compound
Molecular FrameworkAliphatic heteromonocyclic compounds
External DescriptorsNot Available
Biological Properties
StatusDetected and Not Quantified
OriginExogenous
Cellular Locations
  • Cytoplasm
  • Extracellular
  • Membrane
Biofluid LocationsNot Available
Tissue LocationsNot Available
PathwaysNot Available
ApplicationsNot Available
Biological RolesNot Available
Chemical RolesNot Available
Physical Properties
StateSolid
AppearanceWhite powder.
Experimental Properties
PropertyValue
Melting Point150.5°C
Boiling PointNot Available
Solubility1980 mg/L (at 25°C)
Predicted Properties
PropertyValueSource
Water Solubility19.5 g/LALOGPS
logP1.18ALOGPS
logP0.94ChemAxon
logS-1ALOGPS
pKa (Strongest Acidic)8.75ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area66.48 ŲChemAxon
Rotatable Bond Count2ChemAxon
Refractivity49.15 m³·mol⁻¹ChemAxon
Polarizability19.6 ųChemAxon
Number of Rings1ChemAxon
BioavailabilityYesChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Spectra
Spectra
Toxicity Profile
Route of ExposureNot Available
Mechanism of ToxicityMetharbital binds at a distinct binding site associated with a Cl- ionopore at the GABAA receptor, increasing the duration of time for which the Cl- ionopore is open. The post-synaptic inhibitory effect of GABA in the thalamus is, therefore, prolonged. All of these effects are associated with marked decreases in GABA-sensitive neuronal calcium conductance (gCa). The net result of barbiturate action is acute potentiation of inhibitory GABAergic tone. Barbiturates also act through potent (if less well characterized) and direct inhibition of excitatory AMPA-type glutamate receptors, resulting in a profound suppression of glutamatergic neurotransmission.
MetabolismNot Available
Toxicity ValuesNot Available
Lethal DoseNot Available
Carcinogenicity (IARC Classification)No indication of carcinogenicity to humans (not listed by IARC).
Uses/SourcesMetharbital is used for the treatment of epilepsy.
Minimum Risk LevelNot Available
Health EffectsMay cause a potentially dangerous rash that may develop into Stevens Johnson syndrome, an extremely rare but potentially fatal skin disease.
SymptomsSigns of overdose include confusion (severe), decrease in or loss of reflexes, drowsiness (severe), fever, irritability (continuing), low body temperature, poor judgment, shortness of breath or slow or troubled breathing, slow heartbeat, slurred speech, staggering, trouble in sleeping, unusual movements of the eyes, weakness (severe).
TreatmentNot Available
Concentrations
Not Available
External Links
DrugBank IDDB00463
HMDB IDHMDB0014606
FooDB IDNot Available
Phenol Explorer IDNot Available
KNApSAcK IDNot Available
BiGG IDNot Available
BioCyc IDNot Available
METLIN IDNot Available
PDB IDNot Available
Wikipedia LinkMetharbital
Chemspider ID3957
ChEBI ID102408
PubChem Compound ID4099
Kegg Compound IDNot Available
YMDB IDNot Available
ECMDB IDNot Available
References
Synthesis ReferenceNot Available
MSDSNot Available
General References