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ChemSpider 2D Image | Isoniazid | C6H7N3O


  • Molecular FormulaC6H7N3O
  • Average mass137.139 Da
  • Monoisotopic mass137.058914 Da
  • ChemSpider ID3635

More details:

Featured data source

Validated by Experts, Validated by Users, Non-Validated, Removed by Users

200-214-6 [EINECS]
4-Pyridinecarboxylic acid hydrazide
4-Pyridinecarboxylic acid, hydrazide [ACD/Index Name]
54-85-3 [RN]
Idrazide dell'acido isonicotinico [Italian]
Isoniazida [Spanish] [INN]

Validated by Experts, Validated by Users, Non-Validated, Removed by Users

4188 [DBID]
MFCD00006426 [DBID]
AI3-23936 [DBID]
AIDS007657 [DBID]
AIDS-007657 [DBID]
AIDS032280 [DBID]
AIDS-032280 [DBID]
AIDS088821 [DBID]
AIDS-088821 [DBID]
  • Experimental Physico-chemical Properties
  • Predicted Physico-chemical Properties
  • Miscellaneous
    • Appearance:

      white crystalline powder OU Chemical Safety Data (No longer updated) More details
      WHITE POWDER NIH Clinical Collection [SMR000059082]
      White Solid Novochemy [NC-44486]
    • Stability:

      Stable, but may be air or light sensitive. Combustible. Incompatible with strong oxidizing agents,chloral, aldehydes, iodine, ferric salts, hypochlorites. OU Chemical Safety Data (No longer updated) More details
    • Toxicity:

      Organic Compound; Amine; Hydrazine; Amide; Ester; Drug; Food Toxin; Metabolite; Fatty Acid Synthesis Inhibitor; Synthetic Compound; Antitubercular Agent Toxin, Toxin-Target Database T3D4777
      ORL-DOG LD50 50 mg kg-1, IVN-MUS LD50 149 mg kg-1, SCU-RAT LD50 329 mg kg-1, ORL-GPG LD50 255 mg kg-1 OU Chemical Safety Data (No longer updated) More details
    • Safety:

      20/21/22 Novochemy [NC-44486]
      20/21/36/37/39 Novochemy [NC-44486]
      22-36/37/38 Alfa Aesar A10583
      22-36/37/38-40 Alfa Aesar A10583
      26-36/37 Alfa Aesar A10583
      26-36/37-60 Alfa Aesar A10583
      GHS07; GHS09 Novochemy [NC-44486]
      H301 H315 H319 H335 H351 LKT Labs [I7341]
      H302-H315-H319-H335 Alfa Aesar A10583
      H332; H403 Novochemy [NC-44486]
      Harmful/Irritant/Air Sensitive/Moisture Sensitive/Store under Argon SynQuest 4H56-1-VD
      Irritant SynQuest 4H56-1-VD, 69243
      J04AC01 Wikidata Q423169
      P102; P210; P262; P270; P302+P352; P308+P313 Novochemy [NC-44486]
      P261-P280-P305+P351+P338-P304+P340-P405-P501a Alfa Aesar A10583
      Safety glasses, gloves, good ventilation. OU Chemical Safety Data (No longer updated) More details
      Warning Alfa Aesar A10583
      Warning Novochemy [NC-44486]
      WARNING: Irritates skin and eyes, harmful if swallowed Alfa Aesar A10583
      Xn Abblis Chemicals AB1009474
      Xn Novochemy [NC-44486]
    • Target Organs:

      Reductase inhibitor; Catalase-peroxidase TargetMol T0972
    • Chemical Class:

      A carbohydrazide obtained by formal condensation between pyridine-4-carboxylic acid and hydrazine. ChEBI CHEBI:6030
    • Compound Source:

      synthetic Microsource [01500355]
    • Bio Activity:

      Antibacterial MedChem Express HY-B0329
      Anti-infection MedChem Express HY-B0329
      Anti-infection; MedChem Express HY-B0329
      Enzyme TargetMol T0972
      Isoniazid is an antibacterial agent used primarily as a tuberculostatic. MedChem Express
      Isoniazid is an antibacterial agent used primarily as a tuberculostatic.; Target: Antibacterial; Isoniazid is a prodrug and must be activated by a bacterial catalase-peroxidase enzyme that in M. MedChem Express HY-B0329
      Isoniazid is an antibacterial agent used primarily as a tuberculostatic.;Target: Antibacterial;Isoniazid is a prodrug and must be activated by a bacterial catalase-peroxidase enzyme that in M. tuberculosis is called KatG [1]. KatG couples the isonicotinic acyl with NADH to form isonicotinic acyl-NADH complex. This complex binds tightly to the enoyl-acyl carrier protein reductase known as InhA, thereby blocking the natural enoyl-AcpM substrate and the action of fatty acid synthase. This process inhibits the synthesis of mycolic acid, required for the mycobacterial cell wall. A range of radicals are produced by KatG activation of isoniazid, including nitric oxide, which has also been shown to be important in the action of another antimycobacterial prodrug PA-824 [2, 3]. Isoniazid is bactericidal to rapidly dividing mycobacteria, but is bacteriostatic if the mycobacteria are slow-growing [4]. MedChem Express HY-B0329
      NAPDH;Catalase-peroxidase TargetMol T0972
  • Gas Chromatography

Predicted data is generated using the ACD/Labs Percepta Platform - PhysChem Module

Density: 1.2±0.1 g/cm3
Boiling Point:
Vapour Pressure:
Enthalpy of Vaporization:
Flash Point:
Index of Refraction: 1.584
Molar Refractivity: 36.9±0.3 cm3
#H bond acceptors: 4
#H bond donors: 3
#Freely Rotating Bonds: 1
#Rule of 5 Violations: 0
ACD/LogP: -0.89
ACD/LogD (pH 5.5): -0.64
ACD/BCF (pH 5.5): 1.00
ACD/KOC (pH 5.5): 10.66
ACD/LogD (pH 7.4): -0.63
ACD/BCF (pH 7.4): 1.00
ACD/KOC (pH 7.4): 10.76
Polar Surface Area: 68 Å2
Polarizability: 14.6±0.5 10-24cm3
Surface Tension: 57.8±3.0 dyne/cm
Molar Volume: 110.2±3.0 cm3

Predicted data is generated using the US Environmental Protection Agency’s EPISuite™

 Log Octanol-Water Partition Coef (SRC):
    Log Kow (KOWWIN v1.67 estimate) =  -0.81
    Log Kow (Exper. database match) =  -0.70
       Exper. Ref:  Hansch,C et al. (1995)

 Boiling Pt, Melting Pt, Vapor Pressure Estimations (MPBPWIN v1.42):
    Boiling Pt (deg C):  329.79  (Adapted Stein & Brown method)
    Melting Pt (deg C):  118.95  (Mean or Weighted MP)
    VP(mm Hg,25 deg C):  1.21E-005  (Modified Grain method)
    MP  (exp database):  171.4 deg C
    Subcooled liquid VP: 0.000396 mm Hg (25 deg C, Mod-Grain method)

 Water Solubility Estimate from Log Kow (WSKOW v1.41):
    Water Solubility at 25 deg C (mg/L):  1.669e+004
       log Kow used: -0.70 (expkow database)
       no-melting pt equation used
     Water Sol (Exper. database match) =  1.4e+005 mg/L (25 deg C)
        Exper. Ref:  MERCK INDEX (1996)

 Water Sol Estimate from Fragments:
    Wat Sol (v1.01 est) =  1e+006 mg/L
    Wat Sol (Exper. database match) =  140000.00
       Exper. Ref:  MERCK INDEX (1996)

 ECOSAR Class Program (ECOSAR v0.99h):
    Class(es) found:

 Henrys Law Constant (25 deg C) [HENRYWIN v3.10]:
   Bond Method :   1.21E-014  atm-m3/mole
   Group Method:   Incomplete
 Henrys LC [VP/WSol estimate using EPI values]:  1.308E-010 atm-m3/mole

 Log Octanol-Air Partition Coefficient (25 deg C) [KOAWIN v1.10]:
  Log Kow used:  -0.70  (exp database)
  Log Kaw used:  -12.306  (HenryWin est)
      Log Koa (KOAWIN v1.10 estimate):  11.606
      Log Koa (experimental database):  None

 Probability of Rapid Biodegradation (BIOWIN v4.10):
   Biowin1 (Linear Model)         :   0.5277
   Biowin2 (Non-Linear Model)     :   0.3597
 Expert Survey Biodegradation Results:
   Biowin3 (Ultimate Survey Model):   2.6819  (weeks-months)
   Biowin4 (Primary Survey Model) :   3.6311  (days-weeks  )
 MITI Biodegradation Probability:
   Biowin5 (MITI Linear Model)    :  -0.0695
   Biowin6 (MITI Non-Linear Model):   0.0000
 Anaerobic Biodegradation Probability:
   Biowin7 (Anaerobic Linear Model):  1.0954
 Ready Biodegradability Prediction:   NO

Hydrocarbon Biodegradation (BioHCwin v1.01):
    Structure incompatible with current estimation method!

 Sorption to aerosols (25 Dec C)[AEROWIN v1.00]:
  Vapor pressure (liquid/subcooled):  0.0528 Pa (0.000396 mm Hg)
  Log Koa (Koawin est  ): 11.606
   Kp (particle/gas partition coef. (m3/ug)):
       Mackay model           :  5.68E-005 
       Octanol/air (Koa) model:  0.0991 
   Fraction sorbed to airborne particulates (phi):
       Junge-Pankow model     :  0.00205 
       Mackay model           :  0.00452 
       Octanol/air (Koa) model:  0.888 

 Atmospheric Oxidation (25 deg C) [AopWin v1.92]:
   Hydroxyl Radicals Reaction:
      OVERALL OH Rate Constant =   5.8373 E-12 cm3/molecule-sec
      Half-Life =     1.832 Days (12-hr day; 1.5E6 OH/cm3)
      Half-Life =    21.988 Hrs
   Ozone Reaction:
      No Ozone Reaction Estimation
   Fraction sorbed to airborne particulates (phi): 0.00329 (Junge,Mackay)
    Note: the sorbed fraction may be resistant to atmospheric oxidation

 Soil Adsorption Coefficient (PCKOCWIN v1.66):
      Koc    :  99.63
      Log Koc:  1.998 

 Aqueous Base/Acid-Catalyzed Hydrolysis (25 deg C) [HYDROWIN v1.67]:
    Rate constants can NOT be estimated for this structure!

 Bioaccumulation Estimates from Log Kow (BCFWIN v2.17):
   Log BCF from regression-based method = 0.500 (BCF = 3.162)
       log Kow used: -0.70 (expkow database)

 Volatilization from Water:
    Henry LC:  1.21E-014 atm-m3/mole  (estimated by Bond SAR Method)
    Half-Life from Model River: 5.666E+010  hours   (2.361E+009 days)
    Half-Life from Model Lake : 6.182E+011  hours   (2.576E+010 days)

 Removal In Wastewater Treatment:
    Total removal:               1.85  percent
    Total biodegradation:        0.09  percent
    Total sludge adsorption:     1.76  percent
    Total to Air:                0.00  percent
      (using 10000 hr Bio P,A,S)

 Level III Fugacity Model:
           Mass Amount    Half-Life    Emissions
            (percent)        (hr)       (kg/hr)
   Air       1.71e-007       44           1000       
   Water     46.3            900          1000       
   Soil      53.6            1.8e+003     1000       
   Sediment  0.0891          8.1e+003     0          
     Persistence Time: 974 hr


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