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Details

Stereochemistry ACHIRAL
Molecular Formula C9H7N7O2S
Molecular Weight 277.263
Optical Activity NONE
Defined Stereocenters 0 / 0
E/Z Centers 0
Charge 0

SHOW SMILES / InChI
Structure of AZATHIOPRINE

SMILES

CN1C=NC(=C1SC2=NC=NC3=C2N=CN3)[N+]([O-])=O

InChI

InChIKey=LMEKQMALGUDUQG-UHFFFAOYSA-N
InChI=1S/C9H7N7O2S/c1-15-4-14-7(16(17)18)9(15)19-8-5-6(11-2-10-5)12-3-13-8/h2-4H,1H3,(H,10,11,12,13)

HIDE SMILES / InChI

Molecular Formula C9H7N7O2S
Molecular Weight 277.263
Charge 0
Count
MOL RATIO 1 MOL RATIO (average)
Stereochemistry ACHIRAL
Additional Stereochemistry No
Defined Stereocenters 0 / 0
E/Z Centers 0
Optical Activity NONE

Description

Azathioprine remains one of the most important and widely prescribed drugs for immunosuppression/immunomodulation in autoimmune disease over 30 years after its introduction. Azathioprine is licensed for the treatment of only a limited range of autoimmune disorders, which is probably a reflection on the age of the drug. Widening the license for a drug is both costly and time consuming, and it would make no commercial sense for manufacturers to do so, at this late stage of life, for azathioprine. However, azathioprine is now so well established as an immunomodulating drug in autoimmune disorders that it represents the gold standard by which other drugs are compared. Azathioprine is indicated as an adjunct for the prevention of rejection in renal homotransplantation. It is also indicated for the management of active rheumatoid arthritis to reduce signs and symptoms. The combined use of azathioprine tablets with disease modifying anti-rheumatic drugs (DMARDs) has not been studied for either added benefit or unexpected adverse effects. The use of azathioprine tablets with these agents cannot be recommended. Azathioprine is a pro-drug, converted in the body to the active metabolite 6-mercaptopurine. Azathioprine acts to inhibit purine synthesis necessary for the proliferation of cells, especially leukocytes and lymphocytes. It is a safe and effective drug used alone in certain autoimmune diseases, or in combination with other immunosuppressants in organ transplantation. Its most severe side effect is bone marrow suppression, and it should not be given in conjunction with purine analogues such as allopurinol. The enzyme thiopurine S-methyltransferase (TPMT) deactivates 6-mercaptopurine. Genetic polymorphisms of TPMT can lead to excessive drug toxicity, thus assay of serum TPMT may be useful to prevent this complication. Azathioprine is metabolized to 6-mercaptopurine (6-MP). Both compounds are rapidly eliminated from blood and are oxidized or methylated in erythrocytes and liver; no azathioprine or mercaptopurine is detectable in urine after 8 hours. Activation of 6-mercaptopurine occurs via hypoxanthine-guanine phosphoribosyltransferase (HGPRT) and a series of multi-enzymatic processes involving kinases to form 6-thioguanine nucleotides (6-TGNs) as major metabolites.

CNS Activity

Approval Year

Targets

Primary TargetPharmacologyConditionPotency

Conditions

ConditionModalityTargetsHighest PhaseProduct
Palliative
IMURAN

Cmax

ValueDoseCo-administeredAnalytePopulation
16.9 ng/mL
50 mg single, oral
MERCAPTOPURINE ANHYDROUS plasma
Homo sapiens
64.8 ng/mL
100 mg single, oral
MERCAPTOPURINE ANHYDROUS plasma
Homo sapiens

AUC

ValueDoseCo-administeredAnalytePopulation
41.6 ng × h/mL
50 mg single, oral
MERCAPTOPURINE ANHYDROUS plasma
Homo sapiens
116 ng × h/mL
50 mg single, intravenous
MERCAPTOPURINE ANHYDROUS plasma
Homo sapiens
137.7 ng × h/mL
100 mg single, oral
MERCAPTOPURINE ANHYDROUS plasma
Homo sapiens

T1/2

ValueDoseCo-administeredAnalytePopulation
1.1 h
50 mg single, intravenous
MERCAPTOPURINE ANHYDROUS plasma
Homo sapiens
5 h
single, oral
AZATHIOPRINE serum
Homo sapiens

Funbound

ValueDoseCo-administeredAnalytePopulation
70%
single, oral
AZATHIOPRINE serum
Homo sapiens

Doses

AEs

PubMed

Sample Use Guides

In Vivo Use Guide
Rheumatoid Arthritis: is given on a daily basis. The initial dose should be approximately 1.0 mg/kg (50 to 100 mg) given as a single dose or on a twice-daily schedule. The dose may be increased, beginning at 6 to 8 weeks and thereafter by steps at 4-week intervals, if there are no serious toxicities and if initial response is unsatisfactory. Dose increments should be 0.5 mg/kg daily, up to a maximum dose of 2.5 mg/kg per day. Therapeutic response occurs after several weeks of treatment, usually 6 to 8 an adequate trial should be a minimum of 12 weeks.
Route of Administration: Oral
In Vitro Use Guide
Unknown
Substance Class Chemical
Record UNII
MRK240IY2L
Record Status Validated (UNII)
Record Version