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药品详细

Thioguanine(硫鸟嘌呤)

化学结构式图
中文名
硫鸟嘌呤
英文名
Thioguanine
分子式
C5H5N5S
化学名
2-amino-6,7-dihydro-3H-purine-6-thione
分子量
Average: 167.192
Monoisotopic: 167.026565875
CAS号
154-42-7
ATC分类
L01B 抗代谢药
药物类型
small molecule
阶段
approved
商品名
Lanvis;Tabloid;Wellcome U3B;
同义名
2-Amino 6MP;2-Amino-6-mercaptopurine;2-Amino-6-merkaptopurin;2-Amino-6-purinethiol;2-Aminopurin-6-thiol;2-Aminopurine-6-thiol;2-Aminopurine-6(1H)-thione;6-Mercapto-2-aminopurine;6-Mercaptoguanine;6-Thioguanine;TG;ThG;Tioguanin;Tioguanine;
基本介绍

An antineoplastic compound which also has antimetabolite action. The drug is used in the therapy of acute leukemia. [PubChem]

生产厂家
  • Glaxosmithkline
封装厂家
参考
Synthesis Reference Not Available
General Reference Not Available
剂型
规格
化合物类型
Type small molecule
Classes
  • Purines and Purine Derivatives
Substructures
  • Aliphatic and Aryl Amines
  • Pyrimidines and Derivatives
  • Imidazoles
  • Heterocyclic compounds
  • Aromatic compounds
  • Purines and Purine Derivatives
  • Cyanamides
适应症
Cancer 癌症;
药理
Indication For remission induction and remission consolidation treatment of acute nonlymphocytic leukemias.
Pharmacodynamics Thioguanine is an antineoplastic anti-metabolite used in the treatment of several forms of leukemia including acute nonlymphocytic leukemia. Anti-metabolites masquerade as purine or pyrimidine - which become the building blocks of DNA. They prevent these substances becoming incorporated in to DNA during the "S" phase (of the cell cycle), stopping normal development and division. Thioguanine was first synthesized and entered into clinical trial more than 30 years ago. It is a 6-thiopurine analogue of the naturally occurring purine bases hypoxanthine and guanine. Intracellular activation results in incorporation into DNA as a false purine base. An additional cytotoxic effect is related to its incorporation into RNA. Thioguanine is cross-resistant with mercaptopurine. Cytotoxicity is cell cycle phase-specific (S-phase).
Mechanism of action Thioguanine competes with hypoxanthine and guanine for the enzyme hypoxanthine-guanine phosphoribosyltransferase (HGPRTase) and is itself converted to 6-thioguanilyic acid (TGMP), which reaches high intracellular concentrations at therapeutic doses. TGMP interferes with the synthesis of guanine nucleotides by its inhibition of purine biosynthesis by pseudofeedback inhibition of glutamine-5-phosphoribosylpyrophosphate amidotransferase, the first enzyme unique to the de novo pathway of purine ribonucleotide synthesis. TGMP also inhibits the conversion of inosinic acid (IMP) to xanthylic acid (XMP) by competition for the enzyme IMP dehydrogenase. Thioguanine nucleotides are incorporated into both the DNA and the RNA by phosphodiester linkages, and some studies have shown that incorporation of such false bases contributes to the cytotoxicity of thioguanine. Its tumor inhibitory properties may be due to one or more of its effects on feedback inhibition of de novo purine synthesis; inhibition of purine nucleotide interconversions; or incorporation into the DNA and RNA. The overall result of its action is a sequential blockade of the utilization and synthesis of the purine nucleotides.
Absorption Absorption of an oral dose is incomplete and variable, averaging approximately 30% of the administered dose (range: 14% to 46%)
Volume of distribution Not Available
Protein binding Not Available
Metabolism
Hepatic. First converted to 6-thioguanilyic acid (TGMP). TGMP is further converted to the di- and tri-phosphates, thioguanosine diphosphate (TGDP) and thioguanosine triphosphate (TGTP) by the same enzymes that metabolize guanine nucleotides.
Route of elimination Not Available
Half life 80 minutes (range 25-240 minutes)
Clearance Not Available
Toxicity Oral, mouse: LD50 = 160 mg/kg. Symptoms of overdose include nausea, vomiting, malaise, hypotension, and diaphoresis.
Affected organisms
  • Humans and other mammals
Pathways
Pathway Name SMPDB ID
Smp00430 Thioguanine Pathway SMP00430
理化性质
Properties
State solid
Experimental Properties
Property Value Source
melting point >360 °C PhysProp
water solubility 36.3 mg/mL Not Available
logP -0.07 HANSCH,C ET AL. (1995)
Predicted Properties
Property Value Source
water solubility 8.34e-01 g/l ALOGPS
logP -0.36 ALOGPS
logP -0.35 ChemAxon
logS -2.3 ALOGPS
pKa (strongest acidic) 10.53 ChemAxon
pKa (strongest basic) 3.7 ChemAxon
physiological charge 0 ChemAxon
hydrogen acceptor count 4 ChemAxon
hydrogen donor count 3 ChemAxon
polar surface area 79.09 ChemAxon
rotatable bond count 0 ChemAxon
refractivity 46.89 ChemAxon
polarizability 15.65 ChemAxon
药物相互作用
Drug Interaction
Aminosalicylic Acid Aminosalicylic acid may increase the toxicity of thiopurine, thioguanine.
Busulfan Busulfan increases the hepatoxicity of Thioguanine during long-term concomitant therapy.
Mercaptopurine Complete cross resistance may occur.
Mesalazine Mesalazine may increase the toxicity of thiopurine, thioguanine.
Natalizumab The immunosuppressant, Thioguanine, may increase the adverse effects of Natalizumab. Increased risk of Progressive Multifocal Leukoencephalopathy (PML) and other infections. Concurrent therapy should be avoided.
Olsalazine Olsalazine may increase the toxicity of thiopurine, thioguanine.
Sulfasalazine Sulfasalazine may increase the toxicity of thiopurine, thioguanine.
Trastuzumab Trastuzumab may increase the risk of neutropenia and anemia. Monitor closely for signs and symptoms of adverse events.
食物相互作用
Not Available

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