Thymine Chinese alias: 5-methyluracil; 5-methyluracil; Thymosin
English name: Thymine
Abbreviation: T
English alias: 2,4 (1H, 3H) - Pyrimidine dione, 5-methyl -; 2,4-Dihydroxy-5-methylpyrimidine； 2,4-dioxy-5-methyl pyrimidine； 5-Methyluracil； Thy；5-methyl-uracil；5-methyl uracil；Thymine 2-4-Dihydroxy-5-methylpyrimidine；5-methylpyrimidine-2,4(1H,3H)-dione
Description: A kind of drug isolated from thymus pyrimidine Alkali. Soluble It can be decomposed in hot water at 335~337 ℃. ultraviolet rays Irradiation can make DNA molecule Two adjacent thymuses in the same chain Pyrimidine base Interformation Dimer , which affects the double helix structure of DNA and hinders its replication and transcription functions. Thymine (T) on one strand of DNA molecule and thymine (T) on the other strand adenine (A) Pair to form 2 hydrogen bond , Yes DNA double helix structure One of the important stabilizing forces. CAS No.: 65-71-4
EINECS No.: 200-616-1
Molecular formula: C five H six N two O two
Molecular weight: 126.1133
InChI： InChI=1/C five H six N two O two /c1-3-2-6-5(9)7-4(3)8/h2H,1H3,(H2,6,7,8,9)
Density: 1.226g/cm three
Melting point: 316-317 ℃
Boiling point: 403.8 ° C at 760 mmHg
Flash point: 198 ° C
Steam pressure: 4.25E -7 mmHg at 25°C
Safety terminology: S24/25 [1]
It is synthetic anti AIDS medicine AZT 、 DDT And key intermediates of related drugs. Upstream raw materials: Glacial acetic acid 、 Butyl acetate , methanol Methyl methacrylate , urea, hydrochloric acid, ethanol. It can also be synthesized by chemical methods. For drug manufacturing. Thymine is Deoxyribonucleic acid In Base one of. Thymine Deoxynucleoside , the hydrogen on the 5-position methyl is fluorine The substituted product is called trifluoro Thymidine , used as anti nucleic acid metabolism Antineoplastic drugs 。 [2] Thymidine nucleoside is a biochemical reagent used to prepare biological culture media, such as HAT selective medium Preparation of. Use of HAT selective medium Principle of thymidine : In the preparation of monoclonal antibody, HAT added Selective medium The basis is that there are two ways of DNA synthesis in cells: one is biosynthesis ("D way"), that is, nucleotides are synthesized from amino acids and other small molecular compounds to provide raw materials for the synthesis of DNA molecules. In this synthesis process, folic acid participates in this process as an important coenzyme, and HAT culture medium in Aminopterin It is an antagonist of folic acid and can block the "D way" of DNA synthesis. The other way is emergency way or remedy way ("S way"), which is to use Hypoxanthine - Guanine phosphonucleoside transferase (HGPRT) and Thymidine Kinase (TK) catalyzes hypoxanthine and thymine nucleoside to generate corresponding nucleotides. Both enzymes are indispensable. Therefore, in HAT culture medium, the "D way" of fusion of non fused effector B cells and two effector B cells is blocked by aminopterin. Although the "S way" is normal, it will generally die about 10 days due to lack of ability to proliferate in vitro culture medium. about Myeloma cells As for self fusion cells, because the commonly used myeloma cells are hypoxanthine guanine phosphorucleosidyltransferase deficient (HGPRT) cells, they do not have the "S way", and the "D way" is blocked by aminopterine, so they cannot proliferate in HAT culture medium and die quickly. Only myeloma cells and Effector B cell Formed by mutual fusion Hybridoma cell It not only has the "S way" of effector B cells, but also has the characteristics of long-term proliferation of myeloma cells in vitro culture medium, so it can selectively survive in HAT culture medium and continue to proliferate. Generally, in HAT, the concentration of H (hypoxanthine) is 1 × 10-4M, A (aminopterin) is 4 × 10-7M, and T (thymine) is 1.6 × 10-5M. In HT medium, only aminopterin is not added, and others are the same as HAT. Preparation of HAT medium ：100×A（ Aminopterin ）Storage solution: weigh 1.76mg of aminopterin and dissolve it in 90ml of ultrapure water, drop 1mol/L of NaOH 0.5ml as solubilizer, add 1mol/L of HCL 0.5ml for neutralization after complete dissolution, and then add ultrapure water to 100ml. 0.22um membrane filtration sterilization, small amount sub packaging, - 20 ℃ storage. [2] 
