Thymidine (also known as deoxythymidine; other names deoxyribosylthymine, thymine deoxyriboside) is a pyrimidine deoxynucleoside used as a cell synchronizing agent. The nucleoside T in double-stranded DNA is deoxythymidine, and it pairs with deoxyadenosine (A). It synchronizes the cells in the G1/early S phase, which is useful in cell biology.

Physicochemical Properties

Molecular Formula	C10H14N2O5
Molecular Weight	242.2286
Exact Mass	242.09
Elemental Analysis	C, 49.58; H, 5.83; N, 11.56; O, 33.02
CAS #	50-89-5
Related CAS #	33430-62-5 (Thymidine-5-monophosphate disodium salt)
PubChem CID	5789
Appearance	White to off-white solid powder
Density	1.6±0.1 g/cm3
Boiling Point	510.1±60.0 °C at 760 mmHg
Melting Point	187-189ºC
Flash Point	262.3±32.9 °C
Vapour Pressure	0.0±3.0 mmHg at 25°C
Index of Refraction	1.674
LogP	-0.9
Hydrogen Bond Donor Count	3
Hydrogen Bond Acceptor Count	5
Rotatable Bond Count	2
Heavy Atom Count	17
Complexity	381
Defined Atom Stereocenter Count	3
SMILES	O1[C@]([H])(C([H])([H])O[H])[C@]([H])(C([H])([H])[C@]1([H])N1C(N([H])C(C(C([H])([H])[H])=C1[H])=O)=O)O[H]
InChi Key	IQFYYKKMVGJFEH-XLPZGREQSA-N
InChi Code	InChI=1S/C10H14N2O5/c1-5-3-12(10(16)11-9(5)15)8-2-6(14)7(4-13)17-8/h3,6-8,13-14H,2,4H2,1H3,(H,11,15,16)/t6-,7+,8+/m0/s1
Chemical Name	1-[(2R,4S,5R)-4-hydroxy-5-(hydroxymethyl)oxolan-2-yl]-5-methylpyrimidine-2,4-dione
Synonyms	DThyd; Deoxyribothymidine; Deoxythymidine; NSC 21548; NSC-21548; NSC21548; Thymidin; deoxythymidine; 2'-Deoxythymidine; 5-Methyldeoxyuridine; Thymidin; Beta-Thymidine; DThyd; AI3-52267; AI3 52267; AI352267
HS Tariff Code	2934.99.03.00
Storage	Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month
Shipping Condition	Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Biological Activity

Targets	Microbial Metabolite; DNA Synthesis; Human Endogenous Metabolite
ln Vitro	Thymidine (NSC 21548), a pyrimidine nucleoside that pairs with adenine during DNA synthesis. It is made up of the pyrimidine base thymine attached to the sugar deoxyribose.[1]
ln Vivo	The loss of CD4+Vβ8+ and CD8+Vβ8+ T cells induced by thymidine and Tomudex is totally restored by thymidine (500 mg/kg; i.p.; twice daily) [3].
Cell Assay	72 hours following the infection of shRNA lentiviruses, 4 mM thymidine is applied to MDA-MB-231 cells for 18 hours. At 0, 6, and 18 hours, release and harvest cells. Use FACS analysis to ascertain the cell cycle distribution.
Animal Protocol	Animal/Disease Models: 8-12 weeks balb/c (Bagg ALBino) mouse [3] Doses: 500 mg/kg Route of Administration: intraperitoneal (ip) injection; twice (two times) daily Experimental Results: After injection of SEB, methotrexate and Tomudex-induced Vβ8+ T were completely eliminated Cell loss.
Toxicity/Toxicokinetics	Mouse(ip): LD50 2512 mg/kg Toxicity Data Mouse(ip): LD50 2512 mg/kg
References	[1]. Cell Synchronization by Double Thymidine Block. Bio Protoc. 2018 Sep 5;8(17). [2]. Autoradiographic visualization of synthesis of deoxyribonucleic acid in tissue culture with tritium-labelled thymidine. Nature. 1958 Jan 24;181(4604):274-5. [3]. Inhibition of thymidine synthesis by folate analogues induces a Fas-Fas ligand-independentdeletion of superantigen-reactive peripheral T cells. Int Immunol. 2001 Jan;13(1):85-93.
Additional Infomation	Thymidine is a pyrimidine 2'-deoxyribonucleoside having thymine as the nucleobase. It has a role as a metabolite, a human metabolite, an Escherichia coli metabolite and a mouse metabolite. It is functionally related to a thymine. It is an enantiomer of a telbivudine. Thymidine is a pyrimidine deoxynucleoside. Thymidine is the DNA nucleoside T, which pairs with deoxyadenosine (A) in double-stranded DNA. In cell biology it is used to synchronize the cells in S phase. Thymidine is a metabolite found in or produced by Escherichia coli (strain K12, MG1655). Thymidine has been reported in Streptomyces piomogenus, Peucedanum japonicum, and other organisms with data available. Thymidine is a pyrimidine nucleoside that is composed of the pyrimidine base thymine attached to the sugar deoxyribose. As a constituent of DNA, thymidine pairs with adenine in the DNA double helix. (NCI04) Thymidine is a metabolite found in or produced by Saccharomyces cerevisiae. A nucleoside in which THYMINE is linked to DEOXYRIBOSE.

Solubility Data

Solubility (In Vitro)	DMSO: 48~50 mg/mL (198.2~206.4 mM) H2O: ~33.3 mg/mL (~137.6 mM)
Solubility (In Vivo)	Solubility in Formulation 1: 20 mg/mL (82.57 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution; with sonication (<60°C).  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	4.1283 mL	20.6415 mL	41.2831 mL
	5 mM	0.8257 mL	4.1283 mL	8.2566 mL
	10 mM	0.4128 mL	2.0642 mL	4.1283 mL

*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.