Timidin

Timidin is not a widely recognized chemical name in standard databases. It may be a misspelling, a regional or historical variant of thymidine, or a term encountered in fiction or specialized texts. Because there is no established profile for a compound officially named timidin, most reliable information typically points to thymidine or related nucleosides when the term appears.

Thymidine, also called deoxythymidine, is a nucleoside composed of thymine—a pyrimidine base—linked to deoxyribose sugar. Its chemical formula is C10H14N2O5 and its molecular weight is about 242.23 g/mol. Thymidine is one of the four nucleosides in DNA; it is not used in RNA, where uracil substitutes for thymine. In cells, thymidine is phosphorylated to dTMP (thymidine monophosphate) by thymidylate kinase, and subsequently to dTDP and dTTP, which are essential building blocks for DNA synthesis and repair.

Biologically, thymidine can be produced through salvage pathways, recycling thymine and deoxyribose phosphate, or via de novo pathways that generate the nucleotide pool required for DNA replication. The synthesis of dTMP from dUMP by thymidylate synthase is a key regulatory step and a target of certain chemotherapy agents, such as antifolates and fluoropyrimidines, which disrupt DNA synthesis in rapidly dividing cells.

In laboratory contexts, thymidine and its phosphorylated forms are used as substrates in DNA synthesis and sequencing protocols. Thymidine analogs are employed as antiviral or anticancer drugs, whereas thymidine itself is primarily a biological substrate rather than a therapeutic agent. See also thymidine.