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5-methyluridine
The chemical compound 5-methyluridine ( symbol m⁵U or m5U), also called ribothymidine, is a pyrimidine nucleoside. It is the ribonucleoside counterpart to the deoxyribonucleoside thymidine, which lacks a hydroxyl group at the 2' position. 5-Methyluridine contains a thymine base joined to a ribose pentose sugar. It is a white solid Solid is one of the four fundamental states of matter (the others being liquid, gas, and plasma). The molecules in a solid are closely packed together and contain the least amount of kinetic energy. A solid is characterized by structural .... See also * 5-Methylcytosine * 3-Methyluridine References {{DEFAULTSORT:Methyluridine5 Nucleosides Pyrimidinediones ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleoside
Nucleosides are glycosylamines that can be thought of as nucleotides without a phosphate group. A nucleoside consists simply of a nucleobase (also termed a nitrogenous base) and a five-carbon sugar (ribose or 2'-deoxyribose) whereas a nucleotide is composed of a nucleobase, a five-carbon sugar, and one or more phosphate groups. In a nucleoside, the anomeric carbon is linked through a glycosidic bond to the N9 of a purine or the N1 of a pyrimidine. Nucleotides are the molecular building-blocks of DNA and RNA. List of nucleosides and corresponding nucleobases The reason for 2 symbols, shorter and longer, is that the shorter ones are better for contexts where explicit disambiguation is superfluous (because context disambiguates) and the longer ones are for contexts where explicit disambiguation is judged to be needed or wise. For example, when discussing long nucleobase sequences in genomes, the CATG symbol system is much preferable to the Cyt-Ade-Thy-Gua symbol system (see '' N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleosides
Nucleosides are glycosylamines that can be thought of as nucleotides without a phosphate group. A nucleoside consists simply of a nucleobase (also termed a nitrogenous base) and a five-carbon sugar (ribose or 2'-deoxyribose) whereas a nucleotide is composed of a nucleobase, a five-carbon sugar, and one or more phosphate groups. In a nucleoside, the anomeric carbon is linked through a glycosidic bond to the N9 of a purine or the N1 of a pyrimidine. Nucleotides are the molecular building-blocks of DNA and RNA. List of nucleosides and corresponding nucleobases The reason for 2 symbols, shorter and longer, is that the shorter ones are better for contexts where explicit disambiguation is superfluous (because context disambiguates) and the longer ones are for contexts where explicit disambiguation is judged to be needed or wise. For example, when discussing long nucleobase sequences in genomes, the CATG symbol system is much preferable to the Cyt-Ade-Thy-Gua symbol system (see '' N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element is therefore not a compound. A compound can be transformed into a different substance by a chemical reaction, which may involve interactions with other substances. In this process, bonds between atoms may be broken and/or new bonds formed. There are four major types of compounds, distinguished by how the constituent atoms are bonded together. Molecular compounds are held together by covalent bonds; ionic compounds are held together by ionic bonds; intermetallic compounds are held together by metallic bonds; coordination complexes are held together by coordinate covalent bonds. Non-stoichiometric compounds form a disputed marginal case. A chemical formula specifies the number of atoms of each element in a compound molecule, using the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrimidine
Pyrimidine (; ) is an aromatic, heterocyclic, organic compound similar to pyridine (). One of the three diazines (six-membered heterocyclics with two nitrogen atoms in the ring), it has nitrogen atoms at positions 1 and 3 in the ring. The other diazines are pyrazine (nitrogen atoms at the 1 and 4 positions) and pyridazine (nitrogen atoms at the 1 and 2 positions). In nucleic acids, three types of nucleobases are pyrimidine derivatives: cytosine (C), thymine (T), and uracil (U). Occurrence and history The pyrimidine ring system has wide occurrence in nature as substituted and ring fused compounds and derivatives, including the nucleotides cytosine, thymine and uracil, thiamine (vitamin B1) and alloxan. It is also found in many synthetic compounds such as barbiturates and the HIV drug, zidovudine. Although pyrimidine derivatives such as alloxan were known in the early 19th century, a laboratory synthesis of a pyrimidine was not carried out until 1879, when Grimaux reported the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribonucleoside
A ribonucleoside is a type of nucleoside including ribose as a component. One example of a ribonucleoside is cytidine Cytidine (symbol C or Cyd) is a nucleoside molecule that is formed when cytosine is attached to a ribose ring (also known as a ribofuranose) via a β-N1- glycosidic bond. Cytidine is a component of RNA. It is a white water-soluble solid. which .... References {{Chem-stub * Ribosides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deoxyribonucleoside
A deoxyribonucleotide is a nucleotide that contains deoxyribose. They are the monomeric units of the informational biopolymer, deoxyribonucleic acid ( DNA). Each deoxyribonucleotide comprises three parts: a deoxyribose sugar (monosaccharide), a nitrogenous base, and one phosphoryl group. The nitrogenous bases are either purines or pyrimidines, heterocycles whose structures support the specific base-pairing interactions that allow nucleic acids to carry information. The base is always bonded to the 1'-carbon of the deoxyribose, an analog of ribose in which the hydroxyl group of the 2'-carbon is replaced with a hydrogen atom. The third component, the phosphoryl group, attaches to the deoxyribose monomer via the hydroxyl group on the 5'-carbon of the sugar. When deoxyribonucleotides polymerize to form DNA, the phosphate group from one nucleotide will bond to the 3' carbon on another nucleotide, forming a phosphodiester bond via dehydration synthesis. New nucleotides are always added ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thymidine
Thymidine (symbol dT or dThd), also known as deoxythymidine, deoxyribosylthymine, or thymine deoxyriboside, is a pyrimidine deoxynucleoside. Deoxythymidine 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 G1/early S phase. The prefix deoxy- is often left out since there are no precursors of thymine nucleotides involved in RNA synthesis. Before the boom in thymidine use caused by the need for thymidine in the production of the antiretroviral drug azidothymidine (AZT), much of the world's thymidine production came from herring sperm. Thymidine occurs almost exclusively in DNA but it also occurs in the T-loop of tRNA. Structure and properties In its composition, deoxythymidine is a nucleoside composed of deoxyribose (a pentose sugar) joined to the pyrimidine base thymine. Deoxythymidine can be phosphorylated with one, two or three phosphoric acid groups, creating dTMP (deoxythymidine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxyl
In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy groups. Both the negatively charged anion , called hydroxide, and the neutral radical , known as the hydroxyl radical, consist of an unbonded hydroxy group. According to IUPAC definitions, the term ''hydroxyl'' refers to the hydroxyl radical () only, while the functional group is called a ''hydroxy group''. Properties Water, alcohols, carboxylic acids, and many other hydroxy-containing compounds can be readily deprotonated due to a large difference between the electronegativity of oxygen (3.5) and that of hydrogen (2.1). Hydroxy-containing compounds engage in intermolecular hydrogen bonding increasing the electrostatic attraction between molecules and thus to higher boiling and melting points than found for compounds that lack this f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thymine
Thymine () ( symbol T or Thy) is one of the four nucleobases in the nucleic acid of DNA that are represented by the letters G–C–A–T. The others are adenine, guanine, and cytosine. Thymine is also known as 5-methyluracil, a pyrimidine nucleobase. In RNA, thymine is replaced by the nucleobase uracil. Thymine was first isolated in 1893 by Albrecht Kossel and Albert Neumann from calf thymus glands, hence its name. Derivation As its alternate name (5-methyluracil) suggests, thymine may be derived by methylation of uracil at the 5th carbon. In RNA, thymine is replaced with uracil in most cases. In DNA, thymine (T) binds to adenine (A) via two hydrogen bonds, thereby stabilizing the nucleic acid structures. Thymine combined with deoxyribose creates the nucleoside deoxythymidine, which is synonymous with the term thymidine. Thymidine can be phosphorylated with up to three phosphoric acid groups, producing dTMP (deoxythymidine monophosphate), dTDP, or dTTP (for the di- and tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribose
Ribose is a simple sugar and carbohydrate with molecular formula C5H10O5 and the linear-form composition H−(C=O)−(CHOH)4−H. The naturally-occurring form, , is a component of the ribonucleotides from which RNA is built, and so this compound is necessary for coding, decoding, regulation and expression of genes. It has a structural analog, deoxyribose, which is a similarly essential component of DNA. is an unnatural sugar that was first prepared by Emil Fischer and Oscar Piloty in 1891. It was not until 1909 that Phoebus Levene and Walter Jacobs recognised that was a natural product, the enantiomer of Fischer and Piloty's product, and an essential component of nucleic acids. Fischer chose the name "ribose" as it is a partial rearrangement of the name of another sugar, arabinose, of which ribose is an epimer at the 2' carbon; both names also relate to gum arabic, from which arabinose was first isolated and from which they prepared . Like most sugars, ribose exists ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sugar
Sugar is the generic name for sweet-tasting, soluble carbohydrates, many of which are used in food. Simple sugars, also called monosaccharides, include glucose, fructose, and galactose. Compound sugars, also called disaccharides or double sugars, are molecules made of two bonded monosaccharides; common examples are sucrose (glucose + fructose), lactose (glucose + galactose), and maltose (two molecules of glucose). White sugar is a refined form of sucrose. In the body, compound sugars are hydrolysed into simple sugars. Longer chains of monosaccharides (>2) are not regarded as sugars, and are called oligosaccharides or polysaccharides. Starch is a glucose polymer found in plants, the most abundant source of energy in human food. Some other chemical substances, such as glycerol and sugar alcohols, may have a sweet taste, but are not classified as sugar. Sugars are found in the tissues of most plants. Honey and fruits are abundant natural sources of simple sugars. Suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solid
Solid is one of the State of matter#Four fundamental states, four fundamental states of matter (the others being liquid, gas, and Plasma (physics), plasma). The molecules in a solid are closely packed together and contain the least amount of kinetic energy. A solid is characterized by structural rigidity and resistance to a force applied to the surface. Unlike a liquid, a solid object does not flow to take on the shape of its container, nor does it expand to fill the entire available volume like a gas. The atoms in a solid are bound to each other, either in a regular geometric lattice (crystal, crystalline solids, which include metals and ordinary ice), or irregularly (an amorphous solid such as common window glass). Solids cannot be compressed with little pressure whereas gases can be compressed with little pressure because the molecules in a gas are loosely packed. The branch of physics that deals with solids is called solid-state physics, and is the main branch of condens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
