Search results
Results From The WOW.Com Content Network
L-Ribose Fischer Projection. Ribose is a simple sugar and carbohydrate with molecular formula C 5 H 10 O 5 and the linear-form composition H−(C=O)−(CHOH) 4 −H. The naturally occurring form, d-ribose, 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.
Both types of pentoses in DNA and RNA are in their β-furanose (closed five-membered ring) form and they define the identity of a nucleic acid. DNA is defined by containing 2'-deoxy-ribose nucleic acid while RNA is defined by containing ribose nucleic acid. [1] In some occasions, DNA and RNA may contain some minor bases.
In chemistry, a pentose is a monosaccharide (simple sugar) with five carbon atoms. [1] The chemical formula of many pentoses is C 5 H 10 O 5, and their molecular weight is 150.13 g/mol. [2] Pentoses are very important in biochemistry. Ribose is a constituent of RNA, and the related molecule, deoxyribose, is a constituent of DNA.
Synthesis of nucleosides involves the coupling of a nucleophilic, heterocyclic base with an electrophilic sugar. The silyl-Hilbert-Johnson (or Vorbrüggen) reaction, which employs silylated heterocyclic bases and electrophilic sugar derivatives in the presence of a Lewis acid, is the most common method for forming nucleosides in this manner.
Condensation of adenine and guanine forming a phosphodiester bond, the triphosphorylated ribose of the incoming nucleotide is attacked by the 3' hydroxyl of the polymer, releasing pyrophosphate. Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are the main examples of polynucleotides. They arise by condensation of nucleotides.
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.
Chemical structure of an LNA monomer an additional bridge bonds the 2' oxygen and the 4' carbon of the pentose. A locked nucleic acid (LNA), also known as bridged nucleic acid (BNA), [1] and often referred to as inaccessible RNA, is a modified RNA nucleotide in which the ribose moiety is modified with an extra bridge connecting the 2' oxygen and 4' carbon.
These three components are connected so that the nitrogenous base is attached to the first carbon of ribose (1’ carbon), and the phosphate group is attached to the 5’ carbon of ribose. While all nucleotides have this structure, the phosphate group makes a second connection to the ribose ring at the 3’ carbon in cyclic nucleotides.