DNA DNA Deoxyribonucleic acid (; DNA) is a molecule composed of two chains that coil around each other to form a double helix carrying the genetic instructions used in the growth, development, functioning and reproduction of all known living organisms and many viruses. DNA and ribonucleic acid (RNA) are nucleic acids; alongside proteins, lipids and complex carbohydrates (polysaccharides), nucleic acids are one of the four major types of macromolecules that are essential for all known forms of life. The two DNA strands are also known as polynucleotides as they are composed of simpler monomeric units called nucleotides. Each nucleotide is composed
Prephenic acid higher priority (according to CIP rules) on the two pseudoasymmetric carbons, "i.e." the carboxyl and the hydroxyl groups, in the "cis" configuration, or (1"s", 4"s") according to the new IUPAC stereochemistry rules (2013). The other stereoisomer, "i.e. trans" or, better, (1"r", 4"r"), is called epiprephenic. Prephenic acid Prephenic acid, commonly also known by its anionic form prephenate, is an intermediate in the biosynthesis of the aromatic amino acids phenylalanine and tyrosine, as well as of a large number of secondary metabolites of the shikimate pathway. It is biosynthesized by a [3,3]-sigmatropic Claisen rearrangement of chorismate. Prephenic acid is an example