Structure
Ribose is an aldopentose (a monosaccharide containing five carbon atoms) that, in its open chain form, has an aldehyde functional group at one end. In the conventional numbering scheme for monosaccharides, the carbon atoms are numbered from C1' (in the aldehyde group) to C5'. The deoxyribose derivative found in DNA differs from ribose by having a hydrogen atom in place of the hydroxyl group at C2'.
Like many monosaccharides, ribose exists in an equilibrium among 5 forms--the linear form H−(C=O)−(CHOH)4–H and either of the two ring forms: alpha- or beta-ribofuranose ("C3'-endo"), with a five-membered ring, and alpha- or beta-ribopyranose ("C2'-endo"), with a six-membered ring. The beta-ribopyranose form predominates in aqueous solution.
The "-" in the name -ribose refers to the stereochemistry of the chiral carbon atom farthest away from the aldehyde group (C4'). In -ribose, as in all -sugars, this carbon atom has the same configuration as in -glyceraldehyde.
Read more about this topic: Ribose
Famous quotes containing the word structure:
“The structure was designed by an old sea captain who believed that the world would end in a flood. He built a home in the traditional shape of the Ark, inverted, with the roof forming the hull of the proposed vessel. The builder expected that the deluge would cause the house to topple and then reverse itself, floating away on its roof until it should land on some new Ararat.”
—For the State of New Jersey, U.S. public relief program (1935-1943)
“I’m a Sunday School teacher, and I’ve always known that the structure of law is founded on the Christian ethic that you shall love the Lord your God and your neighbor as yourself—a very high and perfect standard. We all know the fallibility of man, and the contentions in society, as described by Reinhold Niebuhr and many others, don’t permit us to achieve perfection.”
—Jimmy Carter (James Earl Carter, Jr.)
“Who says that fictions only and false hair
Become a verse? Is there in truth no beauty?
Is all good structure in a winding stair?
May no lines pass, except they do their duty
Not to a true, but painted chair?”
—George Herbert (1593–1633)