Prefix deoxy

The systematic name consists of the prefix deoxy- , preceded by the locant and followed by the stem name with such configurational prefixes as necessary to describe the configuration(s) at the asymmetric centres present in the deoxy compound. Configurational prefixes are cited in order commencing at the end farthest from C-l. Deoxy is regarded as a detachable prefix, i.e. it is placed in alphabetical order with any substituent prefixes. 

The name of an aldose derivative in which the aldehyde group has been replaced by a terminal CH3 group is derived from that of the appropriate alditol (see 2-Carb-19) by use of the prefix deoxy- . 

The compounds are named by use of a combination Df deoxy- and amino- prefixes. When the complete name of the derivative includes other prefixes, deoxy- takes its place in the alphabetical order of detachable prefixes. 

Alternatively they can be named on the basis of the corresponding fully saturated sugar by using the appropriate number of dehydro and deoxy prefixes (deoxy operations are regarded as formally preceding dehydro operations). The prefixes are placed in alphabetical order before the stem name. 

Nucleotides are named by adding a term denoting the number of phasphate groups (and their position) to the name of the nucleoside e.g. adenosine 5-monophosphate, AMP (or adenylate). In general, nucleotides are assumed to be ribonucleotides unless the prefix deoxy (or d- as abbreviation) is used. (See Figures 20.5 and 20.6)... 

For example, substitution can be made on an oxygen atom in the case of esters and ethers. It is characterised by the symbol O, which is placed after the locant. The compound prefix deoxy- is composed of the prefixes de-, meaning without in subtractive nomenclature, and oxy-, to indicate the subtraction of an oxy group from an -OH group C-O-H C-H. Such an operation is needed when an -OH group is replaced by another group, such as an amino group. 

With the exception of thymidine, these are the names of the ribonucleosides. Deoxyribonucleosides are indicated by the prefix deoxy in front of the nucleoside name thus deoxyadenosine contains deoxyribose instead of ribose. Thymidine indicates the deoxyribose derivative of thymine. Standard one-letter abbreviations are shown in parentheses. 

The names of the nucleosides formed from these bases and ribose are cytidine, thymidine, uridine, adenosine, and guanosine. Nucleosides formed from deoxyribose are named using the prefix deoxy-, as in deoxythymidine. 

All our descriptions of ribonucleosides, ribonucleotides, and ribonucleic acid also apply to the components of DNA. The principal difference between RNA and DNA is the presence of D-2-deoxyribose as the sugar in DNA instead of the D-ribose found in RNA. The prefix deoxy- means that an oxygen atom is missing, and the number 2 means it is missing from C2. 

DNA contains the bases adenine A), thymine (T), guanine (G), and cytosine (C). These bases are covalently attached to the deoxyribose phosphate to form nucleotides. The respective nucleotides are called dcoxyadenylic add (dA), deoxythy-midylic add (dT), deoxyguanylic acid (dC), and deoxycj tidylic acid (dC). The prefix "deoxy" indicates that the sugar is deoxyribose, rather than ribo e. The word "acid" indicates that the ribose con tains a covalently bound phosphoric acid group. 

In addition to the usual suffixes and prefixes just discussed, a few special prefixes are usually used for the semi-trivial names of the compounds. Thus the prefix dehydro- is used to indicate the loss of two hydrogen atoms from adjacent carbon atoms with the formation of a double bond (e.g, dehydroepiandrosterone). The prefix dihydro- or tetrahydro- indicates the addition of two or four hydrogen atoms to the molecule, respectively, as in dihydrocortisol and tetrahydrocortisol. The replacement of a hydroxyl group by hydrogen (COH CH) is denoted by the prefix deoxy- (or desoxy- [e.g., 11-deoxycorticosterone]). 

The names of nucleotides containing both deoxyribose and thymine do not have the prefix deoxy. Inosine-5 -monophosphate (IMP) is an intermediate in purine nucleotide synthesis. The base component of IMP is hypoxanthine. 

Nucleotides with the sugar ribose are ribonucleotides, and those having the sugar 2 -deox)uibose are deox)uibonucleotides. For a deox)uibonucleotide, the prefix deoxy- is placed before the modified nitrogenous base name. No prefix is required for ribonucleotides, or for th)unidine, which is found only in DNA. 

The prefix deoxy- is used to indicate deoxyribose as the sugar. No prefix means ribose. 

An alternative nomenclature system for nucleotides emphasizes their acidic properties (a result of the phosphate group). The name of the base unit from the above nomenclature system forms the basis of the name. The ending -osine monophosphate or -ine monophosphate is replaced by -ylic acid. The prefix deoxy- is used as before to distinguish deoxyribose from ribose. 

DNA is a macromolecule. Each word in its name is descriptive of its nature. Ribose is one form of sugar, along with glucose, fructose, sucrose, and others. The prefix deoxy- (the D in DNA) specifies a ribose that has lost one of its oxygen atoms at a specific site in the molecule. Nucleic acids (the N and the A in DNA) are a group of complex compounds comprised of carbohydrates, purines, pyrimidines, and phosphoric acid. Nucleic acids are found in all living cells. 

What is the meaning of the prefix deoxy- as it is used in carbohydrate chemistry ... 

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