Name, systematic

Chemical nomenclature has a very large number of specific procedures to create chemical names, and many of these are not easily amenable to algorithmic representation, requiring significant investments in both development and validation time to develop automated procedures. Software developers of N2S engines prefer to support just the basic operations for conversion, at least at the early stages of development. 

FIGURE 3.6 Twelve structures that may correspond to the abbreviation DPA. The letters used in the abbreviation are bold and capitalized. 

The conversion of systematic names to their chemical structures is a time-consuming, skill-intensive process, and is not a minor undertaking. Such a project is guaranteed to take many years of development to cover the most important nomenclature operations. 

Chemical Information Mining Facilitating Literature-Based Discovery 

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For simple compounds the main reference uses the systematic I.U.P.A.C. nomenclature, but other nomenclature is cross-referenced to the systematic name. 

Enzymes are classified in terms of the reactions which they catalyse and were formerly named by adding the suffix ase to the substrate or to the process of the reaction. In order to clarify the confusing nomenclature a system has been developed by the International Union of Biochemistry and the International Union of Pure and Applied Chemistry (see Enzyme Nomenclature , Elsevier, 1973). The enzymes are classified into divisions based on the type of reaction catalysed and the particular substrate. The suffix ase is retained and recommended trivial names and systematic names for classification are usually given when quoting a particular enzyme. Any one particular enzyme has a specific code number based upon the new classification. 

Hydrolases. Enzymes catalysing the hydrolytic cleavage ofC —O, C —N and C —C bonds. The systematic name always includes hydrolase but the recommended name is often formed by the addition of ase to the substrate. Examples are esterases, glucosidases, peptidases, proteinases, phospholipases. Other bonds may be cleaved besides those cited, e.g. during the action of sulphatases and phosphatases. 

Red lead is insoluble in water. Like lead(II) oxide it can readily be reduced to lead. The structure of the solid, as the systematic name suggests, consists of two interpenetrating oxide structures, in which each Pb atom is surrounded octahedrally by six oxygen atoms, and each Pb" by three (pyramidal) oxygen atoms, the oxygen atoms being shared between these two units of structure. With dilute nitric acid the lead(ll) part dissolves, and the lead(IV) part precipitates as lead(IV) oxide ... 

In 1814, J.J. Berzelius succeeded for the first time in systematically naming chemical substances by building on the results of quantitative analyses and on the definition of the term "element by Lavoisier. In the 19th century, the number of known chemical compounds increased so rapidly that it became essential to classify them, to avoid a complete chaos of trivial names (see Section 2.2.4). 

Sucrose is dextro-rotatory. Fructose shows a laevo-rotation greater in magnitude than the dextro-rotation shown by glucose. Hence as the hydrolysis of sucrose proceeds, the dextro-rotation gradually falls to zero and the solution finally shows a laevo-rotation. This hydrolysis is therefore sometimes called inversion and so the enzyme which catalyses the reaction is known as " invertase. Its more systematic name is, however, sucrase. 

The systematic name for the conjugate acid of water (HjO" ) is oxonium ion Its com mon name is hydronium ion... 

Branched alkyl groups are named by using the longest continuous chain that begins at the point of attachment as the base name Thus the systematic names of the two C3H7 alkyl groups are propyl and 1 methylethyl Both are better known by their common names n propyl and isopropyl respectively... 

By combining the basic principles of lUPAC notation with the names of the various alkyl groups we can develop systematic names for highly branched alkanes We 11 start with the following alkane name it then increase its complexity by successively adding methyl groups at various positions... 

A single alkane may have several different names a name may be a common name or it may be a systematic name developed by a well defined set of rules The most widely used system is lUPAC nomencla ture Table 2 6 summarizes the rules for alkanes and cycloalkanes Table 2 7 gives the rules for naming alkyl groups... 

Dibal IS an informal name given to the organometallic compound [(CH3)2CHCH2l2AlH used as a reducing agent m certain reactions Can you figure out the systematic name from which dibal IS denved" ... 

It IS hard to find a class of compounds in which the common names of its members have influenced organic nomenclature more than carboxylic acids Not only are the common names of carboxylic acids themselves abundant and widely used but the names of many other compounds are derived from them Benzene took its name from benzoic acid and propane from propionic acid not the other way around The name butane comes from butyric acid present m rancid butter The common names of most aldehydes are derived from the common names of carboxylic acids—valeraldehyde from valeric acid for exam pie Many carboxylic acids are better known by common names than by their systematic ones and the framers of the lUPAC rules have taken a liberal view toward accepting these common names as permissible alternatives to the systematic ones Table 19 1 lists both common and systematic names for a number of important carboxylic acids... 

Systematic names for carboxylic acids are derived by counting the number of car bons m the longest continuous chain that includes the carboxyl group and replacing the e ending of the corresponding alkane by oic acid The first three acids m Table 19 1 methanoic (1 carbon) ethanoic (2 carbons) and octadecanoic acid (18 carbons) illus trate this point When substituents are present their locations are identified by number... 

The systematic name for bi carbonate ion is hydrogen carbonate Thus the system atic name for sodium bicar bonate (NaHCOs) is sodium hydrogen carbonate... 

Many carboxylic acids are much better known by their common names than by their sys tematic names Some of these follow Provide a stmctural formula for each one on the basis of its systematic name... 

Many naturally occurring nitrogen compounds and many nitrogen containing drugs are bet ter known by common names than by their systematic names A few of these follow Wnte a struc tural formula for each one... 

Phenol IS both an important industrial chemical and the parent of a large class of compounds widely distributed as natural products Although ben zenol IS the systematic name for CgHsOH the lUPAC rules permit phe nol to be used instead Substituted derivatives are named on the basis of phenol as the parent compound... 

The lUPAC mles permit the use of common names for a number of familiar phenols and aryl ethers These common names are listed here along with their systematic names Write the stmcture of each compound... 

Spermaceti is a wax obtained from the sperm whale It contains among other materials an ester known as cetyl palmitate which is used as an emollient in a number of soaps and cosmetics The systematic name for cetyl palmi tate IS hexadecyl hexadecanoate Write a structural formula for this substance... 

Nebulanne is a toxic nucleoside isolated from a species of mushroom Its systematic name IS 9 P D nbofuranosylpurine Write a structural formula for nebulanne... 

Radicals having three or more free valences are named by adding the suffixes -triyl, -tetrayl, etc. to the systematic name of the corresponding hydrocarbon. 

Systematic names formed by applying the principles of substitutive nomenclature are single words except for compounds named as acids. First one selects the parent compound, and thus the suffix, from the characteristic group listed earliest in Table 1.7. All remaining functional groups are handled as prefixes that precede, in alphabetical order, the parent name. Two examples may be helpful ... 

Amides. For primary amides the suffix -amide is added to the systematic name of the parent acid. For example, CH3—CO—NHj is acetamide. Oxamide is retained for HjN—CO—CO—NHj. The name -carboxylic acid is replaced by -carboxamide. 

Systematic name Trivial name Systematic name Trivial name... 

Systematic names should be used in derivatives formed by substitution on a carbon atom. Note The names in parentheses are abandoned but are listed for reference to older literature. 

These contracted names of heterocyclic nitrogen compounds are retained as alternatives for systematic names, sometimes with indicated hydrogen. In addition, names of 0x0 derivatives of fully saturated nitrogen heterocycles that systematically end in -idinone are often contracted to end in -idone when no ambiguity might result. For example. 

AUotropes. Systematic names for gaseous and liquid modifications of elements are sometimes needed. Allotropic modifications of an element bear the name of the atom together with the descriptor to specify the modification. The following are a few common examples ... 

For most molecules with more than three atoms the name of the molecule is given in parentheses after the chemical formula. In most cases, only the common and not the systematic name is given so that, for example, C2H4 is called ethylene and not ethene. 

Fig. 1. Polyhydric alcohols. Systematic names are (1) 2,2-bis(hydroxymeth5l)-l,3-propanediol (2)...

Indole is a heteroaromatic compound consisting of a fused benzene and pyrrole ring, specifically ben2o[ ]pyrrole. The systematic name, IJT-indole (1) distinguishes it from the less stable tautomer 3JT-indole [271-26-1] (2). Iff-Indole [120-72-9] is also more stable than the isomeric ben2o[ ] pyrrole, which is called isoindole, (2H, (3) and IH (4)). A third isomer ben2o[i ]pyrrole is a stable compound called indoli2idine [274-40-8] (5). 

Systematic name (trivial or CAS Mol Freezi Boilin Refta Specift Viscosity Surface Heat Liquid Flash In Water... 

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