Nomenclature parent name

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 ... 

Hansa Yellows, 1, 334 5, 299 Hantzsch synthesis, 2, 87-88 1,4-dihydropyridine, 2, 482 thiazoles, 6, 294-299 A -thiazolines, 6, 314 Hantzsch-Widman names parent names, 1, 35 stem suffixes, 1, 12 Hantzsch-Widman system nomenclature, 1, 11-12 Hardeners in photography... 

Paraxanthine—see Xanthine, 1,7-dimethyl-Parent name nomenclature, 1, 35 Parham cycloalkylation in chroman synthesis, 3, 783 Paromomycins as pharmaceuticals, 1, 154 Partial charge transfer from donor to acceptor stacks, 1, 350 Pasteurellosis... 

The two most commonly applied systems for naming polycyclic parents are in some ways complementary. Fusion nomenclature provides names for structures containing the maximum number of non-cumulative double bonds von Baeyer nomenclature (Section 1.02.3.4) names fully saturated structures. Thus names for partially hydrogenated structures can be arrived at either by adding hydro prefixes to fusion names or ene , diene , etc. suffixes to von Baeyer names (see examples 29 and 30). If needed, rules are available for... 

Substitution (see Seetion 1.02.9.1.1) is the formal proeedure most widely applied in modifying parent names. Indeed, the general term substitutive nomenclature is often used to describe the system of nomenclature in which substitution is the main operation. A fundamental concept of this system is that of the principal characteristic group . 

Part II consists entirely of systematic names of specific compounds according to Chemical Abstracts nomenclature (see the Index Guide in Chemical Abstracts, Volume 76, 1972). Each compound is listed under the parent name as it would appear in Chemical Abstracts, and each entry from Volumes 56 through 59 is followed by the registry number in brackets. Entries from Volumes 58 and 59 are, for the most part, taken from the appendices which follow the procedures. When the Chemical Abstracts name differs in Collective Indices 8 and 9, both names have been included. Some compounds in the appendices of this volume have been omitted from the index in accord with the guidelines given for Part I. 

In 1928, A. M. Patterson, later one of the authors of the Ring Index, wrote Any attempt to construct a strictly logical system of names for the large number of parent ring systems now known seems impractical, at least as far as common use is concerned. 7 This sentiment is no less applicable today. For heterocycles in particular, the number of trivial names in current use is large. In the 1969 IUPAC Rules,6 63 trivially named heterocyclic skeletons with various degrees of unsaturation are listed, with a further 25 in the 1973 Tentative Rules (Section D).8 Chemical Abstracts nomenclature rules list 83 such skeletons with maximum unsaturation, many of which are not included by IUPAC. Thus, although systematic operations are often required to derive the name of a heterocyclic skeleton, the parent names to which these operations are applied are frequently trivial. 

In using replacement nomenclature it is imperative to apply replacement prefixes only to a carbocyclic parent name, never to a heterocyclic... 

Although all alkaloids can be named by the principles already outlined in this article, the cumbersome nature of such names for complex ring systems makes it desirable to use trivial parent names for some large heterocyclic skeletons. It is preferable for such trivial names to refer to skeletons with no substituents (or very few), and it is often convenient for them to carry inherent stereochemical implications. The most extensive source of these names is the Chemical Abstracts Index Guide (or the Ninth Collective Index Nomenclature Manual), but the names given here do not correspond, in many cases, to those in common use, and IUPAC recommendations, when they appear, may well differ in some respects. Some of the principal skeletons listed by Chemical Abstracts are illustrated (122-130). 

Even in cases where a parent heterocyclic skeleton is not numbered as a whole (e.g., spiro method 6a, ii and ring assembly nomenclature) it is important to realize that substituent prefixes (including hydro) should appear before the whole parent name, not before the individual component names (see example 184). 

Hydrogenation products of complex aromatic ring systems that are not treated as alicyclic hydrocarbons are named by prefixing dihydro, tetrahydro, etc., to the parent name. The lowest locants are used. Perhydro" is used in trivial nomenclature to indicate a fully hydrogenated compound. 

In IUPAC nomenclature, benzene is designated as a parent name. Other compounds that contain the benzene molecule may be considered as substituted benzenes. In the case of monosubstitution (the replacement of a single hydrogen), the prefix of the substituent is added to the name benzene. 

The IUPAC rules for naming aldehydes append the suffix -al to the parent name. The aldehyde carbon is always the first carbon in the chain, so a locant is not necessary. The simplest aldehyde, methanal, is commonly known as formaldehyde, a highly toxic gas used to preserve biological specimens. Ethanal is the next aldehyde, although most organic chemists call it acetaldehyde. 2,2,2-Tri-chloroethanal, more commonly known as chloral, reacts with water to form the sedative chloral hydrate. Phenylmethanal, more commonly known as benzalde-hyde, is used as artificial cherry or almond flavoring. Nomenclature examples of aldehydes are shown in Figure 11.34. 

The IUPAC rules for naming ketones append the suffix -one to the parent name. The position of the ketone carbon is indicated by a locant number. Figure 11.37 gives three nomenclature examples of ketones. The simplest ketone, propanone, is commonly known as acetone. Acetone is an excellent solvent for most organic compounds and is the main ingredient in fingernail polish remover. Acetone is one of the ketone bodies that build up in the bloodstream from excessive metabolism of fats. Because ketones typically have a sweet taste and odor, this can give a patient with ketosis a characteristic acetone breath. ... 

Phane nomenclature Part 1 Phane parent names, Pure Appl. Chem. 70,1513— 1545 (1998) deutsche Ausgabe Karl-Heinz Hellwich Phannomenklatur Teil I Phanstammnamen, Angew. Chem. 118(23), 3967-3984 (2006)... 

When more than two substituents are present on the aromatic ring, the ortho, meta, para nomenclature is no longer valid and numbering has to be used (Fig.B). In such a case the relevant substituent has to be placed at position 1 if the parent name is toluene, aniline, etc. If the parent name is benzene, the numbering is done in such a way that the lowest possible numbers are used. In the example shown, any other numbering would result in the substituents having higher numbers(Fig.C). 

In replacement nomenclature, the name of a heterocyclic compound is formed by prefixing a terms, such as oxa , thia , aza , etc. to the name of the corresponding cyclic hydrocarbon. As IUPAC Rule B-4 states that the replacement method should be applied to a homocyclic hydrocarbon, we use pentalene for this purpose. The replacement procedure forbids the use of heterocyclic parent structures and for this reason the name thiathiophthene , which is found in the literature, is not in compliance with IUPAC recommendations. Another name which is sometimes found is thiothiophthene , which is even worse because of an incorrect use of the prefix thio . 

Nomenclature for the eight-membered 1,4-diheterocycles follows ILJPAG rules and the names are generated with the ACD software. The parent unsaturated systems are referred to as the corresponding -cines, whereas the fully saturated rings are recognized as -canes. Benzo and dibenzo derivatives follow the standard IUPAC nomenclature. Specific names appear for the individual compounds, where appropriate. 

The 2006 changes to CAS nomenclature have reduced the number of peptide parent names from about three thousand to fewer than one hundred of the most studied examples, e.g., bradykinin. All others are now named systematically. 

More recently, the parent name diazene -N=N- (has also been called diimide not recommended) was introduced, e.g., Ph-N=N-Ph = diphenyldiazene. The 2006 CAS nomenclature changes have included the following ... 

In lUPAC nomenclature, carboxylic acids are identified by a suffix added to the parent name of the longest chain, and two different endings are used depending on whether the carboxy group is bonded to a chain or ring. 

Table 19.1 lists common parent names for some simple carboxyhc acids. These parent names are used in the nomenclature of many other compounds with carbonyl groups (Chapters 21 and 22). 

The system of nomenclature for alkaloids of the tetrahydro series is somewhat confusing. Naturally occurring members of this series often occur in one of their optically active forms understandably, at the time of isolation, they were given trivial names of their own. The trivial names have survived despite the fact that the relationship of these alkaloids as tetrahydro derivatives of known quaternary alkaloids of the dibenzo Iquinolizine series (cf. berberine), which themselves have trivial names, has in most cases been clearly established. Although it would seem desirable to retain the names of the quaternary alkaloids of the series as parent names and to designate alkaloids of the tetrahydro series accordingly, this has its disadvantages in that the related quaternary bases of some alkaloids of the tetrahydro series are not known to occur in nature. 

For a number of inorganic acids, used as functional parents in organic nomenclature, the parent names used are now consistently allowed in the present recommendations, although fully systematic additive names are also given in all cases in Chapter IR-8. Examples are phosphinous acid, bromic acid and peroxydisulfuric acid. (Some of these names were absent from Ref. 11.)... 

In most cases, the compounds named substitutively in the present chapter may alternatively and equally systematically be named additively (Chapter IR-7), but it is important to note that for the parent hydrides presented here such additive names cannot be used as parent names in substitutive nomenclature. 

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