Chemical names—continued

Table 12-2. Locants and Descriptors in Chemical Names—Continued...

The language used will be the Queen s English or that subset of it as approved by the Royal Society of Chemistry (RSC). Where chemical names are concerned there are some lost causes, such as caustic soda, where little would be gained if those who clean factories called this substance sodium hydroxide. Arguably, the name caustic soda conveys more useful information. Similar lost causes are spirits of wine (ethyl alcohol or ethanol) and spirits of salts (hydrochloric acid). While lipid chemists may insist on referring to triacylglycerols many people in industry continue to refer to triglycerides. Similarly trivial names for fatty acids such as lauric will continue to be used. The principle in all of this is to use the proper name but to mention other names that are in common use. 

The nomenclature of a science ought to be distinguished for its clearness and simplimty but it is by no means easy to seoure these conditions in a science like chemistry, where the rapid progress of discovery necessitates the continual addition of new and the frequent alteration of old namea The chemical name of a substance should not only identity and indi-vidualise that substance, but it should also express the composition and constitution of the body, if a compound, to which it is applied. The first of these conditions is readily attained but the second is much more difficult to secure, inasmuch as our ideas of the constitution of chemical compounds—the mode in which they are built up as it were— require firequent modification. On this account all attempts to frame a perfectly consistent system of chemical nomenclature have hitherto been only partially successful. 

The system of naming now used was devised by the International Union of Pure and Applied Chemistry, abbreviated IUPAC. In the IUPAC system, a chemical name has three parts prefix, parent, and suffix. The parent name tells how many carbon atoms are present in the longest continuous chain the suffix identifies what family the molecule belongs to and the prefix (if needed) specifies the location of various substituent groups attached to the parent chain ... 

Much is known about the biochemical toxicology of hepatotoxicants, yet much remains to be learned. Hepatotoxicity resulting in either cell necrosis, fibrosis, or fatty infiltration is known to be a widespread phenomenon, potentially of importance to human health. It is caused by numerous drugs and environmental agents, and its incidence is expected to increase as confounding viral liver disease becomes more prevalent. Much is known about mechanisms based upon comprehensive studies with a few prototypical chemicals—namely, CCb, ethanol and acetaminophen—which support a convergence of varied primary effects on the ultimate failure of mitochondrial function and Ca2+ homeostasis. The extensive metabolic activity of the liver exposes its cells to a continuous flux of prooxidants. The importance of metabolic activation for the production of reactive metabolites is well-... 

Table 2 Chemical names for the additives cited in this manuscript (Continued) ...

Nor is the confusion limited to botanical terms. The multitude of trivial chemical names in this field is again testimony to the conservatism of scientists. The classic example of how meaningless a term can become is perhaps that of the camphors, of which there must once have been at least 15— bergamot camphor, thyme camphor, cardamom camphor, and so on. Berzelius protested against this indiscriminate use in the 182O s Otto Wallach, 70 years later, persuaded his coworkers to drop the term. (It persists, however, in the trade.) The continued use of such words as limonene and citral, when more descriptive and comprehensible terms are at hand, is justified only because tradition is behind it. 

SYMBOLS AND TERMINOLOGY FOR PHYSICAL AND CHEMICAL QUANTITIES (continued) Name Symbol Definition SI unit... 

However, the physical-to-chemical paradox continues in an even more exciting fashion as follows. When, in light of the above discussion, electronegativity is recognized with the two-point limits shown in Figure 4.3(b), namely (Parr Yang, 1989 von Szentpaly, 2000)... 

Key parameter table Chemical names/suppliers continued... 

TABLE 15.1 (Continued) Official Chemical Name, E Numbers, Synonyms, and Chemical Formulas of Food-Grade Phosphoric Acid and Phosphates... 

Development of computer methods for the interconversion of chemical nomenclatures to and from molecular formulae, connection tables, and structural diagrams followed and seems to continue to follow two separate paths. On the one hand there are a great many reports, mainly from university sources, dealing with translation of systematic names into structural diagrams, and on the other hand there is relatively limited literature on translation of structural diagrams directly into systematic chemical names. Although these are two opposite directions of the same conversion, they have in practice very little in common as far as algorithms and applicable methods are concerned. 

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