One of the principles set out in ISO 257 Pesticides and other agrochemicals – Principles for the selection of common names is that common names for simple esters and salts should be assigned to the parent acid, alcohol or base when the biological activity derives from the parent.
The identity of the simple anion, cation, or radical is then indicated by adding a modifier to the common name. For esters and salts of acids, and for salts of alcohols, the modifier is a hyphenated suffix. For esters of alcohols, and for salts of bases, the modifier is a separate word. For example:
Multiplicative affixes are used when they are necessary to avoid ambiguity.
For simple anions, cations and radicals, traditional names are used as modifiers for common names. They are also used for some less simple substances, when more systematic names would include locants and the traditional names are unambiguous. For example:
|Traditional name||Systematic name||Example|
|isopropyl||1-methylethyl (= propan-2-yl)||benthiavalicarb-isopropyl|
The chemical names of some relatively simple substances can be more complicated than is desirable in a common name, and so recommended names were developed or adopted for some of the more frequently occurring ions and radicals and published in ISO 257:2004 (edition 3). These names, and others added in ISO 257:2018 (edition 4), are listed in the following table and should be used as modifiers for common names in place of the chemical names.
|Recommended name||Systematic name||Example|
|ethadyl||1,2-ethanediyl (= ethylene)||TCA-ethadyl|
|isoctyl||“iso-octyl” (mixed C-8 alkyl radical)||MCPA-isoctyl|
|meptyl||1-methylheptyl (= octan-2-yl)||fluroxypyr-meptyl|
|metilsulfate†||methyl sulfate||difenzoquat metilsulfate|
|mexyl||1-methylhexyl (= heptan-2-yl)||cloquintocet-mexyl|
† Adopted WHO INN modifier
* Introduced in 2018 in 4th edition of ISO 257.
There is a separate index of simple salts and esters, and they are also listed in the Notes field of the data sheets of their parent compounds. Their IUPAC systematic names, CAS systematic names, CAS Registry Numbers, molecular formulae and InChIKeys are included in the indexes.