Suffixes carboxamide

For acids that are named as alkanecarboxylic acids, the amides are named by using the suffix -carboxamide. Some amides, such as acetanilide, have historical names that are still commonly used. 

In an amide, a group such as —NH2, — NHR, or — NR2 is attached to an acyl group. Amides are named by replacing the suffix for the acid -ok acid) with the name -amide. The suffix -carboxamide indicates amides derived from cycloalkanecarboxyhc acids. 

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. 

For nomenclature purposes, substituents can be divided into those that are always cited as prefixes (e.g. chloro-, alkoxy-) and those which can be cited as either prefixes or suffixes e.g. oxo-/-one, carbamoyl-/-carboxamide). If any of the latter are present, the name will normally contain a suffix. However, only one kind of group can be cited as suffix, and this is chosen according to a strict order of priorities. The group thus selected is known as the principal characteristic group . 

The suffixes -oic acid, -al, -amide and -nitrile are used to name acyclic compounds having one or two characteristic groups. Locants are not necessary, as these groups must be at the end of a chain. The suffixes -carboxylic acid, -carbaldehyde, -carboxamide and -carbonitrile are used when more than two groups are attached to chains or one or more groups are attached to cycles. 

Amides are named by replacing the -oic acid or -ic acid suffix of the parent carboxylic acids with the suffix -amide, or hy replacing the -carboxylic acid ending with -carboxamide. Alkyl groups on nitrogen atoms are named as substituents, and are prefaced by N-or N,N-, followed by the name(s) of the alkyl group(s). 

Similar to the -carbonyl chloride suffix for acyl chlorides, -carboxamide is used when an amide group is attached to a ring. 

When an amide moiety is connected to a ring, the suffix carboxylic acid is replaced with carboxamide. ... 

In the case of multiple and cyclic carboxylic acids (and their derivatives) the acid group is treated as a unit corresponding to the suffix modes. .. carboxylic acid,... carboxamide,... carbonyl chloride, etc. 

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