Derivatives of carboxylie acids in which the OH portion of the COOH group has been replaced by NH2 (as such or substituted) are called amides or, more accurately, carboxamides. Such compounds have the generic structures RCONH2, RCONHR’, and RCONR’R”, as well as RCONHCOR,” and RCON(COR’)COR”. The latter two classes may be referred to as secondary amides and tertiary amides, respectively. Compounds containing the group —CONHCO— or —CON(R)CO— as part of a ring are called imides or, more accurately, carboximides.
Broadly speaking, the class terms amide and imide also denote the corresponding nitrogen derivatives of noncarboxylic acids such as those discussed in Chapters 18, 36, and 40—e.g., sulfonamides and amides of phosphorus acids, as well as ionic derivatives of ammonia such as sodium amide (NaNH2).
Sulfur analogs of carboxamides and dicarboximides, called thioamides and thioimides, are included in this chapter.
Naming of peptides, a special subclass made up of amides derived