Naming, acid anhydrides alkyl groups

Carboxylic acids are named by adding the suffix oic acid to the base name. Acid chlorides are name by changing the ic acid of the parent carboxylic acid to yl chloride. The suffix acid is changed to anhydride to name acid anhydrides. Esters are named like acid salts by changing ic acid to ate and preceding the name by the name of the alkyl group. To name amides, the oic acid is changed to amide. 

Oxazolones are simply cyclic anhydrides of A-acyl-a-amino acids, and are constructed in the way that this implies. If the nitrogen also carries an alkyl group, cyclisation can only lead to an overall neutral product by its adopting a zwitterionic structure, for which no neutral canonical form can be written - a mesoionic structure. Mesoionic oxazolones (named munchnones by Huisgen after their discovery at the University of Munchen, Germany) undergo ready dipolar cycloadditions, with loss of carbon dioxide from initial adduct the examples show the conversion of a miinchnone into a mesoionic thiazolone and into an imidazole. 

Carboxylic acid derivatives are named as acyl halides, carboxylic anhydrides, alkyl alkanoates, alkanamides, and alkanenitriles, depending on the functional group. 

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