An obsolete term, which should not be used, for imidic acids.
Any carboxylic acid having an imino substituent, HN=, replacing two hydrogens. A shortened form of imino carboxylic acid.
Obsolescent term for azaalkanoic acids and azacycloalkane-2-carboxylic acid, e.g. proline:
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Source: PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1343 (https://doi.org/10.1351/pac199567081307)