Compounds having the structure
R2C=NNHC(=O)C(=O)NH2, formally derived from the condensation of aldehydes or ketones with semioxamazide (the hydrazide of oxamic acid),
H2NNHC(=O)C(=O)NH2.
Source:
PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1365 (https://doi.org/10.1351/pac199567081307)