H3As=O and its hydrocarbyl derivatives (analogously arsine imides and arsine sulfides), e.g.
(CH3)3As=O trimethylarsine oxide or trimethylarsane oxide.
See: imides
Source:
PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1319 (https://doi.org/10.1351/pac199567081307)