tropones

https://doi.org/10.1351/goldbook.T06520
Compounds that contain the cyclohepta-2,4,6-trienone ring system.
T06520.png
Source:
PAC, 1995, 67, 1307. (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1373 [Terms] [Paper]