rotenoids

https://doi.org/10.1351/goldbook.R05417
Naturally occurring substances containing a cis-fused tetrahydrochromeno[3,4-b]chromene @N04256@. Many rotenoids contain an additional ring, e.g rotenone:
R05417.png
Source:
PAC, 1995, 67, 1307. (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1364 [Terms] [Paper]