iridoids

https://doi.org/10.1351/goldbook.I03253
Cyclic @M04026@ having the iridane skeleton (1-isopropyl-2,3-di-methylcyclopentane), the traditional, but not undisputed, numbering of which is shown in the diagram.
I03253.png
Source:
PAC, 1995, 67, 1307. (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1344 [Terms] [Paper]