Isopropyl ent-15α-bromo-16-oxo-beyeran-19-oate.

The title compound, C(23)H(35)BrO(3), synthesized by esterification and bromination of isosteviol, comprises a fused four-ring system. Two of the six-membered rings adopt a regular chair conformation, whereas the remaining six-membered ring is an unsymmetrical distorted chair. The stereochemistry at the two six-membered ring junctions is trans, while the five-membered ring adopts an envelope conformation.