Abstract
Selective ozonisation of isolumisterone produced 9β,10α‐bisnorchola‐4,6‐dien‐3‐on‐22‐al. This compound could be converted into: 6‐dehydro‐9β,10α‐progesterone (9β,10α‐pregna‐4,6‐diene‐3,20‐dione); 6‐dehydro‐17α‐hydroxy‐9β,10α‐progesterone (9β,10α‐pregna‐4,6‐dien‐17α‐ol‐3,20‐dione) and 6‐dehydro‐9β,10α‐testosterone (9β,10α‐androsta‐4,6‐dien‐17β‐ol‐3‐one).