With an estrane or gonane skeleton, including 18-substituted derivatives and derivatives where

Official title: {with an estrane or gonane skeleton, including 18-substituted derivatives and derivatives where position 17-beta is substituted by a carbon atom not directly bonded to another carbon atom and not being part of an amide group}

C07J41/0044 (With an estrane or gonane skeleton, including 18-substituted derivatives and derivatives where) appears on 46 US grants and 51 published applications in this corpus.