hydromorphone

noun

hy·​dro·​mor·​phone -ˈmȯr-ˌfōn 

: a ketone C₁₇H₁₉NO₃ derived from morphine that is about five times as active biologically as morphine and is administered in the form of its hydrochloride C₁₇H₁₉NO₃·HCl as an analgesic

called also dihydromorphinone