Queen going around the compound (5)
I believe the answer is:
ether
'compound' is the definition.
(chemical compound)
'queen going around the' is the wordplay.
'queen' becomes 'ER' (abbreviation for Elizabeth Regina).
'going around' indicates putting letters inside.
'er' enclosing 'the' is 'ETHER'.
(Other definitions for ether that I've seen before include "Colourless volatile highly inflammable liquid" , "Colourless liquid used as a solvent" , "Volatile organic liquid once used as a general anaesthetic" , "Highly flammable liquid once used as an anaesthetic" , "Colourless, highly flammable liquid" .)