the steroid anaesthetic althesin ( glaxo ) , which is a mixture of two c21 steroids , alphaxalone ( 3 alpha-hydroxy-5 alpha-pregnane-11 , 20-dione -- the active compound ) and alphadolone acetate ( 21-acetoxy-3 alpha-hydroxy-5 alpha-pregnane-11 , 20-dione ) , has been especially useful for the study of forebrain-autonomic and neuroendocrine functions .
C0038317
steroid
C0033006
pregnane