Complex sentence: Dezocine is unusual among opioids as it is the only primary amine known to be an active opioid, but it is a mixed agonist-antagonist as with other drugs in this class, Young AM, Stephens KR, Hein DW, Woods JH.
Split into simpler sentences: Dezocine is unusual among opioids as it is the only primary amine known to be an active opioid. It is a mixed agonist-antagonist as with other drugs in this class, Young AM, Stephens KR, Hein DW, Woods JH.