A 58-year-old man with chronic insomnia and mild obstructive sleep apnea (OSA) presents to the sleep clinic. He has been using alcohol as a sleep aid for the past 3 years, consuming 2–3 pegs of whisky nightly. He complains of daytime somnolence, poor sleep quality, and morning headaches. His wife reports loud snoring and witnessed apneic episodes. On examination, BMI is 28 kg/m², BP 138/88 mmHg, and oxygen saturation 94% on room air. Polysomnography confirms moderate OSA (AHI 25/hour). The patient is counseled to avoid alcohol and is being considered for pharmacotherapy. Which of the following sedative-hypnotics would be MOST APPROPRIATE for this patient?