This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
[{'content': 'Which of the following is not a teiary amine derivative? \nSelect and explain. \nA. Atropine, B. Glycopyrrolate, C. Scopolamine, D. Hyoscine', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. b. Glycopyrrolate Glycopyrrolate is a synthetic quaternary anticholinergic drug, which doesn't cross the blood brain barrier and completely lacks central effects.", 'role': 'assistant'}]