Which class of drugs is represented by compounds that start with -lol from A to M?

The correct choice, represented by compounds that start with -lol from A to M, is beta-1 antagonists. This class of drugs primarily targets beta-1 adrenergic receptors, which are primarily located in the heart. By blocking these receptors, beta-1 antagonists decrease heart rate, reduce myocardial contractility, and lower blood pressure, making them effective in treating conditions such as hypertension, heart failure, and certain arrhythmias.

Beta-1 selectivity is important as it allows these medications to reduce cardiac workload without significantly affecting beta-2 receptors, which are found in the lungs and vascular smooth muscle. This selectivity minimizes the risk of side effects like bronchoconstriction, which can occur with non-selective beta antagonists.

While non-selective beta antagonists do exist and impact both beta-1 and beta-2 receptors, they typically include drugs that would start with -olol but span beyond M in their common naming convention, thus not fitting the criteria of this question. Alpha and beta antagonists also do not fit within the -lol suffix category, and inhibitors of dihydrofolate reductase represent a completely different mechanism of action unrelated to beta-adrenergic receptor antagonism. Thus, beta-1