I just remember this generally from studying, not specific drugs. And I’m not talking about a specific class either. I am actually going back to my pharm book to find an example for you.
Example – CCB – suffix = -dipine. Exceptions: Diltiazem and Verapamil
Example – alpha blockers – suffix = -zosin. Exceptions: Tamulosin and Silodosin.
You’re right, there are none that I know of in the beta blockers.