Do you know what building this is now?

Today, after I had been at church I had to go to Cass Art to collect some materials I had ordered for an upcoming painting holiday in Provence. On the way I passed this building. When it was built it was in the west of the city, now it's in the centre.
One of the city's most impressive buildings it was built in 1778 by William Cunninghame, a prominent Glaswegian tobacco baron. Cunninghame headed one of three major syndicates that controlled the flow of tobacco into Scotland. He developed a string of outlets and representatives in the tobacco colonies, which bought tobacco from the planters and stored it until Cunninghame's ships arrived. Cunninghame's trading system was one of the most efficient and swift in the North Atlantic and it yielded enormous profits.

He invested some of these profits in his home, the Cunninghame Mansion, a townhouse which cost a staggering £10,000 to build and is thought to be one of the finest houses in Scotland. After his death it became part of the Royal Bank of Scotland, later an exchange for local merchants, then part of the telephone exchange. In 1996 it became ????. It stands today as a reminder of Glasgow's links to tobacco cultivated by enslaved people, and the profits tobacco yielded to the major Scottish merchants who dominated the trade.