Not only is it right next to the station but it's one of the busiest streets in the country. Cars and busses go up and down it 24hrs a day.
In terms of safety you'll be fine. Glasgow isn't really unsafe. Just don't go looking for trouble. I used to go through it everyday for years and I'm in it at least 3 times a week (at 1am) these days and never once had any bother.