Beilouny Luxury Properties has lined up Tantrum, a new local clothing boutique, for its 757 Mass Ave building. The company also has been talking with several restaurants about taking an anchor restaurant/bar space on the corner, but has been unable to reach terms, including with Blu Martini, a sushi restaurant and cocktail bar on 96th Street, said Amy Peddycord, a project spokeswoman. Blu Martini is looking elsewhere downtown. Beilouny has sold 17 of 23 units in the 757 building, its flagship, including condos to race car drivers Michael Andretti and Dan Wheldon. The company also has a 17-unit condo project under construction around the corner, at 707 E. North St. Four of those units have been sold. That project does not include retail space.