A Boston-based developer has acquired 441 Stuart St. in Boston’s Back Bay and plans to convert the 11-story office/retail building to condominiums. Gold Assoc. paid $37.5 million for the asset, said company official Ronald Gold. The firm has begun discussions with city officials to convert the upper floors of the building to luxury condominiums, he said.

“That’s what we do,” Gold said in explaining the residential conversion plan, adding that the dour office market would make it difficult to pursue office deals in the 177,000-square-foot building, which opened in 1927. The first floor of 441 Stuart St. will remain retail, said Gold, while a long-term lease to fitness center Healthworks for the second and third floors will remain in place, as well. “They have a great presence,” Gold said of Healthworks, suggesting the club could help attract interest in the residential units.

Gold Assoc., whose principals also include Neal S. Gold, has retained Boston architect Bargmann Hendrie & Archtype to design the residential piece of the property. An exact number of units has not been determined, said Ronald Gold, although he estimated it will be between 90 and 114 condominium spaces. Owned previously on a long-term basis by 441 Stuart Street Realty Trust, which is controlled by Boston parking magnate W. Kevin Fitzgerald, the building is just one of several Class B office buildings in the city being eyed for conversion to condominiums, with nearby 330 Stuart St. also being marketed with that concept in mind