Oxford Development Co. has ditched plans for a 121,000-square-foot office building at the SouthSide Works in favor of a proposed 170-unit apartment complex on the same land.

The city’s Urban Redevelopment Authority board is expected to vote Thursday on whether to rescind an approval given last year to sell a parcel of land on Sidney Street to Oxford and P.J. Dick for $2.5 million for the office project.

At the same time, members are expected to consider a separate resolution to enter into exclusive negotiations with Oxford, P.J. Dick and Lincoln Property Co. for construction of a 170-unit apartment building on the same tract of land.

In a report accompanying the proposed board actions, URA interim executive director Robert Rubinstein said Oxford has been unable to find a tenant for the office building. At one time, Oxford had hoped to have the project finished this year.

Steve Guy, Oxford president and CEO, said his company and the CBRE real estate firm spent 21 months between them marketing the property but came up empty.

Another company, dck Worldwide, had considered building a new headquarters at the site. When dck decided against doing so, Oxford agreed to participate in the development, teaming with P.J. Dick and Trammel Crow.

While Oxford struggled to find a tenant, the URA negotiated a $500,000 settlement with Nationwide Realty Investors over a long-standing restriction that prevented apartments from being built at SouthSide Works.

The settlement opened a new avenue for Oxford to explore, said Kyra Straussman, URA director of real estate. In conjunction with P.J. Dick and Lincoln, Oxford redirected its focus to apartments. The proposed 170-unit complex will feature a 200-space parking garage and street level retail.

“Looking at all the variables, it probably has the highest probability of success,” Mr. Guy said.

The complex, he added, will include a mix of units, with more than 50 percent being one-bedroom. Oxford has yet to establish rental rates or a total cost for the development.

It is planning to use one of the three parcels involved for the building, with an option on a second. The third parcel will remain public open space, Ms. Straussman said. The price for the land has yet to be established.

Mr. Guy said Oxford could break ground on the development this year.

The URA will keep a $50,000 deposit Oxford and P.J. Dick had made to buy the land for the office project.

In other action Thursday, the URA board will consider:

• A $1.8 million Pittsburgh Development Fund loan to Millcraft Industries for the $95 million Gardens at Market Square project on Forbes Avenue, Downtown. The loan will help complete funding for the office and hotel complex, which is expected to break ground in June.

• Entering into exclusive negotiations with Cozza Enterprises LLC for the purchase and redevelopment of the Sheraden Market and three other properties in Sheraden. Cozza plans to use the site for a Family Dollar Store and a Community Market Pavilion, which would feature an outdoor cafe and produce vendors. Development costs are estimated at $1.75 million.