Arnold & Porter added four partners and one counsel to its Chicago office.Eric S. Prezant joins the bankruptcy and restructuring group as a partner. He represents corporate, banking, real estate and financial clients in corporate and real estate acquisitions and dispositions, brownfield redevelopment projects, mergers and acquisitions, and corporate restructuring and workouts.Donal M. O’Brien joins the corporate and finance group as a partner. He represents clients in mergers and acquisitions and corporate …