Hoag Hospital has acquired the iconic Ziggurat building in Laguna Niguel for $207 million, the U.S. federal government announced Tuesday. The U.S. General Services Administration sold the Chet Holifield Federal Building, a one-million-square-foot office campus on 92 acres at 24000 Avila Road, to Health Care Development, LLC, an affiliate of Hoag Memorial Hospital Presbyterian. The sale is considered one of the largest redevelopment opportunities in South Orange County.