The families of Chinese real estate developer Zhang Xin and Brazil's Safra banking empire bought a 40 percent stake in New York's General Motors Building for about $1.4 billion, a person with knowledge of the deal said.

Zhang is the billionaire founder and chief executive officer of Soho China Ltd., the biggest developer in Beijing's central business district. Her family and M. Safra & Co., the New York-based investment firm of the Safra family, bought the stake through an entity called Sungate Trust, said the person, who asked not to be named because the details are private.

The price implies that the 2 million-square-foot (185,800- square-meter) tower is valued at about $3.4 billion, the highest total value for a U.S. property since the GM Building sold in 2008. The 50-story, white marble-clad building at 767 Fifth Ave. near the southeast corner of Central Park is one of the most recognizable office buildings in the U.S. and is known for its Apple Inc. store at street level.

The sellers were Goldman Sachs Group Inc.'s U.S. Real Estate Opportunities Fund, which invests on behalf of the sovereign wealth funds of Kuwait and Qatar; and Meraas Capital LLC, a Dubai-based private-equity firm, the person said. The sale was completed on May 31, according to the person. The deal was reported earlier Sunday by the Wall Street Journal.

Boston Properties

Darcy Stacom and Bill Shanahan, brokers for CBRE Group Inc., handled the transaction. Boston Properties Inc. retains a 60 percent stake in the building and manages it. Arista Joyner, a spokeswoman for the Boston-based landlord, didn't immediately respond to an e-mail and call placed outside of regular business hours.

Robert McGrath, a spokesman for CBRE, declined to comment on the sale. Andrea Raphael, a spokeswoman for Goldman Sachs, didn’t immediately respond to e-mails sent outside regular business hours. M. Safra, Soho China and Meraas representatives also weren't immediately reachable by phone or e-mail.

The GM Building occupies the full block between Fifth and Madison Avenues and 58th and 59th Streets. It was built in 1968 and designed by architect Edward Durell Stone. Tenants include Estée Lauder Cos., Icahn Enterprises and the law firm Weil, Gotshal and Manges.

A property across the street, 650 Madison Ave., is under contract to be sold for $1.3 billion to Crown Acquisitions Inc. and Highgate Holdings Inc., Crown said Saturday. That purchase is the largest of an entire building in the U.S. since 2010.