Normandy Partners and New York Life are in contract to buy the office building at 575 Lexington Ave. between 51st and 52nd streets in the Plaza District for about $360 million, sources said.

The 740,000-square-foot building is being sold by CalSTRS and Silverstein Properties — which bought it in 2006 for $416 million from the Koeppel Cos., and then made further capital improvements.

The mortgages were recast after the 2008 downturn.

Developed in 1958 by Sam Minskoff & Sons, the 35-story building was redeveloped in 1990 by the Koeppels in a renovation overseen by the late architect Der Scutt.

The tower floors are vacant and, according to CoStar, there is a 250-car garage and a New York Sports Club in the building. Other major tenants include: the financial firm Janney Montgomery Scott, with 41,500 square feet; Cornell University, with over 130,000 square feet; and the law firm Boies Schiller & Flexner, with 100,000 square feet.

The pricing equates to about $485 per foot. In March, Henry Elghanayan of Rockrose walked away from a tentative deal for $10 million more, or $370 million.

Doug Harmon and Adam Spies of Eastdil Secured marketed the property and are also beginning to market Worldwide Plaza, which will likely sell for around $1.5 billion.

Normandy, based in Morristown, NJ, bought 1370 Broadway in April for $123.75 million and has been an active investor.

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Zeil Feldman is closing today on the loft office building at 11 Beach St. in Tribeca. So far, no pricing is available.

The 10-story L-shaped building also has an address of 30-32 Varick St. and faces St. John’s Lane and therefore has great light and air.

The 125,000-square-foot building is primarily occupied by the Art Institute of New York City whose lease ends in December 2013. The 1910 building was last renovated in 1988.

In a statement, Feldman, head of HFZ Capital, said, “We will deliver large, loft-style apartments containing multiple exposures and open views.”

The property was sold by Prince Realty Advisors and Leonard Kahn.

Tribeca has a hot residential market and the seven-story corner condo at 19 Beach St. that was built and tucked inside the “L” in 2001 has a 3,105-square-foot sun-drenched full floor loft available for $3.595 million through Prudential Douglas Elliman.

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The hip streetwear brand, Superdry USA, worn by the likes of Justin Bieber, will be opening its fourth city shop in August, at 716 Lexington Ave. in the former Payless Shoe Source and Genesis location by Bloomingdale’s.

The store has 2,600 square feet on the ground, 2,500 square feet on the second floor and 1,800 square feet on the lower level.

Bert Dweck and Chris DeCrosta of Thor High Street represented Superdry in the deal, while RKF’s Ariel Schuster and Justin Fantasia represented Payless in the five-year sublease.

Conceived in 2003 by James Holder and Julian Dunkerton after a trip to Tokyo, Superdry wanted a distinct space in a prime location with lots of foot traffic. The building is owned by a Sol Goldman Estate entity.

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A former celebrity recording mecca is becoming a celebrity catering joint.

Caterer Peter Callahan just bought the 5,940-square-foot fourth floor from Sony in the West 25th Street building that previously housed Jive Records and recording studios where Britney Spears, Justin Timberlake and Whitney Houston got their start.

Callahan will now build out a full kitchen, design studio and event space with soaring ceilings for his clients, who include Martha Stewart, Regis Philbin, Kelly Ripa and Tom Petty along with uber-wealthy financiers.

Robert Burton, Brock Emmetsberger and Andrew Essick of Massey Knakal marketed the building’s floors on behalf of Sony, and Callahan nibbled down his price to $2.1 million. Two other floors are in contract, sources said.

Chris Halliburton and Brandon Himmel of The Corcoran Group represented Callahan in the deal.

Just in time for your own summer food solutions, Callahan’s new “Bite by Bite” book features “100 Stylish Little Plates You Can Make for Any Party.”

Sony took over Jive in 2008 and inherited the 12-story, 72,000-square-foot building at 137 W. 25th St. that was divided into office condos in 1987 and has been owned and used by Arista and Zomba Records.

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If you think the rent is too damn high now, wait a couple of years.

Developers complain that land costs are so high now, they are penciling in rents of $80 a square foot — or $6,666 per month for future 1,000-square-foot apartments.

At a forum yesterday organized by accountants Margolin, Winer & Evens, their clients Gary Barnett of Extell Development, David Picket of the Gotham Organization and Peter Duncan of George Comfort & Sons all complained about finding deals and a growing land-price bubble.

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Our sincere condolences to all at Winoker Realty Co. and the family of David Winoker, the beloved executive who died last Friday in the terrible upstate skydiving accident along with his instructor, Brooklynite Alexander Chulsky.