The 145,170-square-foot loft office building at 250 W. 54 St. in Midtown’s Theater District was purchased by Zar Property NY for $83.1 million.

Paul Davidson, Roy Lapidus and Chip Porter of Newmark Grubb Knight Frank represented the seller, Ascot Properties. The deal for the building between Broadway and Eighth Avenue works out to roughly $572 per square foot and closed during last Thursday’s snow storm.

Along with a multilevel Crunch fitness facility and other small retailers, the current office tenancy is theater- and entertainment-related.

That mix is likely to change as the local family ownership begins a cap improvement program geared toward making it more TAMI tenant friendly.

The block used to house Studio 54 but was in the doldrums until recently. Now, Stephen Colbert hosts “The Late Show” at the nearby Ed Sullivan Theater, while new hotel and the Boston Properties office building at 250 W. 54 St. have brought a resurgence of upscale foot traffic. “I have worked with that building for 20 years and the block used to be dead and it is now revitalized,” said Davidson.

NGKF’s parent company, BGC Partners, submitted a draft registration statement to the SEC last week for an IPO.