NEW YORK – Ruby Tuesday is being acquired for about $146 million in a deal that will take the struggling chain private.

Like other sit-down restaurant chains, Ruby Tuesday has lost customers to cheaper, faster and more casual places. Comparable-store sales at Ruby Tuesday have fallen for six consecutive quarters and the company has not reported a quarterly profit in two years, even as it has made tweaks its menu and made small changes, like adding salad bars, in an attempt to boost traffic.

The private-equity firm NRD Capital said Monday that it will pay $2.40 for each share, a 21 percent premium from the chain’s closing price of $1.99 on Friday. When debt is included, the companies value the deal at $335 million. Ruby Tuesday, which has about 600 restaurants, said in March that it was considering a buyout.

Atlanta’s NRD is already in the restaurant business: It acquired Frisch’s Big Boy Restaurants in 2015 and bought a majority stake in Fuzzy’s Taco Shop last year. It has invested in other chains as well.

Shares of Ruby Tuesday Inc., based in Maryville, Tennessee, rose 38 cents to $2.37 on Monday.