TO simplify the ownership stack, and to get a jump on things before it gets a new $145 million mortgage from TIAA-CREFF, SL Green Realty is fiddling with several ground leases at the Graybar Building, Between the Bricks has learned.

While SL Green operates, manages and leases the building, as is typical in older city buildings, various groups hold ownership stakes in 420 Lexington Ave.

Public documents show that early last month SL Green bought out one of the ownership position from W&M Properties, which is led by Peter L. Malkin and his son, Anthony, for $7.6 million.

The Malkins had bought the passive position for $5.1 million and had been receiving rent payments.

The W&M lease position actually sat between two other SL Green positions. W&M had previously sold a fourth piece to MetLife.

“We are out there trying to clean up our liabilities and simplify these positions,” said an SL Green executive who was not authorized to speak on the record. “The Graybar financing was another piece of that strategy.”

SL Green’s existing mortgage was due next year. The company refinanced for a larger sum and was able to pull out $23 million.

Anthony Malkin said SLG had approached these other owners a few times over the years to sell their portion.

“We finally came to terms on something that made sense to us,” he said, adding his outfit has “good access to capital” but is sitting on the sidelines waiting for other market opportunities.

The deal with W&M is one of several that SL Green has struck with parties that own pieces of the building.

Other documents show that the SLG operating lease was amended in 2007 with the family of Henry Hart Rice. Sources said SL Green was given an option to extend the lease through 2075, which also made it easier to get the new mortgage.

*

Bob’s Discount Furniture has signed a deal to take 35,000 square feet at the upcoming 800,000-foot shopping mall, Sky View Center, at Sky View Parc in Flushing, Queens.

The lease with Muss Development is for 10 years.

Fred Feinblum and David Lucas of Julius M. Feinblum Real Estate repped the furniture chain, while John Hanlon of Ripco Real Estate negotiated for Muss

Bob’s Discount Furniture has 33 stores and will open at Sky View next spring.

*

At the other end of the design and décor spectrum is decorator Liz O’Brien, whose gallery is moving east from Fifth Avenue to First Avenue.

O’Brien is relocating to a 2,400-foot shop at the Interior Design Building at 306 E. 61st St. that was vacated by Historical Design, which consolidated into its loft warehouse. O’Brien will be joining other interior-designer tenants in the space, said Philip Carter, who owns the building along with Alan Schwartz in Urban Partners.

CoStar lists the asking rent at $135 a foot.

*

AIG sent us a note explaining that Gold man Sachs is reim bursing the bailed- out company for the 800,000 feet that AIG rents — but Goldman Sachs is occupying — at 180 Maiden Lane.

No one would supply numbers, but we’re happy that it appears taxpayers aren’t footing any of what could otherwise be a $75 million bill.

AIG will be moving in slowly as Goldman moves into its new headquarters at the World Financial Center.

[email protected]