NEW YORK CITY-Boston Properties, which has been looking for the past few months to refinance the former Citigroup Center tower at 601 Lexington Ave., appears to have concluded its search. Commercial Mortgage Alert reported Friday that a club deal involving MetLife, Prudential Mortgage and New York Life has been struck for a $700-million, 10-year loan on the 1.6-million-square-foot office property, now known simply by its street address. A spokeswoman for BXP declines to comment on the report and GlobeSt.com calls to the insurers were not returned by deadline Friday.

The Boston-based REIT reportedly has shopped around for a loan since last fall, mainly to retire debt on 601 Lexington that is due to mature this coming May. The property’s relatively low leverage and solid fundamentals made it appealing to insurers, according to CMA.

In a January conference call discussing BXP’s fourth-quarter 2010 results, Michael LaBalle, the REIT’s SVP and CFO, commented, “We adjusted our end market to refinance our $455-million mortgage loan on 601 Lexington Ave. As we’ve mentioned before, the cash flow of this building has increased substantially since our acquisition in 2001,” when BXP and affiliates of Allied Partners paid a total of $755 million to buy it from Dai-Ichi Life Investment Properties. “And we anticipate raising additional proceeds with a $700-million to $750-million new loan, which is still a sub-50% leverage position.” Later in the call, LaBalle said that an additional $250 million to $300 million in proceeds from the loan would help “supplement our liquidity” after paying off the mortgage on 601 Lexington.

In announcing the April ’01 acquisition of what was then known as Citigroup Center, BXP said it had obtained a $525-million loan from an affiliate of Deutsche Bank. According to SEC filings, the loan carried a fixed rate equal to 7.1855% and a May 11, 2011 maturity date. BXP provided $195 million of equity in the deal, with the Allied affiliates providing the remaining $35 million, according to BXP's Q2 ’01 report.

This past December, CMA reported that BXP had had preliminary conversations with balance-sheet lenders, and noted that the CMBS market was likely to go after the assignment as well. Six months earlier, GlobeSt.com reported that the Durst Organization had refinanced the Bank of America Tower at 1 Bryant Park in part with a comparably sized package of securities worth $650 million, with the other half of the $1.3-billion refi coming from tax-exempt bonds. And in November, GlobeSt.com reported that the Bank of China had provided the seven-year, $800-million loan to refinance Brookfield Office Properties’ 245 Park Ave.

However, the assignment in the end evidently went to insurers, a lending sector that has become more active lately. That being said, insurance companies remain among the most conservative of lending sources, as evinced by the Mortgage Bankers Association report earlier this month which found that life companies’ 60-day mortgage delinquency rate was 0.19%, compared to 4.19% for banks. In the case of BXP and 601 Lexington, the strength of the sponsor along with the property’s fundamentals was likely a draw: according to its 2010 annual report, the REIT has a market cap of approximately $13 billion.