Jan. 21 (Bloomberg) -- New York Times Co. is restricted from selling or transferring certain of its assets under the terms of a $250 million loan from companies controlled by Mexican billionaire Carlos Slim.

The New York-based publisher will also be limited in its ability to merge or consolidate with other companies, according to a securities filing today.

Any of the $225 million the company is trying to raise through sale-leaseback of its Manhattan headquarters would have to be used to refinance existing debt, according to the filing.

The company had been seeking to sell assets, trim staff and increase revenue through front-page advertisements as it faces a $400 million credit line expiration in May. Circulation and advertising have plunged as readers turn to the Internet for news.

Slim’s companies will receive more than 14 percent interest on the loan, which may add up to as much as $35 million annually, according to estimates by Barclays Capital Research. The companies, Banco Inbursa SA and Inmobiliaria Carso, also received warrants to buy as much as 17 percent of New York Times’ shares.

The publisher is seeking a buyer for its 17.5 percent stake in the Boston Red Sox baseball team, according to a person familiar with the talks. It is also trying to convince about 50 employees to take voluntary buyouts at its Boston Globe newspaper.

New York Times gained 9 cents to $6 at 4:15 in New York Stock Exchange composite trading. The shares declined 60 percent in the past 12 months.

To contact the reporter on this story: Greg Bensinger in New York at gbensinger1@bloomberg.net

Last Updated: January 21, 2009 18:10 EST