Xstrata shares took a hit on Tuesday after a report that the mining company had rejected a $76 billion takeover approach from Brazilian rival Vale and that its suitor was close to walking away. The Financial Times quoted people close to the matter as saying London-listed Xstrata and its 35-percent shareholder, Swiss commodities trader Glencore, had rejected a cash-and-shares proposal pitched at just under 40 pounds a share and were holding out for about 45 pounds a share. The market isn’t so sure that a richer offer is forthcoming: Xstrata shares fell 2.4 percent to 37.15 pounds, one of the biggest losers on the FTSE 100.

Activist investor Ralph Whitworth of Relational Investors LLC is in advanced discussions to take a seat on the board of Sprint Nextel Corp, according to several reports. Relational Investors has a 1.9 percent stake in Sprint and has been pressing for strategic change as the U.S. No. 3 wireless operator has lost market share. Whitworth has already shown that his opinions carry some weight — Last October, he threatened a proxy battle unless Sprint dealt with its leadership. CEO Gary Forsee stepped down later that month.

New York developer Harry Macklowe has been served with a notice of default related to  four properties, in a move that could eventually lead to foreclosure, according to a report in the Wall Street Journal. Macklowe has been negotiating with lenders including Vornado Realty Trust over a total of $7 billion of debt on seven Manhattan buildings, but the possibility of a foreclosure action has increased because negotiations on the debt have bogged down.