US STOCKS-Futures point to lower open but quarterly rise
* Oil prices weaken for third straight day, Exxon down early
* Charter to buy Bright Hose for about $10 bln
* Investors looking ahead to consumer confidence data
* Nasdaq set for longest streak of quarterly gains ever
* Futures down: Dow 88 pts, S&P 10.5 pts, Nasdaq 20 pts (Updates prices)
By Ryan Vlastelica
NEW YORK, March 31 (Reuters) - U.S. stock were poised to open lower on Tuesday, indicating a modest retreat from the previous session's rally, though the S&P 500 remained on track for its ninth straight quarterly rise.
Energy shares will continue to be in focus as crude oil fell 1.3 percent to $47.58 per barrel, sending Exxon Mobil Corp down 0.6 percent to $85.10 in premarket trading. Oil is set for its third straight daily decline, losing more than 7 percent in the three days. U.S. crude futures were volatile on Monday, swinging between a gain of 0.6 percent and a decline of 2.6 percent.
On Tuesday, oil was pressured as Iran and six world powers entered a final day of talks on a nuclear deal that could see the energy-rich country increase oil exports. The talks come at a time when oversupply is already a major concern for energy investors, having contributed to crude falling more than 50 percent from a high in June. Continuación...