* Sprint slides on regulatory concerns, T-Mobile edges lower
* McDonald's jumps as global same-store sales beat estimates
* March core PCE up 1.9 pct yoy; in-line with estimates
* Futures up: Dow 0.53 pct, S&P 0.23 pct, Nasdaq 0.3 pct (Adds details, updates prices)
By Sruthi Shankar
April 30 (Reuters) - U.S. stock indexes were on track to open higher on Monday as strong earnings and a string of mergers lifted spirits, kicking off a busy week for inflation watchers.
Shares of oil refiner Andeavor jumped 12.2 percent in premarket trading after rival Marathon Petroleum agreed to buy the company for more than $23 billion. Marathon's shares were down 7.9 percent.
Investors are also keeping an eye on developments around the $26 billion takeover of Sprint by T-Mobile announced on Sunday, which needs to clear five regulatory hurdles.
Wireless carrier Sprint fell 11.7 percent, while T-Mobile edged 1.6 percent lower.
McDonald's jumped 4.1 percent after the company reported a better-than-expected rise in quarterly sales at its restaurants.
Allergan Plc rose 2.4 percent after its quarterly profit topped Wall Street estimates, driven by higher sales of its medical aesthetics products.
At 8:49 a.m. ET, Dow e-minis were up 128 points, or 0.53 percent. S&P 500 e-minis were up 6.25 points, or 0.23 percent and Nasdaq 100 e-minis were up 20 points, or 0.3 percent.
"If the previous several weeks of earnings season are any indication, corporate results should continue to act as a buffer to any meaningful turn lower in equity markets," noted Peter Kenney, senior market strategist at Global Markets Advisory Group, in New York.
"However, the principal threat to equity markets remains rising interest rates."
The main U.S. indexes are on track to record their first monthly gain since January, as strong quarterly earnings take the lead even as investors weigh concerns about rising interest rates and inflation.
Warnings from some large U.S. manufacturers about escalating costs going forward had investors worried that the best was over for corporate America.
Of the 267 S&P 500 firms that reported first-quarter earnings as of Friday, 79.4 percent topped profit expectations, according to Thomson Reuters data. That lifted the estimate for earnings growth to 24.6 percent from about 18 percent at the start of the season.
U.S. Treasury Secretary Mnuchin told Fox Business that President Donald Trump has not made any decision yet on tariff exemptions on metal imports.
The exemptions, which were granted to the European Union, NAFTA partners Canada and Mexico, as well as Argentina, Brazil, Australia and South Korea, will expire on May 1.
Focus will be on the Federal Reserve, when it meets on May 1 and 2 to discuss monetary policy. Though the central bank is not expected to raise rates, investors will be on the watch for clues about inflation and the pace of future rate hikes. The U.S. payrolls data for April is due on Friday.
Consumer prices as measured by the personal consumption expenditures (PCE) price index jumped 2 percent in the year to March, but on a core basis — the Fed's favored gauge of inflation — it rose 1.9 percent, in line with estimates. (Reporting by Sruthi Shankar in Bengaluru; Editing by Shounak Dasgupta)