NYSE trader
Traders work on the floor of the New York Stock Exchange on May 6, 2016. REUTERS/Brendan McDermid

Wall Street ended mixed on Monday after a rally in Allergan Plc and other healthcare companies offset a decline in energy shares.

Five of 10 S&P sectors ended higher, led by the health sector's 1.13 percent increase, while energy and materials sectors both tumbled 1.25 percent.

Allergan surged 5.98 percent. Teva Pharmaceutical Industries Ltd. said it still expected its $40.5 billion acquisition of Allergan's generic drug business to close in June.

Chevron Corp. fell 1.48 percent as U.S. crude prices dropped 2.8 percent and traders assessed the impact of wildfires on Canada's oil output and a build in inventory.

A bigger-than-expected drop in China's imports and exports in April pointed to weak demand in the world's second-biggest economy and weighed on materials stocks. Caterpillar dropped 3.52 percent, weighing the most on the Dow industrials.

Investors remain cautious about corporate earnings. With first-quarter reports almost all in, earnings at S&P 500 companies, on average, fell 5.5 percent while revenue was down 1.9 percent, according to Thomson Reuters I/B/E/S.

"I would give this earnings season a C or C-. While most of the companies were able to step over a greatly reduced bar of expectations, overall sales growth remains disappointing," said Alan Gayle, senior investment strategist at RidgeWorth Investments in Atlanta, which has $50 billion in assets under management.

The Dow Jones industrial average ended down 0.2 percent at 17,705.91 points while the S&P 500 edged up 0.08 percent to 2,058.69.

The Nasdaq Composite added 0.3 percent to 4,750.21, helped by a 2.45-percent rally in the Nasdaq biotech index.

Krispy Kreme Doughnuts Inc. jumped 24.32 percent to after agreeing to be taken private for $1.35 billion.

That made investors hungry for other restaurant stocks, including Kona Grill, up 8.18 percent, and Pollo Loco, up 5.02 percent.

Shares of Lending Club Corp. tumbled 34.93 percent. The chief executive officer of the world's biggest online lending platform resigned following an internal probe.

Wayfair Inc. jumped 10.17 percent after the online furniture retailer reported first-quarter sales that beat analysts' estimates.

Declining issues outnumbered advancing ones on the New York Stock Exchange by 1,594 to 1,407. On the Nasdaq, 1,486 issues rose and 1,322 fell.

The S&P 500 index showed 33 new 52-week highs and four new lows, while the Nasdaq recorded 47 new highs and 53 new lows.

About 6.8 billion shares changed hands on U.S. exchanges, below the 7.2 billion daily average for the past 20 trading days, according to Thomson Reuters data.