* Endo up after agreeing to buy Par Pharmaceutical
* Altera, Ann rises on possible deals
* S&P closed at record-high on Friday
* Futures down: Dow 22 pts, S&P 4.25 pts, Nasdaq 15.25 pts (Adds details, comment, updates prices)
By Sweta Singh
May 18 (Reuters) - U.S. stocks were set to open lower on Monday after a stream of weak economic data over the last week muddied the outlook for U.S. interest rates, making investors wary of taking big positions.
The market will get another clue on the state of the economy at 10 a.m. ET (1400 GMT) when the National Association of Homebuilders releases its monthly homebuilder confidence index.
If the index does not rise, as expected, stocks could rally, said Adam Sarhan, chief executive of Sarhan Capital in New York.
The U.S. economy is struggling to rebound strongly enough for the Federal Reserve to raise interest rates before September, analysts have said.
Data released on Friday showed that industrial output slipped and consumer sentiment fell. The S&P gained 0.08 percent to close at a record high of 2,122.73, modestly exceeding its previous peak on April 24.
The Federal Reserve could look at a rate hike in June if the economy is strong enough, Chicago Fed President Charles Evans said on Monday, although he argued for rates to start rising in early 2016.
S&P 500 e-mini futures were down 4.25 points and their fair value - a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract - indicated a lower open.
Dow Jones industrial average e-mini futures fell 22 points and Nasdaq 100 e-mini futures lost 15.25 points.
Endo International's shares rose 1.21 percent to $86.38 in premarket trading after the generic drugmaker said it would buy privately held Par Pharmaceutical from TPG Capital in a $8.05 billion deal.
Altera rose 6.4 percent to $47.26 after the New York Post reported that the company had resumed talks with Intel on a possible deal. Intel was little changed.
Ann Inc gained 22.5 percent to $47.44 after the company agreed to be bought by Ascena Retail for $2.15 billion in cash and stock.
Las Vegas Sands fell 1.16 percent to $50.38 after Goldman Sachs cut its rating on the stock to "neutral".
Yelp fell 2.2 percent to $45.86 after Piper Jaffray cut its rating on the stock to "neutral" from overweight".
Alibaba fell 1.2 percent to $87.20 after a group of luxury goods makers sued the company on Friday, contending that the Chinese e-commerce giant knowingly made it possible for counterfeiters to sell their products throughout the world. (Additional reporting by Tanya Agrawal in Bengaluru; Editing by Saumyadeb Chakrabarty)