Loews to Buy Entergy-Koch Pipeline  NEW YORK (Reuters) - Conglomerate Loews Corp. &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=LTR.N target=/stocks/quickinfo/fullquote"&gt;LTR.N&lt;/A&gt;  agreed to buy an 8,000-mile natural gas pipeline system from  Entergy-Koch LP for \$1.14 billion on Monday, in a bid to cash  in on rising U.S. demand for natural gas.