The Nasdaq OMX Group Inc. (Nasdaq: NDAQ) has agreed to acquire eSpeed, operator of a fully executable central limit order book for electronic trading in U.S. Treasuries, from BCG Partners (Nasdaq: BGCP). The deal is valued at $750 million in cash, plus certain contingent issuances of stock that approximate certain tax benefits to NASDAQ OMX.

Aquilex, a portfolio company of Centerbridge Partners, has sold its Specialty Repair and Overhaul business to AZZ Inc. (NYSE: AZZ). No financial terms were disclosed.

Attune Consulting, a global provider to solutions to the fashion and lifestyle industries with a U.S. office in Burlington, Mass., has raised $20 million from Sri Lankan apparel maker MAS Holdings.

Carl Icahn has acquired a 9.27% stake in speech recognition software company Nuance Communications (Nasdaq: NUAN), according to a regulatory filing.

ConnectSolutions, a San Francisco-based private cloud service provider of unified-communications-as-a-service solutions for large enterprise and government organizations, has acquired NextUC, a provider of Microsoft Lync-based UC solutions for streamlining SME communications. No financial terms were disclosed. ConnectSolutions recently raised $10 million in VC funding from Frontier Capital.

Hess Corp. (NYSE: HES) has agreed to sell its Russian subsidiary Samara-Nafta to Lukoil for approximately $2.05 billion.

Perrigo Co. (Nasdaq: PRGO) has acquired Velcera Inc., a Yardley, Penn.-based pet health products company, for approximately $160 million in cash.

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