(Adds Petrobras, Curro, Saudi Aramco, Beijing Soft Rock, Macom, Oracle, LSE, Sunoco, Cukurova, Marathon Petroleum, Opera Software; Updates Aixtron)
Nov 21 (Reuters) - The following bids, mergers, acquisitions and disposals were reported by 1500 GMT on Monday:
** Novartis is buying U.S.-based Selexys Pharmaceuticals in a deal worth up to $665 million, the Swiss drugmaker said, expanding its pipeline of medicines to combat blood diseases.
** Symantec Corp said it would acquire U.S. identity theft protection services company LifeLock Inc for $2.3 billion, in a deal that it hopes will prop up sales at its Norton cybersecurity unit.
** China's Anbang Insurance Group Co is in talks to buy as much as $2.3 billion in Japanese residential property assets from Blackstone Group, two people involved in the discussions said, in what would be Japan's biggest property deal since the global financial crisis.
** Boral Ltd, Australia's biggest supplier of building materials, said it would buy Headwaters Inc for $1.8 billion in cash, doubling its U.S. presence at a time when President-elect Donald Trump plans a huge jump in infrastructure spending.
** South Africa's second-largest private hospital firm Netcare will buy Akeso Clinics, a chain of psychiatric health facilities, for 1.3 billion rand ($91 million), the firm said.
** South Africa's biggest private education firm Curro Holdings, acquired a 50 percent stake in Botswana-based BA Isago University as part of its stated goal to run 80 campuses by 2020, the firm said on Monday.
** Brazil's state-controlled oil company Petroleo Brasileiro SA said in a securities filing on Monday that an injunction in a civil lawsuit has forced the company to suspend the sale of stakes in the Baúna and Tartaruga Verde oil fields.
** Rowan Companies Plc said it was forming a joint venture with Saudi Arabian state oil giant Saudi Aramco to operate offshore drilling rigs in the country.
** Concerns over China gaining access to the secrets of producing a little known material used in military equipment appear to be behind the U.S. block on a 670 million-euro ($713 million) Chinese bid for German chip equipment maker Aixtron .
** Beijing Soft Rock Investment Group said on Monday it had scraped an asset-swap deal with Dalian Wanda Group, which is seeking a backdoor listing for its commercial property business in Shanghai.
** Analog chipmaker Macom Technology Solutions Holdings Inc said on Monday it would buy fellow chipmaker Applied Micro Circuits Corp for about $770 million to expand its data center connectivity business.
** Business software maker Oracle Corp said on Monday it would buy Dyn, a monitor of global internet performance and traffic, to allow cloud customers to optimize their infrastructure costs and increase web-driven revenue.
** London Stock Exchange Group Plc (LSEG) said on Monday that it would acquire business and financial information provider Mergent Inc.
** Sunoco Logistics Partners LP said it would buy Energy Transfer Partners LP ETP.N in a deal valued at $19.93 billion to create the second-largest master limited partnership by enterprise value.
** Turkish holding company Cukurova did not declare an intent to buy a 13.22 percent stake in Turkcell from Russia's Alfa Telecom by a Nov. 18 court deadline, a source close to the matter told Reuters.
** Hedge fund Elliott Management, which owns about 4 percent of Marathon Petroleum Corp, urged the company to conduct a strategic review and consider splitting into three businesses.
** Norway's Opera Software no longer plans to buy or sell companies and will instead stay focused on developing its mobile advertising units after the recent divestment of a key business, chief executive Lars Boilesen told Reuters on Monday. (Compiled by Laharee Chatterjee in Bengaluru)