Sun Pharmaceuticals said Monday it is acquiring Ranbaxy Laboratories, the generics drugs maker currently owned by Japan's Daiichi Sankyo, for around $3.2 billion, making it the Asia-Pacific's largest deal in the sector this year. Sun Pharma, a company born in Calcutta in 1983 but is now run out of Mumbai, will become the largest pharmaceutical company in India, and the fifth-largest specialty generics company in the world following the acquisition.