Sept 19 (Reuters) - Some longtime traders at Point72 Asset Management have left the firm, including Chandler Bocklage, who was billionaire Steven Cohen's trading assistant, the Wall Street Journal reported, citing sources familiar with the matter.

Three other portfolio managers - Anthony Chedid, Ted Orenstein and Tom Rabolli - have also quit Point72, the newspaper reported. (http://tinyurl.com/nzfthrp)

Point72 also closed its Boston office, retaining only some compliance staffers. Steven Rosen, a fundraiser and recruiter who ran the Boston office, left last week, the report said.

All the five employees were veterans of SAC Capital Advisors LP, the predecessor to Point72 that pleaded guilty to insider-trading charges last year, and were described as being close to Cohen, the newspaper said.

The Journal said a Point72 spokesman on Thursday confirmed the departures and described them as part of routine employee turnover.

Earlier this month Mathew Martoma, a former portfolio manager at SAC Capital, was sentenced to nine years in prison for engaging in what authorities called the most lucrative insider trading scheme in U.S. history.

SAC Capital recently changed its name to Point72 Asset Management, and was transformed into a family office managing the assets of its founder Cohen.

(Reporting By Shivam Srivastav in Bangalore; Editing by Gopakumar Warrier)