Drexel University has spent $21.8 million to buy 3.6 acres on the north side of the 3000 block of John F. Kennedy Boulevard, between the school's West Philadelphia campus and 30th Street Station.The purchase of the land from a group of California investors, currently operated as the Five Star asphalt parking lot, will allow Drexel to add academic classroom and research, and commerical office, retail and residential developments with "24 hour" uses at the school's eastern end, helping link the campus to Center City, university president John Fry told me.Fry says he's begun approaching developers, including Brandywine Realty Trust, which built the neighboring Cira office tower in the mid-2000s, about possible projects. Drexel trustees are drafting a master plan for the campus that would include the site. He credited former trustee chairman George Ross with the previous purchase of the nearby Evening Bulletin building south of the Five Star purchase. Fry also said he's talking to Amtrak about possible expansion over the nearby train yards. Drexel is the latest West Philly institution to expand toward Center City. See previous plans by Penn and CHOP.