In the latest sign of how lower demand is hitting parts of the U.S. office market, one of the tallest towers in St. Louis that sold for $205 million in 2006 has changed hands again this week — for about $3.6 million.

The former One AT&T Center, a 44-story high-rise totaling 1.46 million square feet at 909 Chestnut St., is now owned by Boston-based Goldman Group. The firm bought the property via CoStar Group's Ten-X auction exchange from SomeraRoad Holdings, a commercial real estate investor and developer that paid just $4.5 million for it two years ago. On a per-square-foot basis, the tower's value over 18 years dropped from about $140 to $2.50, according to CoStar data.