A group led by British investor Brian...

A group led by British investor Brian Beazer and Shearson Lehman Hutton sweetened its buyout offer for Koppers Co. by more than $200 million, to about $1.52 billion, the Pittsburgh-based construction materials and chemical company said. Koppers board, which last week rejected the group’s initial $45-a-share offer and said it would explore defensive alternatives, said it will consider the new $56-a-share proposal. Koppers stock rose 12.5 cents to $53.75 a share Friday on the New York Stock Exchange.