Amex Chief Resigns to Run Thermo Electron

Richard Syron, the head of the American Stock Exchange, on Monday was named chief executive of Thermo Electron Corp., the Boston-based parent firm of a legion of technology companies.

Syron, a Boston native, steps down as Amex chief about a year after the No. 3 U.S. exchange was absorbed by its No. 2 rival, the National Assn. of Securities Dealers, the parent of Nasdaq.

Syron, 55, has been chairman of the Amex since 1994.

Thermo Electron is the parent of about 15 tech firms, which all are listed on the Amex. But the parent’s shares, which fell 19 cents to $14 Monday, are on the Big Board.