Before the game, Bettman told reporters that talks to sell the cash-strapped Sabres are moving forward. The NHL took control of the team when owner John Rigas and two sons were indicted on fraud charges following the collapse of Adelphia Communications.
Among the potential buyers are Rochester billionaire Tom Golisano, who just completed an unsuccessful campaign for New York governor and Mark Hamister, who owns the Buffalo Destroyers of the Arena Football League.
Neither buyer could not have been happy when Thornton made it 1-0 just 21 seconds into the first period.
The Sabres outshot the Bruins, 11-5, over the opening 20 minutes and forged a 1-1 tie when J.P. Dumont beat Steve Shields on a breakaway with 6:06 remaining.
But Boston scored three times on four shots in a 5:38 span of the second period, chasing rookie Mika Noronen on P.J. Axelsson's goal with 12:22 remaining.
The Sabres made it respectable over the final four minutes on a pair of goals by Chris Gratton but fell to 0-7-2 in their last nine games.