Singapore today insisted on the extradition of Nick Leeson, the jailed rogue trader whose speculating brought down Baring Bros. & Co., Britain's oldest merchant bank. Leeson desperately wants British authorities to indict him so that he can avoid 14 years in the infamous Singaporean prison system. But Michael Brunton reports from London that Leeson's effort to save himself, by telling his side of the story in an exclusive BBC interview by David Frost to be aired tonight, has backfired. "The Serious Fraud Office doesn't have much interest in bringing Leeson back here," Brunton says. "Despite his and his wife's recent public relations blitz, Leeson doesn't seem to have the sympathy of either the government or people on the street."