Dennis B. Levine began serving a prison sentence.

Levine, the Wall Street insider trading figure who led investigators to Ivan F. Boesky, is serving a two-year sentence at Lewisburg Federal Penitentiary in Pennsylvania. Levine, a former trading partner in Drexel Burnham Lambert Inc., will serve his sentence in a minimum-security section of the prison, Clifford Kinney, executive assistant to the prison warden, said. Levine pleaded guilty in June, 1986, to charges of securities fraud, tax evasion and perjury and settled civil charges by agreeing to pay $11.6 million and to cooperate with the government’s investigation.