The former president of a foundation that prosecutors say has a history of legal entanglements over its alleged ties to Iran's government pleaded guilty Wednesday to obstruction. Farshid Jahedi, the ex-president of the Alavi Foundation, said during his plea in US District Court in Manhattan that he tore up and threw away documents that he knew would be subject to a subpoena issued in connection with a grand jury investigation. In court papers, Assistant US Attorney Harry A. Chernoff wrote that the government last year filed a forfeiture complaint alleging that the Alavi Foundation's sole partner in the ownership of a Fifth Avenue office tower was actually a shell company fronting for a secret interest held by Bank Melli, the state-owned bank of Iran. The government at the time alleged that the monetary transfers by the shell company, Assa Co., to Bank Melli violated money-laundering statutes because the bank is owned by the Iranian government, which is designated by the US as a sponsor of international terrorism. Chernoff said the setup gave "the government of Iran a secret interest in a major revenue stream in the United States, where Iran's financial activities have been heavily restricted since the 1979 Iranian revolution." The prosecutor said a surveillance team spotted Jahedi discarding ripped-up documents that were "clearly responsive to the grand jury's demand" the day after federal agents told Jahedi in his office that he was not permitted to destroy any documents requested by the subpoena. Judge Shira Scheindlin said sentencing guidelines call for Jahedi to receive up to 1 1/2 years in prison and a fine of up to $30,000. Sentencing was set for April 2. Jahedi, 55, remains free on bail. During his plea to obstructing justice and impairing a document's availability for an official proceeding, Jahedi said he had received master's degrees in architecture from the National University of Iran in 1978 and from the University of Pennsylvania in 1981.