In one of his first major steps since being named chief executive of struggling Maguire Properties Inc., Nelson Rising will try to raise hundreds of millions of dollars by selling Park Place, a 105-acre office park and development site in Orange County, Calif., that had been a pet project of founder and former Chief Executive Robert Maguire III.

Maguire Properties, a large owner of California office buildings, also will raise $100 million to $110 million of much needed cash by adding debt to its Plaza Las Fuentes, a mixed-use property, and Westin Pasadena Hotel, both in Pasadena.

Maguire's L.A. properties

In addition, the company announced Monday that its chief financial officer, Martin Griffiths, and two other senior executives -- Paul Rutter, head of major transactions, and William Flaherty, who oversees marketing -- will be leaving the company.

In the interim, Chief Accounting Officer Shant Koumriqian will assume responsibility for accounting and reporting matters. Douglas Gardner, recently appointed executive vice president, will take over responsibility for areas including asset management, leasing and development.

Mr. Rising was brought in to run Maguire last month after a tumultuous year in which the company's financial condition deteriorated and Robert Maguire struggled with pressure to sell assets from hedge funds that had acquired more than 60% of the company. Mr. Maguire, who tried at one point to buy the company himself, stepped down as chairman and CEO after his most recent effort to salvage control collapsed.

Mr. Rising, best known for his success at turning around Catellus Development Corp. in the 1990s, said in an interview Sunday that he also is considering selling other Orange County properties and is talking to creditors about restructuring debt on some of Maguire's poorly performing properties. "We have significant challenges on many of our buildings," he said.

At this point, Mr. Rising says Maguire has no plans to sell any of its buildings in downtown Los Angeles, where Maguire is the largest owner of institutional-quality office space. He predicted that demand for that space will rise because of attractive rents and access to public transportation, a more important factor with gas prices soaring.

Maguire's biggest problem is its crushing $5 billion debt load, much of it taken on to finance the ill-timed acquisition of Orange County office buildings last year just before the market turned south. Even with Maguire's recent decision to stop paying a dividend, the company isn't generating enough cash to pay its debt service.

Maguire purchased Park Place in 2004 for about $475 million. It houses the former headquarters of Fluor Corp. and land for additional office, retail and residential development. Before Robert Maguire left, he described it as a key element to the company's Orange County strategy.

Maguire's hedge-fund investors, which have been concerned that the company might try to improve liquidity by selling stock, will likely be relieved. "We think they can enhance liquidity strictly by doing asset sales," said Jon Brooks, general partner of JMP Capital Partners LP, a hedge fund that owns about 8% of Maguire.

--Mike Barris contributed to this article.

Write to Peter Grant at peter.grant@wsj.com

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