The apartments are now available as a single unit or two, but it is hard to sell any property in today’s dim real estate market. Try one with a seven-figure price tag and a princess who does not want the deal to go through.  As the squabbling continues, and housing prices slide, the potential windfall for both sides has dwindled. A year ago, the asking price for the home, on the Pierre’s 30th and 31st floors, was $50 million; recently, the brothers were close to a deal on the larger of the two apartments for $18 million, according to a person familiar with the negotiations. (Tuesday’s complaint indicated that the buyer backed out because Princess Firyal “has made it clear that she intends to attack any potential sale.”)  “Princess Firyal’s repeated threats to interfere with the sale of the Pierre apartments has made it extremely difficult for Matthew S. Pincus and Henry Pincus to find a ready and willing buyer,” read the complaint, filed by the Pincuses’ lawyers at Schulte Roth & Zabel in Manhattan.  The current quarreling is an ugly chapter in what once seemed like a charming romance. Mr. Pincus, a principal at the investment firm E. M. Warburg Pincus, was a well-respected financier but hardly a socialite. After his first wife died of cancer, he met Princess Firyal, who was once married to an uncle of King Abdullah of Jordan and had also dated the shipping tycoon Stavros Niarchos.  Mr. Pincus, who, given his wealth, had lived relatively modestly — in a world where a 2,500-square-foot house in Southampton and a ranch in Utah count as modest — did an about-face upon meeting the princess, according to one friend, who spoke on the condition of anonymity because he did not want to be identified discussing his friend in the newspaper.  “It was the antithesis of the way Lionel lived with his first wife,” this person said. “Princess Firyal introduced Lionel to Europe, to Ascot, to royalty. He lapped it up. It amazed me.”  Mr. Pincus’s sons say the princess spent increasing amounts of his money even as his health deteriorated: in 2005, the filing says, she spent $9.31 million; in the first seven months of 2006, more than $5.4 million.  But Jim McCarthy, Princess Firyal’s spokesman, said she “has been the love of Lionel Pincus’s later life” and described the lawsuit’s assertions as “false, outrageous and without merit.”  This is not the first court battle over the apartment. Princess Firyal filed suit in 2007 to block any sale of the property, but last summer a judge cleared it to be put on the market again. Whatever happens at the Pierre, if the princess survives her partner, she is to get $35 million and about $8 million per year, court papers say.  A version of this article appears in print on , on Page A13 of the New York edition with the headline: In Bid to Sell A Duplex, A Princess Is No Help. Order Reprints| Today's Paper|Subscribe
A complaint in Manhattan court suggests a storybook ending is unlikely in the tale of a Jordanian princess, an indisposed financier and a $35 million apartment.