Arden Group, the Compton-based parent of Mayfair markets, said it is negotiating with a number of prospective buyers for the sale of 17 supermarkets and a distribution center in Arizona . . . Diamond Shamrock officials cut the annual cash dividend to 40 cents per share from $1 and authorized the repurchase of up to 25 million shares of its common stock over the next two years . . . Moody's, which in April said it would review Carter Hawley Hale's senior long-term debt for possible downgrading, confirmed the BAA3 rating, noting that the proposed sale of Wanamaker's should improve profitability.