The president of a major development firm in South Carolina has filed for bankruptcy protection, the Associated Press reported yesterday. Alan Bruce Kahn filed for chapter 11 protection yesterday noting in court papers that he has fewer than 50 creditors and liability valued between $50 million and $100 million. His assets are estimated between $1 million and $10 million, according to the court papers. Kahn said the financial problems were caused by a drop in property values in recent years.