EXHIBIT 2.2 CONFORMED COPY AMENDMENT TO PURCHASE AGREEMENT AMENDMENT (the "Amendment"), dated as of October 1, 2001, to the Purchase Agreement, dated as of June 7, 2001 (the "Purchase Agreement") by and among E.I. du Pont de Nemours and Company, a...Purchase Agreement • October 12th, 2001 • Bristol Myers Squibb Co • Pharmaceutical preparations
