Sigma-Aldrich Chairman, President and CEO Dr. Jai P. Nagarkatti died of an apparent heart attack on Saturday in St. Louis, Mo., at the age of 63.

Nagarkatti spent his entire career with Sigma-Aldrich beginning in 1976, with his positions spanning R&D, manufacturing, operations, sales and marketing. Nagarkatti was elected president and chief operating officer in 2004, elected to the additional roles of CEO in 2006 and chairman of the board in 2009. He had been a member of the board of directors since 2005.

Speaking on behalf of the board and staff of the company, Barrett Toan, Sigma-Aldrich's presiding director said, "The entire Sigma-Aldrich global organization mourns the loss of Jai and our thoughts and prayers are with his wife, Susan, and his daughter Shanti. Our deepest sympathies go out to them. He was respected by the company's 7,700 employees and will be missed."

Sigma-Aldrich's Board of Directors has had in place a careful succession plan for key officers, including the CEO. Drawing upon over a year of work on a succession plan for senior leadership, the board has elected Rakesh Sachdev as President and CEO. Sachdev most recently served as chief financial officer, chief administrative officer, and senior vice president of the International business. Sachdev was also been elected to the Sigma-Aldrich board of directors on Nov. 14.

The board also has elected Barrett Toan as Chairman as of Nov. 14.