Document 82wrGwL49MzYrwD87jzVxLgvZ

(4/13/56) ETHYL CORPORATION Research Laboratories . 1600 West Eight Mile Road Ferndale 20, Detroit, Michigan April 12, 1956 Dr.F. F. Heyroth College of Medicine University of Cincinnati Eden Avenue Cincinnati 19, Ohio Dear Dr. Heyroth: I should like to inquire whether you have had a chance to do any work with our APR-12S, methyl cyclopentadienyl manganese tricarbonyl. According to our records, if I am correct, you have given us a preliminary opinion regarding the toxicity of the related compound, APR-122, the parent methyl cyclopentadienyl manganese tricarbonyl, but we have heard nothing from you regarding the APR-123 since sending you a sample on April 27, 1955. Perhaps you have sent us a letter on this compound and I have missed it in perusing our files. Sincerely yours, /s/ Hymin Shapiro Hymin Shapiro Research Planning Coordinator Chemical Research Division HS/jtd KE 001S297