numbers of fibroblasts and collagen, portal edema, anisokaryosis of hepatocyte nuclei with some cytomegaly, and bile duct proliferation. History The first reported isolation of ‘Riddelliine’ was done by Richard H. F. Manske, a chemist at the National Research Laboratories in Ottawa, Ontario, Canada. This was handed in on the 13th December 1938 and published in the 17th volume, section B in the Canadian Journal of Research, January 1939. The formula was confirmed and a structure was added by Roger Adams, K.E. Hamlin, JR., C.F. Jelinek and R.F. Phillips in the Journal of the American Chemical Society 1942. See also Pyrrolizidine alkaloid, the large class of molecules containing riddelliine Senecionine, a closely related pyrrolizidine alkaloid References Pyrrolizidine alkaloids IARC Group 2B carcinogens Alkene derivatives Diols Lactones