Prepn: Tomcufcik, DE 1933112 (1970 to Am. Cyanamid), C.A. 72, 90113c (1970). Activity studies: Kantor et al., Science 168, 373 (1970); Wong et al., Biochem. Biophys. Res. Commun. 46, 621 (1972). Metabolism: Zulalian et al., 163rd Am. Chem. Soc. Meeting (Boston, April 1972) Abstracts of Papers, PEST 12, 13. Animal studies: Millard, Res. Vet. Sci. 11, 394 (1970); Joyner, Norton, ibid. 13, 279 (1972).