Analog of antimalarial hydroxynaphthoquinones; t-butyl deriv of parvaquone, q.v. Prepn: A. T. Hudson, A. W. Randall, EP 77550; eidem, US 4485117 (1983, 1984 both to Wellcome). In vivo and in vitro antiprotozoal activity: A. T. Hudson et al., Parasitology 90, 45 (1985); N. McHardy et al., Res. Vet. Sci. 39, 29 (1985). Treatment of bovine theileriosis: S. Dhar et al., Vet. Rec. 119, 635 (1986). Efficacy as a chemoimmunoprophylactic of theileriosis: eidem, ibid. 120, 375 (1987).