Any compound that has two phosphonate groups(noun)
Bisphosphonate(noun)
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Use "biphosphonate" in a sentence
"Unfortunately, I do not have a copy of the complaint, but I do know that when the study was published, a journalist dug up the information that a couple of the researchers had some connections to biphosphonate manufacturers."
"Alberts S, Hallum AV, Stratton-Custis M, Garcia D J, Gleason-Guzman M, et al. (2001) Phase I pharmacokinetic trial and correlative in vitro phase II tumor kinetic study of apomine (SR-45023A), a novel oral biphosphonate anticancer drug."