3-(p-Methoxyphenyl)-1,2,3,4-tetrahydronaphthalen-1-one is an intermediate in synthesizing Flocoumafen-d4 (F401502), an isotope labelled Flocoumafen is a second generation anticoagulant rodenticide. Flocoumafen is extremely effective against strains of pest rodents resistant to conventional anticoagulants. Flocoumafen is highly toxic and is used strictly in sewers and indoors in some places such as UK.