SR-BI (scavenger receptor class B type I) mediates cellular selective uptake of cholesteryl esters from high-density lipoprotein (HDL)'s core.  Small molecule probes of the selective lipid uptake pathway are of interest to elucidate the mechanism of lipid metabolism in hepatic and other tissues.  Previous high throughput chemical screens using intact cells have identified five compounds (BLT 1-5) that inhibited SR-BI-dependent lipid transport.  Of the five BLT compounds, BLT-1 is the most potent (HDL uptake inhibition) with an IC50 of 15nM (cell-based radioactive binding assay).  BLT-1 binds SR-BI directly in a membrane lipid environment (liposome-based binding assay). Nieland et al., Biochemistry, 47, 460-472, 2007.  

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