Ribocil-C Racemate is the racemate of Ribocil-C, a highly selective inhibitor of bacterial riboflavin riboswitches that control the expression of de novo riboflavin (RF, vitamin B2) biosynthesis in Escherichia coli.

Ribocil-C, a highly selective inhibitor of the flavin mononucleotide (FMN) riboswitch, effectively regulates the expression of de novo riboflavin (RF, vitamin B2) biosynthesis in Escherichia coli. It specifically targets dual FMN riboswitches to control both RF biosynthesis and uptake processes, critical for the growth and pathogenesis of Staphylococcus aureus. Additionally, Ribocil-C, a small-molecule synthetic FMN analog, binds the FMN riboswitch in various Gram-negative bacteria, including Escherichia coli, Pseudomonas aeruginosa, and Acinetobacter baumannii. By inhibiting ribB expression and RF synthesis, it successfully halts bacterial proliferation [1] [2].

Treatment with higher doses of Ribocil-C (60 and 120 mg/kg) demonstrated a dose-dependent decrease in bacterial load, with reductions of 1.87 and 3.29 log10 [CFU per g spleen], respectively, compared to the sham-treated mice. No mortality or significant toxicity effects were observed [2].