Quercetin-d3 hydrate, a deuterated form of Quercetin hydrate, acts as a flavonoid that stimulates recombinant SIRT1 and serves as a PI3K inhibitor. The compound specifically exhibits IC50 values of 2.4 µM, 3.0 µM, and 5.4 µM against PI3Kgamma, PI3Kdelta, and PI3Kbeta, respectively.