Ethynylcytidine is a nucleoside analog and a highly potent inhibitor of RNA synthesis, exerting inhibitory effects on RNA polymerases I, II and III. It exhibits significant anti-tumor activity in a variety of cancer models and also serves as an important click chemistry reagent; its molecular structure contains an alkyne group, which can undergo copper-catalyzed azide-alkyne cycloaddition (CuAAC) with azide-modified molecules.

After exposure of five human tumor cell lines to Ethynylcytidine for 4 h, 24 h and 72 h, the half-maximal inhibitory concentration (IC₅₀) values were 0.114~1.032 μM, 0.015~0.067 μM and 0.008~0.058 μM [1].

In the OCUM-2MD3 and LX-1 xenograft models, Ethynylcytidine induced tumor regression at the minimally toxic dose, exhibiting highly potent anti-tumor activity. the tumor growth inhibition rate (IR) of this compound reached 90% or higher on the 15th day of the experiment under all three administration regimens. Among them, a single weekly administration at a dose of 6 mg/kg showed an especially prominent anti-tumor effect, with the inhibition rate against LX-1 tumors reaching as high as 98% and achieving significant tumor regression. Although administration three or five times a week also exerted a strong anti-tumor effect with an inhibition rate of approximately 85%, an insufficient dose for single weekly administration led to a drop in the inhibition rate to below 60%, resulting in a significant attenuation of anti-tumor activity [1].

DMSO: 200 mg/mL (748.39 mM), Sonication is recommended.

Saline: 2.5 mg/mL (9.35 mM), Sonication is recommended.

10% DMSO+40% PEG300+5% Tween-80+45% Saline: 3.3 mg/mL (12.35 mM), Sonication is recommended.