Fibrosis of the liver is a chronic inflammatory process with activation of hepatic stellate cells and abnormal accumulation of proteins in the extracellular matrix. However, it is known that pyrimidine derivatives have a beneficial effect on the condition of various organs with the ongoing process of fibrosis. Therefore, the aim of this work was to investigate the effect of the drug Xymedon (1,2-dihydro-4,6-dimethyl-1-N-(2-hydroxyethyl)pyrimidine-2-one, (compound 1) and its conjugate with L-ascorbic acid (compound 2) on collagen remodeling in rat liver tissue. For this purpose, female Wistar rats were used to model fibrosis by oral administration of carbon tetrachloride (CCl4) and ethanol for 8 weeks. Then the rats were treated with the studied compounds for 2 or 4 weeks. Histological analysis by hematoxylin-eosin and Van Gizon’s staining of liver slices, biochemical analysis of blood serum and Western blot analysis of COX-2 level in rat liver homogenates were performed. It has been shown that in the control group without treatment, after 2 weeks of withdrawal of CCl4 + ethanol, collagen remodeling occurs to the certain chronic level. At the same time, compound 2 reduces the level of collagen fibers by 41% compared to the control group, while native compound 1 has no such effect. Also, in all groups studied, there was the decrease in the inflammatory marker COX-2 both after 2 weeks of CCl4 + ethanol withdrawal and after treatment with studied compounds 1 and 2. Thus, compound 2 (conjugate of Xymedon with L-ascorbic acid) has the greater antifibrotic effect on the rat liver fibrosis model compared to the native molecule of compound 1 (Xymedon). At the same time, this effect is not associated with the level of COX-2.