Cycloguanil hydrochloride (Standard) is the analytical standard of Cycloguanil hydrochloride (HY-12784A). This product is intended for research and analytical applications. Cycloguanil hydrochloride is a dihydrofolate reductase (DHFR) inhibitor with an IC50 of 10.8 µM against human DHFR. Cycloguanil hydrochloride blocks the folate metabolic pathway, thereby affecting nucleotide synthesis and interfering with DNA replication. Cycloguanil hydrochloride inhibits DHFR in Plasmodium and is thus used in malaria research. Cycloguanil hydrochloride also potently inhibits DHFR in human cancer cells and blocks the transcriptional activity of STAT3, thereby exhibiting anticancer activity[1][2].