L-Aspartic acid, N-[4-[[(2,4-diamino-5-chloro-6-quinazolinyl)methyl]amino]benzoyl]-

Chlorasquin inhibits thymidylate synthetase with an approximate Ki value of 4.9 μM. Chlorasquin is also a folate antagonist, testing the Methotrexate (HY-14519) effect. Chlorasquin binds tighter to dihydrofolate reductase at alkaline pH than does Methotrexate, which is promising for research of antipsoriatic agents[1][2].

[1] Chello PL, et al. Elevation of dihydrofolate reductase, thymidylate synthetase, and thymidine kinase in cultured mammalian cells after exposure to folate antagonists. Cancer Res. 1976 Jul;36(7 PT 1):2442-9. PMID:1277151
[2] Hynes J B, et al. Quinazolines as inhibitors of dihydrofolate reductase. 4. Classical analogs of folic and isofolic acids[J]. Journal of Medicinal Chemistry, 1977, 20(4): 588-591. DOI:10.1021/jm00214a030