Table 2. Inhibitory Concentrations (IC50, μM) of DHFR and TS.
Compd | TS Inhibitory Activitya | DHFR Inhibitory Activitya | ||||
---|---|---|---|---|---|---|
IC50 Values (μM) of Thymidylate Synthase Inhibition | IC50 Values (μM) of Dihydrofolate Reductase Inhibition | |||||
Humanc | E. colic | Toxoplasma gondiid | Humane | E. colif | Toxoplasma gondiid | |
1 | 0.54 | > 27 | 0.11 | > 33 (17)b | > 33 (35) | 33 |
2 | 0.39 | > 26 | > 26 | > 31 (7) | > 31 (27) | > 31 (22) |
Pemetrexed g | 29.0 | 15 | 14 | |||
Raltitrexed h | 0.29 | 2.3 | 0.48 | |||
MTX | 0.022 | 0.0066 | 0.019 | |||
Trimethoprim | 680 | 0.02 | 2.9 |
The percent inhibition was determined at a minimum of four inhibitor concentrations within 20% of the 50% point. The standard deviations for determination of 50% points were within ± 10% of the value given.
Numbers in parentheses indicate the percent inhibition at the stated concentration.
Kindly provided by Dr. Frank Maley, New York State Department of Health.
Kindly provided by Dr. Karen Anderson, Yale University, New Haven, CT.
Kindly provided by Dr. Andre Rosowsky, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA.
Kindly provided by Dr. R. L. Blakley, St. Jude Children's Hospital, Memphis, TN.
Kindly provided by Dr. Chuan Shih, Eli Lilly and Co.
Kindly provided by Dr. Ann Jackman, CRC Centre for Cancer Therapeutics, Surrey SM2 5NG, England.