A. Gangjee et al. / Bioorg. Med. Chem. 14 (2006) 8590–8598
8597
C19H19N5O6ÆH2OÆ0.2CH3OH: C, 52.67; H, 5.02; N,
16.00. Found: C, 52.84; H, 4.77; N, 15.64.
CA 10914 (R.L.K.), and Roswell Park Cancer Institute
Core Grant CA16065 from the NCI. The authors thank
Mr. William Haile for performing growth inhibition
studies and FPGS activity assays.
6.2.1. Drug preparation. Drug solutions were standard-
ized using extinction coefficients. Extinction coefficients
were determined for 13 (pH 1, kmax 227 nm (22,900); pH
7, kmax 255 nm (19,200); pH 13, kmax 248 nm (19,300))
and for 14 (pH 1, kmaxꢀ1 248 nm (20,300), kmaxꢀ2
301 nm (7,900); pH 7, kmax 247 nm (20,400); pH 13, kmax
248 nm (20,200)) and the extinction coefficients for meth-
otrexate (MTX), a gift of Immunex (Seattle, WA), were
from the literature.30 Aminopterin was purchased from
Sigma Chemical Co. (St. Louis, MO). Other chemicals
and reagents were of reagent grade or higher.
References and notes
1. Presented in part in the 12th International Symposium on
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for Mycoplasma contamination (Mycoplasma Plus PCR
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MTX-resistant sublines R1,27 R2,28 and R30dm29 were
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R30dm expresses 1% of the folylpolyglutamate synthe-
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[3H]glutamate, instead of the standard 4 mM. The result-
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Acknowledgments
This work was supported, in part, by CA 89300 (A.G.),
AI 44661 (A.G.), CA 43500 (J.J.M.), CA 16056 (J.J.M.),
26. Gangjee, A.; Mavandadi, F.; Queener, S. F. J. Med.
Chem. 1997, 40, 1173.