Sodium Hydroxide → 5-Deazaaminopterin

Participants

Reaction Steps

A solution of the product obtained in Example 2, VII (R1 =C2H5) (359 mg, 0.724 mmol) in dimethyl sulfoxide (10 ml) under N2 was treated with 1 N NaOH (1.81 ml, 1.81 mmol), stirred in a stoppered flask under N2 for 6 hours, and evaporated to dryness in vacuo at <30° C. A solution of the residue in water (18 ml) was filtered and acidified to pH 3.6 with 1 N HCl. The precipitate was collected by filtration, washed with water at pH 3.6 and dried in vacuo (P2O5); yield 297 mg (87%), mp indefinite (softens above 200° C.); mass spectrum, m/e 440 (M+1)+ ; λmax nm (ε×10-3): 0.1 N HCl --218 (40.5), 280 sh (16.9), 300 (18.8); pH 7--218 (38.5), 2.45 (19.2), 280 (23.9), 296 sh (22.7); 0.1 N NaOH --248 (22.0), 280 (24.4), 296 sh (22.7), 345 (7.75); 1H-NMR (DMSO-d6, 6% w/v), δ2.00 m (CH2CH2CO), 2.29 t (CH2CO), 4.36 m (CHN, CH2N), 6.66 d, 7.68 d (C6H4), 7.41 (NH2), 8.04 m (NH2, NH, CO2H), 8.52 d, 8.70 d (5 --CH, 7 --CH).

Provenance & Evidence