反应详情

Guanosine triphosphate (GTP) (300 mg, 0.5 mmol) was methylated using dimethyl sulfate according to the procedure of Hendler et al. ((1970) Biochemistry 9, 414) with modification. The reaction mixture was neutralized and the product purified on a DEAE Sephadex A-25 (Sephadex is a registered trademark of Pharmacia Fine Chemicals, Inc.) column (3×50 cm). The column was washed with water and then eluted with a linear gradient of 0 to 0.8M triethylammonium bicarbonate (TEAB), pH 7.8 (2 l total volume). Twenty-milliliter fractions were collected and assayed spectrophometrically at 260 nm. m7GTP eluted at approximately 0.4M, and the peak was pooled and repeatedly evaporated to dryness from water vacuo. m7GTP-triethylammonium salt was obtained as a white solid (0.25 mmol, 50% yield).

1. customthe product purified on a DEAE Sephadex A-25 (Sephadex
2. washThe column was washed with water
3. washeluted with a linear gradient of 0 to 0.8M triethylammonium bicarbonate (TEAB), pH 7.8 (2 l total volume)
4. customTwenty-milliliter fractions were collected
5. washm7GTP eluted at approximately 0.4M
6. customrepeatedly evaporated to dryness from water vacuo