1. Nucleoside phosphoramidites are purified by column chromatography on silica gel. 2. Purification typically involves extensive column chromatography , extraction to name a few techniques. 3. With a bit of skill, Pasteur pipettes may also be used for microscale column chromatography . 4. With appropriately fine silica gel, the bulb may be squeezed for microscale flash column chromatography . 5. The products are usually extracted and purified by phenol-methylene chloride extraction or by column chromatography . 6. Hydrolysis of the chlorides yield the corresponding alcohols, which are separable by column chromatography over alumina. 7. In fact, the diastereomeric forms of DTHFP have been separated by column chromatography over silica gel. 8. The particle size of the stationary phase is generally finer in flash column chromatography than in gravity column chromatography. 9. The particle size of the stationary phase is generally finer in flash column chromatography than in gravity column chromatography . 10. The final product "'3 "'was isolated by column chromatography at " 30 �C.
