Chemoselective Hunting Turns Up Natural Products

Chemists have designed an alternative method for selecting and enriching desirable natural products out of the sea of compounds found in crude plant and microbial extracts. Because about half of pharmaceuticals in use today originate from natural products, scientists have great interest in quickly homing in on the most interesting compounds. But traditional enrichment methods involving extraction and chromatographic separation are “still considered a major bottleneck in natural products discovery,” note Indiana University’s Antoinette Y. Odendaal, Darci J. Trader, and Erin E. Carlson in a new report (Chem. Sci., DOI: 10.1039/c0sc00620c). The researchers used silyl-functionalized solid-support resins to immobilize molecules that contain alcohol groups, which allowed the compounds to be plucked out of an extract. The captured molecules were released after the rest of the extract was washed away. The team tested its strategy on anisomycin, a protein biosynthesis inhibitor produced by the bacterium Streptomyces griseolus. The researchers were able to recover 82% of the anisomycin in bacterial extracts. The technique could be generalized to select other functional group classes, the researchers say.