The Henry reactions. A round-bottom flask was charged
with the crude earthworm extract (50 mg), aldehyde (0.50 mmol),
nitroalkane (2.50 mmol), and deionized water (1.00 mL). The
resultant mixture was stirred at 30uC and monitored by TLC.
After a specified reaction time, saturated brine (15 mL) was added
to the reaction, and the mixture was extracted four times with
ethyl acetate (15 mL). The combined extracts were dried over
anhydrous Na2SO4, and the solvents were then removed under
reduced pressure. The residue was purified by silica gel flash
column chromatography (petroleum ether/ethyl acetate) to give
the product.