The crude earthworm extract catalysed Biginelli reactionsa.

aOptimized reaction conditions: aldehyde (0.50 mmol), urea (1.00 mmol), acetoacetate (1.00 mmol), deionized water (0.30 mL), n-butyl acetate (0.70 mL) and the crude earthworm extract (75 mg) at 45°C.bYield of isolated product after silica gel chromatography.cDetermined by chiral HPLC analysis performed using Chiralpak AD-H column, by comparing the retention time with those of known compounds (For details, please see the Supplementary material).dThe absolute configuration was not determined.eUn-optimized conditions: benzaldehyde (0.50 mmol), urea (1.00 mmol), ethyl acetoacetate (1.50 mmol), deionized water (0.05 mL), n-butyl acetate (0.95 mL) and the crude earthworm extract (100 mg) at 45°C.fThe reaction was carried out in the absence of the crude earthworm extract, otherwise under the same conditions as entry 8.