ABSTRACT
Objective: To study the chemical constituents in green walnut husks of Juglans regia. Methods: The chemical constituents were separated and purified by silica gel column chromatography and HPLC. Their structures were determined on the basis of spectroscopic analyses. Results: Fifteen compounds were isolated and the structures were identified as epi-dihydrophaseic acid (1), 4-butoxy-5, 8-dihydroxy-3, 4-dihydronaphthalen-1-one (2), 4-ethoxy-5, 8-dihydroxy-3, 4-dihydronaphthalen-1-one (3), myricatomento-genin (4), nodulisporone (5), 5, 8-dihydroxy-4S-methoxy-β-tethalone (6), 5-hydroxy-4-methoxy-α-naphthalen-1-one (7), isosclerone (8), 4, 5, 8-trihydroxy-1, 2, 3, 4-tetrahydronaphthalene-1-one (9), 1-ethyl malate (10), 1-buthyl malate (11), succinic acid (12), ethyl-O-β-D-glucopyranoside (13), 1α, 2α, 4β-trihydroxy-1, 2, 3, 4-tetrahydronaphthalene (14), and L-2-O-methyl-chiroinosicol (15). Conclusion: Compounds 5 and 10-14 are isolated from the green walnut husks of J. regia for the first time, and compounds 1, 4, and 15 are isolated from this plant for the first time.