RESUMO
Objective: To study the flavonoids constituents from the thorns of Gleditsia sinensis and their cytotoxicity against tumor cells. Methods: The compounds were isolated by silica gel, Sephadex LH-20 column chromatography, and HPLC techniques. Their structures were elucidated on the basis of spectroscopic analyses. Results: Twelve flavonoids were obtained and identified as (2R,3R)-5,3',4'-trimethoxyl-7-hydroxyl-flavanonol (1), 5,7,3',4'-tetrahydroxyl-flavanonol (2), 5-methoxyl-3',4',7-trihydroxyl-flavanonol (3), dihydrokaempferol (4), epicatechin (5), 5,7,3',5'-tetrahydroxyl-flavanonol (6), fustin (7), (2R,3R)-7,3',5'-trihydroxyl-flavanonol (8), (2R,3R)-5,7,3'-trihydroxyl-4'-methoxyl-flavanonol (9), quercetin (10), 5,7,4'-trihydroxylflavone-8-C-glucopyranose (11), and 2,7-dimethyl-xanthone (12), respectively. Conclusion: Compound 1 is a new component named G. spina flavanonol A, and compounds 3,8,9, and 12 are isolated from the thorns of G. sinensis for the first time. The results of cytotoxicity test show that the dihydroflavonol compound 7 displays the stronger cytotoxicity against HepG2, A549, and EC109 cell strains, while compounds 1 and 3 have the effects on HepG2 and EC109, and compound 2 has the effect on EC109 cancer cells, respectively.