Acylated sucroses and acylated quinic acids analogs from the flower buds of Prunus mume and their inhibitory effect on melanogenesis

Five acylated sucroses, mumeoses A–E, and three acylated quinic acid analogs were isolated from flower buds of Prunus mume cultivated in Zhejiang Province, China, together with 13 known compounds. The obtained acylated quinic acid analogs significantly inhibited melanogenesis without inducing cytotoxicity. •Acylated sucroses and acylated quinic acids were isolated from flower buds of Prunus mume, and their chemical structures were elucidated.•Acylated quinic acid analogs significantly inhibited melanogenesis without inducing cytotoxicity.•Inhibitory effects of acylated quinic acid analogs were stronger than that of arbutin.•Acylated quinic acid analogs are promising therapeutic agents for the treatment of skin disorders. The methanolic extract from the flower buds of Prunus mume, cultivated in Zhejiang Province, China, showed an inhibitory effect on melanogenesis in theophylline-stimulated B16 melanoma 4A5 cells. From the methanolic extract, five acylated sucroses, mumeoses A–E, and three acylated quinic acid analogs, 5-O-(E)-p-coumaroylquinic acid ethyl ester, and mumeic acid-A and its methyl ester, were isolated together with 13 known compounds. The chemical structures of the compounds were elucidated on the basis of chemical and physicochemical evidence. Inhibitory effects of the isolated compounds on melanogenesis in theophylline-stimulated B16 melanoma 4A5 cells were also investigated. Acylated quinic acid analogs substantially inhibited melanogenesis. In particular, 5-O-(E)-feruloylquinic acid methyl ester exhibited a potent inhibitory effect [inhibition (%): 21.5±1.0 (P