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Graphical abstract Highlights • Eighteen polyamines with phenolic moieties were isolated from the bee pollen of Quercus mongolica. • One putrescine, seven spermidine and one spermine derivative were previously undescribed. • Polyamine derivatives with coumaroyl and caffeoyl moieties showed tyrosinase inhibition. Abstract Eighteen constituents, including nine new compounds, were isolated from the bee pollen of Quercus mongolica. The structures of the new compounds were established on the basis of combined spectroscopic analysis. Structurally, the nine new compounds are polyamine derivatives with phenolic moieties which were assigned as one putrescine derivative, mogolicine A (2), seven spermidine derivatives, mongolidines A-G (3 – 5 , 8 , 12 , 14 , 17) and one spermine derivative, mogoline A (18). Evaluation of the biological activity of isolated compounds revealed that the polyamine derivatives with coumaroyl and caffeoyl moieties showed tyrosinase inhibition with IC 50 values of 19.5–85.8 μM; however, the addition of a methoxy group to phenolic derivatives reduced the inhibitory activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Forty-seven prenylated isoflavonoids were isolated from Masclura tricuspidata leaves. • Sixteen compounds, cudracusisoflavones A-P, were newly reported. • Prenylated isoflavonoids inhibited α-glucosidase activity and AGE formations. • Structure activity relationship was suggested using molecular docking analysis. Investigation of chemical constituents of Masclura tricuspidata leaves resulted in the isolation of 47 isoflavonoids possessing prenyl groups with different numbers and structures. Among them, sixteen compounds named cudracusisoflavones A-P (1 – 16) were first isolated from nature. The isoflavonoids isolated from M. tricuspidata leaves showed anti-diabetic effects as measured by inhibition on α-glucosidase activity and advanced glycation end-products (AGEs) formations. Especially, cudracusisoflavone L (12), a new compound, together with gancaonin M (27), erysenegalensein E (41) and millewanin G (44) showed strong α-glucosidase inhibition with IC 50 values <10.0 μM. In addition, cudracusisoflavones A (1), D (4), M (13) and N (14), together with known prenylated isoflavonoids efficiently inhibited methylglyoxal (MGO)- or glyoxal (GO)-induced AGE formations. Structure activity relationship together with molecular docking analysis suggested the importance of hydroxy group and linear type of prenyl moiety for α-glucosidase inhibition. Conclusively, diverse prenylated isoflavonoids in M. tricuspidata leaves might ameliorate glycotoxicity-induced metabolic diseases. [ABSTRACT FROM AUTHOR]

• Thirty nine xanthones were isolated from the stem of Cudrania tricuspidata. • Nine xanthones, cudracuspixanthones I – Q, were previously undescribed. • These xanthones showed inhibitory effects on pancreatic lipase and fat accumulation. Nine new xanthones, cudracuspixanthones I - Q (12 – 14 , 25 , 32 – 36), and 30 known xanthones (1 – 11 , 15 – 24 , 26 – 31 , 37 – 39) were isolated from the stems of Cudrania tricuspidata (Moraceae). The structures of isolated compounds were established by using 1D and 2D NMR in combination with HR-TOF-MS. Xanthones from the stems of C. tricuspidata exerted pancreatic lipase inhibitory activity. In addition, cudracuspixanthone P (35), a new xanthone, reduced the fat accumulation in liver cells stimulated with fatty acids. Therefore, these compounds might be beneficial in the treatment of metabolic diseases. [ABSTRACT FROM AUTHOR]