New Triterpenoidal Saponins Acylated with Monoterpenic Acid from Albizia adianthifolia

Four new triterpenoidal saponins acylated with monoterpenic acid, i.e. , adianthifoliosides C, D, E, and F ( 1 – 4 ), besides the two known julibroside III and the monodesmonoterpenyl elliptoside A, were isolated from the roots of Albizia adianthifolia. Their structures were elucidated on the basis of extensive 1D‐ and 2D‐NMR studies and mass spectrometry as 3‐ O ‐{ O ‐ α ‐ L ‐arabinopyranosyl‐(1→2)‐ O ‐ β ‐ d‐ fucopyranosyl‐(1→6)‐ O ‐[ β ‐ d‐ glucopyranosyl‐(1→2)]‐ β ‐ d‐ glucopyranosyl}‐21‐ O ‐{(2 E ,6 S )‐6‐{{4‐ O ‐[(2 E ,6 S )‐2,6‐dimethyl‐6‐( β ‐ D ‐quinovopyranosyloxy)octa‐2,7‐dienoyl]‐ β ‐ d‐ quinovopyranosyl}oxy}‐2‐(hydroxymethyl)‐6‐methylocta‐2,7‐dienoyl}acacic acid 28‐{ O ‐ α ‐ L ‐arabinofuranosyl‐(1→4)‐ O ‐[ β ‐ d‐ glucopyranosyl‐(1→3)]‐ O ‐ α ‐ L ‐rhamnopyranosyl‐(1→2)‐ β ‐ d‐ glucopyranosyl} ester ( 1 ), 21‐ O ‐{(2 E ,6 S )‐6‐{{4‐ O ‐[(2 E ,6 S )‐2,6‐dimethyl‐6‐( β ‐ d‐ quinovopyranosyloxy)octa‐2,7‐dienoyl]‐ β ‐ d‐ quinovopyranosyl}oxy}‐2‐(hydroxymethyl)‐6‐methylocta‐2,7‐dienoyl}‐3‐ O ‐{ O ‐ β ‐ D ‐xylopyranosyl‐(1→2)‐ O ‐ β ‐ d‐ fucopyranosyl‐(1→6)‐2‐(acetylamino)‐2‐deoxy‐ β ‐ d‐ glucopyranosyl}acacic acid 28‐{ O ‐ α ‐ L ‐arabinofuranosyl‐(1→4)‐ O ‐[ β ‐ d‐ glucopyranosyl‐(1→3)]‐ O ‐ α ‐ L ‐rhamnopyranosyl‐(1→2)‐ β ‐ d‐ glucopyranosyl} ester ( 2 ), 21‐ O ‐{(2 E ,6 S )‐6‐{{3‐ O ‐[(2 E ,6 S )‐2,6‐dimethyl‐6‐( β ‐ d‐ quinovopyranosyloxy)octa‐2,7‐dienoyl]‐ β ‐ d‐ quinovopyranosyl}oxy}‐2,6‐dimethylocta‐2,7‐dienoyl}‐3‐ O ‐{ O ‐ β ‐ D ‐xylopyranosyl‐(1→2)‐ O ‐ β ‐ d‐ fucopyranosyl‐(1→6)‐2‐(acetylamino)‐2‐deoxy‐ β ‐ d‐ glucopyranosyl}acacic acid 28‐{ O ‐ α ‐ L ‐arabinofuranosyl‐(1→4)‐ O ‐[ β ‐ d‐ glucopyranosyl‐(1→3)]‐ O ‐ α ‐ L ‐rhamnopyranosyl‐(1→2)‐ β ‐ d‐ glucopyranosyl} ester ( 3 ), and 3‐ O ‐{ O ‐ α ‐ L ‐arabinopyranosyl‐(1→2)‐ O ‐ β ‐ d‐ fucopyranosyl‐(1→6)‐ O ‐[ β ‐ d‐ glucopyranosyl‐(1→2)]‐ β ‐ d‐ glucopyranosyl}‐21‐ O ‐{(2 E ,6 S )‐2,6‐dimethyl‐6‐( β ‐ d‐ quinovopyranosyloxy)octa‐2,7‐dienoyl}acacic acid 28‐{ O ‐ α ‐ L ‐arabinofuranosyl‐(1→4)‐ O ‐[ β ‐ d‐ glucopyranosyl‐(1→3)]‐ O ‐ α ‐ L ‐rhamnopyranosyl‐(1→2)‐ β ‐ d‐ glucopyranosyl} ester ( 4 ).