New Chemical Constituents from Borreria verticillata (Rubiaceae)

A phytochemical study on Borreria verticillata has led to the isolation of two novel simple indole alkaloids, 6‐methoxy‐4‐(3‐methylbut‐2‐en‐1‐yl)‐1 H ‐indole, named verticillatine A ( 1 ), and 1‐(1 H ‐indol‐6‐yl)‐3‐methylbutan‐1‐one, named verticillatine B ( 2 ), one new iridoid, 6′‐ O ‐(2‐glyceryl)scandoside methyl ester ( 3 ), with the glycerol unit linked to a glucose unit, and two known ones, asperuloside ( 4 ) and scandoside methyl ester ( 5 ). The structures of these compounds were elucidated on the basis of spectroscopic‐data analyses, mainly 1 H‐ and 13 C‐NMR, including 2D experiments ( 1 H, 1 H‐COSY, NOESY, HMBC, and HMQC), and HR‐ESI‐MS.