STUDIES ON NAPHTHOIC ACID ESTERS FROM THE ROOTS OF RUBIA CORDIFOLIA L.

Four naphthoic acid esters including a new compound were isolatedfrom the roots of Rubia cordifolia L.. The new one was named as rubilactone and its struc-ture was elucidated as 3'-carbomethoxy-4'-hydroxy-naphtho1',2'-2,3 pyran-6-one(I) based on the physicochemical properties and spectrometric analyses (UV, IR, MS,¹HNMR and ¹³CNMR). The other three were 3'-carbomethoxy-4'-hydroxy-naphtho 1',2'-2, 3 furan (Ⅱ), dihydromollugin (Ⅲ) and 3-carbomethoxy-2-(3'-hydroxy)isopentyl-1,4-naphthohydroquinone- 1- O-β- D-glucoside(Ⅳ).