Aristolochia reticulata

C15H20O2, Mr 232.32, colorless cryst., mp. 110-111 °C, [a]p +145.8° (CHCI3) soluble in chloroform, ethanol, and THE. An a,j3-unsaturated sesquiterpene lactone with the germacrene skeleton (see ger-macrenes) from Aristolochia reticulata and A. serpen-taria. The absolute configuration has been determined both by X-ray diffraction and enantiospecific synthesis. ... 

The Aristolochias are used in medicine as tonics due to the presence of bitter principles, though Hesse suggested that A. reticulata Nutt, then the serpentary root of commerce, might contain aristolochine, and the view that the bitter constituents are of alkaloidal character has been confirmed by Krishnaswamy, Manjunath and Rao, for A. indica L. 

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