THE STRUCTURES OF FOUR MINOR DITERPENEQUINONES PRZEWAQUINONES C.D.E.AND F.FROM THE ROOT OF SALVIA PRZEWALSKII MAXIM VAR.MANDARINORUM (DIELS) STIB.

Four new diterpenequinones named przewaquinone C. C₁₈H₁₆O₄, przewaquinone D. C₁₈H₁₆O₅, przewaquinone E. C₁₈H₁₆O₅ and przewaquinone F. C H O, were isolated from the root of Salvia przewalskii Maxim. var. mandarinorum (Diels) Stib. by chromatographic method.By means of spectral and chemical evidences structures of przewaquinone C. D. E. and F. were elucidated as formulas (Ⅰ), (Ⅱ), (Ⅲ), and (Ⅳ).