Structure of a new chalcone ammothamnidin fromAmmothamnus lehmanni

A new chalcone ammothamnidin with the composition C₂₅H₂₈O₄, mp 112–114°C ] _D ²⁰ + 4.5° (methanol) has been isolated from the epigeal part and roots ofAmmothamnus lehmanni Bge. On the basis of chemical transformations and IR, UV,¹H and¹³C NMR, and mass spectra it has been shown that ammothamnidin has the structure of 2,2,4-trihydroxy-3-(2-isopropenyl-5-methylhex-4-enyl)chalcone.A. Navoi Samarkand State University. Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 445–450, July–August, 1983.