Flavonoids from the Twigs of the Tibetian Medicine Myricaria germanica

Eleven flavonoids were isolated from the 60% aq.acetone extract of the air-dried twigs of Myricaria germanica(Tamaricaceae),a famous Tibetian medicine.Their structures were elucidated by spectroscopic analysis and identified as 3,5,4′-trihydroxy-7,3′-dimethoxyflavone(1),3,5,4′-trihydroxy-7-methoxyflavone(2),rhamnetin(3),3,5,7-trihydroxy-4′-methoxyflavone(4),tamarixetin(5),kaempferol(6),quercetin-3-O-β-D-glucoside(7),kaempferol-3-O-β-D-glucuronic acid(8),quercetin-3-O-β-D-glucuronicacid(9),quercetrin(10),and afzelin(11),respectively.All compounds were obtained from M.germanica for the first time,and compounds 4,5,7-11 were obtained from the genus Myricaria for the first time.