The invention relates to application of B-ring ethyoxyl
flavanonol in preparing medicaments for treating
hepatitis B viruses, in particular to application of a compound as shown in a formula (1) or a medicinal salt thereof in preparing medicaments for clearing away
hepatitis B
virus surface antigens (
HBsAg) and
hepatitis B e-
antigen (
HBeAg) and medicaments for inhibiting the duplication of
hepatitis B virus desoxyribonucleic acid (HBV
DNA). The compound or the medicinal salt thereof has extremely obvious activity on inhibiting the
HBsAg and the
HBeAg, and in the presence of a concentration of 20
microgram / milliliter, the intensities for clearing away the
HBsAg and the
HBeAg of the compound or the medicinal salt thereof are respectively 99.8 percent and 48.5 percent and are 6.2 times and 2.7 times of that of alpha-
interferon which is a
positive control medicament. More importantly, in the presence of the concentration, the inhibition ratio of the compound or the medicinal salt thereof to the HBV
DNA is 64.7 percent, and the activity is 1.7 times of that of the alpha-
interferon. Accordingly, the flavone
lignan or the medicinal salt thereof can be expected to be used for preparing non-
nucleoside medicaments for treating infectious diseases of the
hepatitis B viruses.