V.I. Sheichenko, O.P. Sheichenko, O.N. Tolkachev, L.D. Shipulina, V.A. Bykov

Seabuckthorn (Hippophae rhamnoides L.) leaves are rich of polyphenols (hydrolizing gallo-ellagi-tannins and flavonoids). There was elaborated a new antiviral phytodrug Hiporamin at the basis of the tannin fraction. The drug possesses a wide spectrum of antiviral activity in respect of pathogenic viruses of human beings and animals. The quantitative UV-spectrophotometric method of tannin determination in the polyphenol fraction from Seabuckthorn leaves was earlier worked out. There was found out, that the 1H NMR method may be also applicable for the quantitative content determination of the total and individual tannins in extracts of Seabuckthorn leaves, in polyphenol fraction, while signals of aromatic protons of galloyl, hexahydroxydiphenoyl and valenoyl fragments were used for evaluation. As a result signals of strictinin, isostrictinin, casuarinin, casuarictin and pedunculagin were identified in the 1H NMR spectrum of the total tannins shown at fig. 1. Signal of protons of unsubstituted gallic acid (artifact in the technological processes) was absent in the spectra of analyzed samples. There was proposed an equation for the tannin contents calculation using integral intensity signals in the region of aromatic and carbohydrate protons. Results produced are concurrent with the data of the UV-spectrophotometric determination. Comparative analytical data are given in the table. The computer 3D molecular model of the basic tannin casuarinin was calculated.