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L . P . S m t r n o v a , K. I. B o r y a e v , a n d A. I. B a n ' k o v s k i i U D C 547.972From the methanolic mother solntion obtained in the crystallization of acetylpectoltnarin audpectolinarin [1] from Linaria kurd,ca by repeated chromatography on columns of polyamide we have isolated, in addition to pectolinarlgenin and linaroside [2] three other minor components. A chloroform eluate contained the flavone aglycone (I), CleH12Os, mp 258-260°C, tool wt. 284 (mass spectrometry), NMR spectrum: doublet at 7.69 ppm, J = 8 Hz, 2 H (H-2', 6'); doublet at 6.84 ppm, J = 8 Hz; 2 H (H-3', 5'); doublet at 6.41 ppm, J = 2.5 Hz, 1 H (R-6); single, at 6.37 ppm, 1 H (H-3); doublet at 6.07 ppm, J = 2.5 Hz, 1 H (H-8); and singlet at 3.77 ppm, 3 H (CHsO group) [3].The substttuents in positions 5 and 7 are free hydroxy groups (UV spectroscopy). A methoxy group is present in position 4' (the mass spectnun has a fragment with m / e 132). These facts show that (I) is acacetin.A mixture of acacetin with linaroside and then a mixture with a flavone glycoside (II) were eluted by a 5% solution of methanol in chloroform; mp of (II) 237-240°C (decomp.), [~]~ -63.0 ° (pyridine). The acid hydrolysis of (II) formed acacetin and glucose. The carbohydrate component was present in position 7 (UV spectroscopy). The value of the coupling constant of the anomeric proton of the glucose in the NMR spectrum of the trimethylsilyl derivative of (II) (6 Hz) is characteristic for the ~ configuration of the glycosidic bond. The results of the gas-liquid chromatography of the completely methylated carbohydrate component of (II) [4] showed that the glucose is present in the compound in the pyranose form. Consequently, (II) is acacetln 7 -O-~-D-glucopyrano side.On desorption with 50% methanol in chloroform, a flavone glycoside (III), C2BHs~O14 • H~O with mp 260°C (decomp.), [~]~ -90.1 ° (pyridtne) was eluted. Acacetin, glucose, and rhamnose we re found in the products of the acid hydrolysis of (III). The results of UV and NMR spectroscopy permit the assumption that fir[) i s acacetin 7-O-rutinoside (linarin). The results of a comparison with an authentic sample confirmed the identity of these compounds.We have found the same substances in L. kokanica and L. sessilis.

Study of bound water in medicinal preparations has both great practical value and independent theoretical and experimental significance [1]. Various substances, including the quercetin standard, are frequently obtained in the high-purity form by the method of recrystallization from 70% aqueous ethanol. As is known, this procedure may lead to the formation of crystal hydrates whose stability depends on the temperature and water content in the ambient medium [2].Because quercetin standard is used for the certification of drugs and raw plant materials [3,4], it is necessary to know precisely the content of water in the standard preparation. Taking into account that quercetin is dried at a temperature of 105~ prior to the analysis, after which it may be exposed to various temperature and humidity conditions, k was of interest to study the amount and state of water in quercetin depending on the hydrothermal parameters of the surrounding. EXPERIMENTAL PARTThe amount of bound water and the character of its binding in quercetin were determined by thermoanalytical methods, including differential scanning calorimetry (DSC) and thermogravimetry (TG), in combination with potentiometric titration using the Fischer reagent, gravirnetric determination of the weig~ht loss upon drying to constant weig~at in a dry box at 105 + 2.5~ measurement of the sorption isotherms in the static re,me, and study of the dynamics of sorption with time. The sorption of water vapor was studied by exposure of quercetin samples in desiccators above saturated solutions of standard salts [5] capable of creating relative humidity in the air ranging from 2 to 98 %. RESULTS AND DISCUSSIONAs is seen from the data presented in Table I, the initial qucrcetin samples contain about I% water. The therrnoanalyrical curves of this dry sample (Fig. Ib) reveal no thermal effects in the temperature range from -30~ to + 300~ suggesting that water contained in quercetin is subjected to neither freezing nor melting in this interval. These data are indicative of sufficiently strong binding between water molecules and hydrophilic groups of quercetin in the initial sampie. Subsequent scanning in the temperature interval 314-332~ reveals sharp endothcrmal peaks. As is seen from data presented in Table 1, this phase transition has a rather high enthalpy, approaching the energy of bond breaking. These results lead to a conclusion that this temperature interval features the melting of quercetin accompanied by the removal of water. Thus, water contained in the initial quercetin represents a strongly bound crystallization water.Because the initial quercetin samples were obtained by reerystallization, followed by drying in a thermal box at 105~ it was also of interest to study the stability of the crystal hydrate of quercetin under these conditions. As is seen from Table 1, the wei~ht loss of the sample upon drying at 105~ for 3 h amounts to + 0.8%. Study of the dynamics of water vapor sorption by the dried quercetin showed (Fig. 2) 91 Wei~t, %