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The known compounds cappariloside A and stachydrin, an adenosine nucleoside, and for the first time from plants of the Capparidaceae family the known compounds hypoxanthine and uracil were isolated from Capparis spinosa (Capparidaceae) fruit.Capparis spinosa (Capparidaceae) is widely distributed throughout the whole world. Information on alkaloids, flavonoids, and glycosides [1][2][3][4][5] in addition to lipids and carbohydrates [6] from this plant has been published.Herein we report a study of alkaloids from fruit of C. spinosa growing in Xinjiang Autonomy Region of China. The alcohol extract of ground and defatted ripe fruit of C. spinosa produced total extracted substances containing also water-soluble alkaloids of the betaine type. The lipophilic components were removed by washing the acidic solution of extracted substances with ether. The total alkaloids were obtained by treatment of the acidic solution with conc. ammonia to adjust the pH to 9 and extraction with n-butanol (fraction A). The dried alkaloidal fraction A was chromatographed over a silica-gel column with elution by CHCl 3 , CHCl 3 :CH 3 OH, and CH 3 OH. Work up with CH 3 OH of the CHCl 3 :CH 3 OH (12:1) fractions isolated amorphous hypoxanthine (1) and uracil (2) [7,8], which were identified using PMR and 13 C NMR spectral data and authentic samples (spectral properties are given in Experimental).Crystalline 3, mp 228-229°C, was isolated from CHCl 3 :CH 3 OH (10:1) fractions. The UV spectrum of 3 had absorption maxima at 206.4 and 259.6 nm. The IR spectrum had absorption bands for active H at 3425, 3370 (NH 2 ), 3320, and 3143 (OH) cm −1 ; lactone ring (tetrahydrofuran), 1680; ether, 1100 and 1030; and tri-and disubstituted aromatic rings, 1600, 1577, 870, 822, 795, and 765. The mass spectrum of 3 gave a peak for the molecular ion with m/z 267 and fragments with m/z 148 and 119 produced by cleavage of the tetrahydrofuran ring. Peaks for ions with m/z 134 and 133 corresponded to fragments formed by cleavage of the C-N bond between the main part of the molecule and the tetrahydrofuran ring. NMR data ( 1 H and 13 C) are given in Experimental.The spectral data (UV, IR, mass, NMR) were reminiscent of those of adenosine (3) [9]. However, the lack of an authentic sample prohibited reliable identification of 3 as adenosine. As a result, a single-crystal x-ray structure analysis (XSA) of 3 showed that the isolated base was in fact the known nucleoside adenosine (C 10 H 13 N 5 O 4 ), which is constructed from D-ribose and a purine base in which the N-9 atom of the purine base adenine is bonded to C-1 of D-ribose [10][11][12][13]. Adenosine

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The isolation of the alkaloids codonopsine (1) and codonopsinine (2) from the aerial part of Codonopsis clematidea (harebell, Campanulaceae) has been previously reported [1]. Based on spectral data (IR, UV, NMR, and mass spectroscopy) and chemical transformations (Hofmann degradation, KMnO 4 and periodic-acid oxidation), the structures for 1 and 2 were established as 1,2-dimethyl-3,4-dihydroxy-5-(3,4-dimethoxyphenyl)pyrrolidine and 1,2-dimethyl-3,4-dihydroxy-5-(4methoxyphenyl)pyrrolidine, respectively [2, 3]. Later double-resonance PMR spectroscopy was used in an attempt to determine the relative configuration of the substituents on the N-methylpyrrolidine ring [4].The methyl iodide of codonopsine (3) was prepared and its x-ray crystal structure was solved in order to solve unambiguously these issues.The results of the x-ray structure analysis (XSA) confirm the proposed chemical formulas for 1 and 2 [2, 3] but necessitate a correction in the stereochemistry of the N-methylpyrrolidine ring. Figure 1 shows the corrected structural formulas for 1 and 2 and the molecular structure of codonopsine methyl iodide (3).It can be seen that the C2 methyl and the C4 hydroxyl have the α-configuration; the C3 hydroxyl and the C5 substituted aromatic ring, the β-configuration. The N-methylpyrrolidine ring adopts the 5α-envelope conformation. Atom C5 deviates from the plane of the other four atoms (coplanar within ±0.027 Å) by 0.625 Å. For this reason, only C4 and C5 can have substituents that are pseudo-axial or -equatorial relative to the plane of the four atoms. The C4 hydroxyl and C5 aromatic ring are pseudo-equatorial. The planar (±0.01 Å) substituted aromatic ring is twisted relative to the plane of the pyrrolidine ring by 74.2°.The absolute configuration of 3 was also established from the XSA. According to the Flack parameter [5] [0.00(4)], the absolute configuration of the chiral centers corresponds with that shown in Fig. 1. Therefore, all asymmetric centers (C2, C3, C4, and C5) have the R-configuration.

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747.945+547.79+548.737 G. Genzhemuratova, M. G. Levkovich, and Kh. M. ShakhidoyatovN-Acyl cytisine derivatives were synthesized by acylation with acetic anhydride; benzoyl and o-bromo-and p-nitrobenzoyl chlorides; and crotonyl and cinnamoyl chlorides. The structures of the synthesized compounds were studied using IR, PMR, and x-ray structure analysis (XSA). PMR spectra of the N-acylcytisines in solution typically had two rotational isomers around the N12-CO bond. Conformational analysis was performed using XSA for the position of the acyl group relative to the cytisine core. Bond lengths and angles of the acyl groups involved in the conjugation were analyzed.The broad spectrum of biological activity of cytisine (1) and its derivatives [1, 2] makes them a promising class for practical application. On the other hand, the chiral 3,7-diazobicyclo[3.3.1]nonane skeleton is interesting for studying structural features of substituted cytisines [3][4][5][6]. Until now, a large number of cytisine derivatives with various groups on the N atom have been synthesized [7][8][9][10][11][12], including acryloyl groups [13], thiazoles, benzthiazoles [11], and 1,2,4-thiadiazole groups [12]. In continuation of our research on transformations of 1 [11,12] and in order to find biologically active compounds in this series, we synthesized acyl derivatives via acylation of 1 with acetic anhydride and acid chlorides. The acylating agents were acetic anhydride; benzoyl-and o-bromo-and p-nitrobenzoyl chlorides; and crotonyl and cinnamoyl chlorides. The reaction with acetic anhydride occurred with an excess of it. Acylation by the acid chlorides occurred in anhydrous toluene under reflux: R = -ÑH 3 (2); -Ñ 6 H 5 (3); -Ñ 6 H 4 -Br-o (4); -C 6 H 4 -NO 2 -n (5); -CH=CH-C 6 H 5 (6); -CH=CH-CH 3 (7) Acylation of 1 by acid chlorides was carried out without a HCl acceptor. Atom N12 of ring C played this role. Structures of 2-7 were confirmed by IR and PMR spectra and by an x-ray structure analysis (XSA) for N-o-bromobenzoylcytisine (4), N-p-nitrobenzoylcytisine (5), and N-crotonylcytisine (6).IR spectra contained absorption bands at 1643-1653 cm -1 (ν CO ) and 1634-1647 (ν CO ). The physicochemical properties of 2, 3, and 7 agreed with those published. PMR spectra of the N-acylcytisines in solution characteristically showed several rotational isomers around the N12-CO and CO-R bonds. They could produce spectra of several conformers or simply give very broad spectral lines because the barriers to rotation were small. In several instances resonances could not be unambiguously assigned.