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was demonstrated by spectral methods and X-ray diffraction structural analysis.Keywords: 5-aryl-3-(-thiomorpholinoethyl)-1,2,4-oxadiazoles, 2-amino-8-thia-1-aza-5-azoniaspiro-[4.5]dec-1-ene chloride hydrate, substituted benzoic acids, acid hydrolysis, X-ray diffraction structural analysis.The possibility that -amino-O-aroylpropioamidoximes and 3-(-aminoethyl)-5-aryl-1,2,4-oxadiazoles exist both as stable bases and hydrochlorides has been demonstrated in our previous work, in which -piperidine, -morpholine, and -benzimidazole derivatives are described. These compounds do not undergo structural change upon isolation from the reaction mixture and recrystallization. Physicochemical and spectral data as well as X-ray diffraction structural data were obtained for these compounds [1][2][3]. Scheme 1 N NH 2 N OH N S O C 6 H 4 X NH 2 N O N O N C 6 H 4 X N XC 6 H 4 COCl N NH 2 N OH S S S -H 2 O 3 2a-e 1a-e 3·2HCl 2HCl HCl · 1,2 a X = p-MeO, b X = p-Me, c X = H, d X = p-Br, e X = m-Cl

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UDC 547.044/046Berberine, isocorydine, glaucine, thalicmidine, aromoline, oxyacanthine, and the new 1-benzylisoquinoline alkaloid turcomanine have been isolated from Berberis turcomanica Kar. The structure of the new alkaloid has been established on the basis of chemical transformations and spectral characteristics. This is the first time that isocorydine, thalicmidine, arornoline, and oxyacanthine have been isolated from this plant.Continuing an investigation of Berberis turcomanica Kar. [1-3], we have studied the alkaloid composition of the leaves of this plant gathered in the incipient fruit-bearing stage in the region of Kara-Kala.Chloroform extraction yielded 0.17% of bases, by the separation of which on a silica gel column seven alkaloids, including one new one (1), were isolated. Berberine and glaucine have been isolated previously but this is the f'trst time that oxyacanthine, aromoline, isocorydine, and thalicmidine have been isolated from this plant. All the known bases were identified by their spectral characteristics and by direct comparison with authentic specimens.Compound (1) was an optically inactive phenolic base forming a hydrobromide sparingly soluble in the majority of organic solvents.The UV spectrttm of (1) was close to that of papaverine [4]. Its IR spectrum contained absorption bands of active hydrogen in the 3380-2750 cm -1 region, corresponding to the stretching vibrations of free and associated OH groups. In the mass spectrum the strongest peaks were those of the M + and [-M -1] + ions which showed the aromatic nature of the alkaloid.When (1) was acetylated with acetic anhydride in pyridine the triacetyl derivative (2) was obtained. The mass spectrum of (2) contained the peak of the molecular ion with m/z 423 and the peaks of ions with m/z 381, 339, 297, corresponding to the successive elimination of three acetyl groups. In the IR spectrum of (2) the band of active hydrogen had disappeared and the absorption band of an ester group had appeared at 1773 cm -1.

The new N-benzyltetrahydroisoquinoline alkaloid nummularine has been isolated from the leaves of Berberis nummularia. On the basis of a study of its spectral characteristics (PMR, iR, and mass spectra), the structure of mmmmlarine has been established as 6-hydroxy-N-(3'-hydroxy-4'-methoxybenzyl)-7-methoxy-1-methyltetrahydroisoquinoline. Continuing an investigation of alkaloids of plants of the Berberis genus, we have studied the alkaloid composition of the leaves of B. nurmnu/an'a gathered in the Naukatskii region of the Oshskaya oblast in the phase of incipient fruit formation. We have previously isolated a number of new alkaloids in an investigation of the epigeal organs of this plant [3,4].By chloroform extraction of the leaves we obtained 0.24% of total alkaloids. The chromatography of this material on a column of silica gel led to the isolation of noroxyhydrastinine, glaucine, isoboldine, corypalline, oxyacanthine, isocorydine, obaberine, aromoline, and berbamnnine, and the new base nummularine (1). The known alkaloids were identified from their spectral characteristics and also by comparison with authentic specimens.Nummularine is an optically active crystalline base with the composition C19I-I23NO 4. Its UV spectrum showed the maximum in the 284 nm region that is characteristic for tetrahydroisoquinolines. The mass spectrum revealed peaks of ions with m/z 329 (M+), 314 (M -15), 192, 178, 137 (100%). The mass-spectral fragmentation of nummularine under electron impact was characteristic for alkaloids of the 1-methyl-N-benzylisoquinoline series [3,4]. The appearance of an ion with m/z 314 (M -15) showed the presence of a methyl substituent at C-l, and that of an ion with m/z 192 and of the maximum ion with m/z 137 showed that there are methoxy and hydroxy substiments in rings A and C.The methylation of (1) with diazomethane gave the O,O-dimethyl ether (2), identical, according to TLC and its IR spectrum, with O-methylberuumicine [3]. The passage to O-methylbernumicine showed that the substiments in rings A and C occupy the 6,7-and 3',4'-positions.The PMR spectrum of nummularine (1) showed four one-proton multiplets at 2.75, 3.25, 2.88, and 2.96 ppm, which are characteristic for the protons of the interconnected methylene groups of tetrahydroisoquinoline alkaloids, two one-proton doublets at 3.76 and 3.87 ppm with the SSCC J = 13.0 Hz, a three-proton doublet at 1.55 ppm (J = 6.5 Hz), a one-proton quartet at 3.96 ppm (J = 6.5) Hz, and two singlets from the protons of methoxy groups at 3.98 and 4.03 ppm in the aliphatic part of the spectrum.

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UDC 547.944/945 + 543.51The alkaloid composition of the leaves of Berberis turcomanica has been studied. Together with known 1-benzylisoquinoIine alkaloids, we isolated a new one -turcomanidine, the structure of which has been established by chemical transformations and a study of spectral characteristics. Of the known alkaloids, N-methylcorydaldine has been detected in plants of the Berberis genus for the first time.The isolation of a number of isoqulnoline alkaloids from Berberis turcomanica has been reported previously [1][2][3]. Continuing a study of this plant, we have extracted leaves gathered in the phase of incipient fruit formation in the environs of the village of Khodzha-kala-2, Republic of Turkmenistan, in June, 1995. The total alkaloids were isolated by chloroform extraction in a yield of 0.11%. From this material, by column chromatography, we isolated the known alkaloids glaucine, thalicmidine, isocorydine, oxyacanthine, and berberine [3], and also armepavine, base (1) with mp 125-126"C, and base (2) in the form of an oil. The known alkaloids were identified from their physicochemical constants and spectral characteristics and by comparison with authentic specimens.In the UV spectrum of (1) there were absorption maxima at 223, 261, and 297 nm, which are characteristic for isoquinolones [4]. The IR spectrum contained an absorption band showing the presence of an amide carbonyl group (1639 cm-1). The mass-spectrometric fragmentation of (1) confirmed this fact and also showed that (1) was a simple isoquinolone alkaloid: the spectrum revealed intense peaks of ions with m/z 178 and 150 formed by the successive elimination of CH2NCH 3 and CO groups. The PMR spectrum of (1) corresponded to that of the alkaloid N-methylcorydaldine [5]. The results obtained enabled (1) to be identified as N-methylcorydaldine [5, 6], this being the first time that it has been isolated from the Berberidaeeae family.Compound (2) was an optically inactive base of phenolic nature. It formed a hydrobromide with nap 200-202"C. Its UV spectrum was similar to that of papaverine [7], which showed the closeness of these alkaloids. This was also confirmed by the mass spectrum, in which the strongest peaks were those of the molecular ions M + with m/z 311 and of the (M -1) + and (M -15) + ion, with m/z 310 and 296, respectively. The same fragmentation is observed in the mass spectra of papaverine [8] and turcomanine [3].The fact that base (2) was a 1-benzylisoquinoline was also confirmed by its PMR spectrum taken in deuterochloroform. It contained two three-proton singlets from two methoxy groups and a two-proton singlet from the methylene group of the benzyl moiety of the molecule, and in the aromatic region there were two one-proton doublets in a weaker field with a spin-spkn coupling constant (SSCC) J = 6.0 H.z, two one-proton singlets, and one three-proton broadened singlet at 6.65 ppm (see the Experimental part). Analysis of the spectral characteristics of (2) and of turcomanine [3] showed that the new alkaloid that we had isolated...

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