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1.
Isolation, characterization, and biological evaluation of active components of Colchicum stevenii Kunth (Colchicaceae) are described. Colchicum stevenii is an unexplored Jordanian specie with toxic reputation. Directed by brine shrimp lethality test (BST), methanolic extraction, liquid-liquid partition, preparative TLC, and semi-preparative HPLC, it resulted in the isolation of six cytotoxic compounds. The compounds, reported for the first time from this specie, are: (-)-colchicine (1), 2-demethyl-(-)-colchicine (2), (-)-cornigerine (3), beta-lumicolchicine (4), (-)-isoandrocymbine (5) and (-)-O-methylandrocymbine (6). A new, in-house developed, acidic-based reverse-phase gradient semi-preparative HPLC method for the separation of colchisides is presented here. Structural elucidation was based on spectroscopic techniques principally; 1H-NMR and low resolution EIMS. Based on BST results, reported as LC50 values in microg mL(-1) (ppm) with 95% confidence intervals, (-)-colchicine (2.5 ppm) and (-)-cornigerine (2.7 ppm) were the most potent.  相似文献   

2.
As part of our continuing investigation of Jordanian Colchicum species, (-)-colchicine content in C. brachyphyllum Boiss. & Haussk. ex Boiss and Colchicum tunicatum Feinbr (Colchicaceae), growing wild in Jordan, was determined during different growth stages. Using external reference standard, a reverse-phase gradient photo-diode array high performance liquid chromatography (PDA-HPLC) method was adapted. Underground parts in both species and during different growth stages, always showed higher (-)-colchicine content than the above ground parts. In C. brachyphyllum total (-)-colchicine content of underground parts during flowering stage was found to be about 0.15% (wt/wt), while that of aerial parts was only about 0.04% (wt/wt). In C. tunicatum total (-)-colchicine content of underground parts was found to be 0.12% (wt/wt), and 0.13% (wt/wt) during flowering and vegetating stages, respectively, while that of aerial parts was only about 0.04% (wt/wt) and 0.02% (wt/wt), respectively. In C. tunicatum, stems, roots and unripe seeds are the main storages of (-)-colchicine at flowering, vegetating and seeding stages, respectively, while in C. brachyphyllum, corms are the main storage of (-)-colchicine at flowering and seeding stages.  相似文献   

3.
Corms of Colchicum hierosolymitanum and Colchicum tunicatum were collected, identified and planted under field condition. We report here and for the first time the presence of colchicine in an appreciable amount in both species. The effect of different NPK fertilizer levels on colchicine content of the two Colchicum species at different growth stages were evaluated by HPLC. Results indicated that increasing NPK fertilizer levels significantly improve colchicine content in different plant parts and stages. The highest colchicine content observed in corms was at maturity stage 0.766 mg/g and 0.688 mg/g dry weight with C. hierosolimitanum and C. tunicatum, respectively.  相似文献   

4.
The fraction of weak bases fromColchicum speciosum Stev. (family Liliaceae) has yielded a new compound — specioseine. The structure of 10-demethylspeciosine has been established for this base by chemical and spectral methods.V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 253–258, March–April, 1991.  相似文献   

5.
Four new lanostane triterpene lactones (colossolactone I, colossolactone II, colossolactone III and colossolactone IV) were isolated from the Vietnamese mushroom Ganoderma colossum (FR.) C. F. BAKER along with five known compounds. The structures of the new compounds were determined on the basis of MS, NMR and circular dichroism.  相似文献   

6.
Synthesis of perfluorophenylcyclopropane (I) and I-chloro-I-pentafluorophenyltetrafluorocyclopropane (II) is described and their pyrolysis at 620°C is studied. Pyrolysis of compounds (I) and (II) is shown to give perfluorostyrene (III) and α - chloroheptafluorostyrene (IV) as the main products, together with a small amount of perfluoroindan (V) and I-chlorononafluoroindan (VI), respectively. Styrene (III) was obtained by bromofluorination of styrene (IV) and subsequent dehalogenation of the resultant α - chloro- β - bromooctafluoroethylbenzene (VII).  相似文献   

7.
By controlled Anderson type rearrangement reactions complexes of the general formula trans-[Os(IV)Cl(4)(Hazole)(2)], where Hazole = 1H-pyrazole, 2H-indazole, 1H-imidazole, and 1H-benzimidazole, have been synthesized. Note that 2H-indazole tautomer stabilization in trans-[Os(IV)Cl(4)(2H-indazole)(2)] is unprecedented in coordination chemistry of indazole. The metal ion in these compounds possesses the same coordination environment as ruthenium(III) in (H(2)ind)[Ru(III)Cl(4)(Hind)(2)], where Hind = 1H-indazole, (KP1019), an investigational anticancer drug in phase I clinical trials. These osmium(IV) complexes are appropriate precursors for the synthesis of osmium(III) analogues of KP1019. In addition the formation of an adduct of trans-[Os(IV)Cl(4)(Hpz)(2)] with cucurbit[7]uril is described. The compounds have been comprehensively characterized by elemental analysis, EI and ESI mass spectrometry, spectroscopy (IR, UV-vis, 1D and 2D NMR), cyclic voltammetry, and X-ray crystallography. Their antiproliferative acitivity in the human cancer cell lines CH1 (ovarian carcinoma), A549 (nonsmall cell lung carcinoma), and SW480 (colon carcinoma) is reported.  相似文献   

8.
Three C(90) fractions were isolated by multi-step HPLC from fullerene soot obtained from direct current (DC) arc discharge of undoped graphite rods. C(90) of each fraction was chlorinated with VCl(4) or SbCl(5) in ampoules at 290-310 °C, affording a series of C(90)Cl(n) compounds. Single-crystal X-ray crystallography with the use of synchrotron radiation resulted in structure elucidation of seven C(90)Cl(n) compounds containing six different isolated pentagon rule (IPR) C(90) cages (the number of the C(90) isomer is given in the parentheses): C(90)(46)Cl(32) (I), C(90)(34)Cl(32) (II), C(90)(35)Cl(24) (III), and C(90)(35)Cl(28) (IV), C(90)(32)Cl(24) (V as co-crystals with III), co-crystals of C(90)(30)Cl(22) and C(90)(28)Cl(24) (VI), and C(90)(28)Cl(24) (VII). Cage connectivities of C(90) isomers 35 and 28 have been crystallographically confirmed for the first time. The chlorination patterns of the C(90)Cl(n) molecules are discussed in terms of the formation of isolated aromatic systems and isolated C=C double bonds on the fullerene cage. The distribution of six C(90) isomers in three HPLC fractions is compared with data from the literature.  相似文献   

9.
In the course of continuing search for the constituents of the root-bark of Hemandiu ovigera L., led to the isolation of eight compounds: desoxypodophyllotoxin(I), thalicarpine(III)) dehydrothalicarpine(IV), ovigerine(V), hernangerine(VI), hernandonine(VIII) and two unknown substances, mp. 219–220° and mp. 269–270°. Desoxypodophyllotoxin( I) and thalicarpine(III) exhibited a distinctively cytotoxic activity against nasopharynx carcinoma was reported by S. M. Kupchan et.al3,9. Dehydrothalicarpine( IV) is merely a dehydro product of thalicarpine(III) at C–6a and C–7 of aporphine moiety. The isolation of dehydrothalicarpine(IV) made the first instance from Hernandia ovigera L. Comparison of their components distribution in each part of Hernandia ovigera was shown in Table I.  相似文献   

10.
A new diterpene, 16-hydroxy communic acid (1), along with thirty one known compounds including five norditerpenes (2-6), twenty two flavonoids containing four biflavonoids (7-10), nine monoflavonoids (11-19) and nine flavanoid glycosides (20-28), as well as four phenolic constituents (29-32) were isolated from the 95% ethanolic extract of Podocarpus fasciculus. The structure of 1 was elucidated using spectral methods. Of these isolates, nagilactone C (2) showed the most significant inhibitory effects against DLD cells (human colon carcinoma) (ED(50)=2.57 microg/ml) and compounds 7, 8, 10, 11, and 12 had moderate cytotoxic activity against human KB (human oral epithelium carcinoma), Hela (human cervical carcinoma), Hepa (human hepatoma), DLD (colon carcinoma), and A-549 (human lung carcinoma) tumor cell lines. Preliminary structure-activity relationship studies of the isolated diterpenoids and biflavonoids are discussed.  相似文献   

11.
High-speed counter-current chromatography combined with macroporous resin column separation was applied to the isolation and purification of genistein-7,4'-di-O-beta-D-glucoside (I), genistein-7-O-beta-D-glucopyranoside-4'-O-[(alpha-L-rhamnopyransoyl)-(1-2)-beta-D-glucopyranoside] (II), kaempferol-3-O-beta-D-sophoroside(III), quercetin-3-O-beta-L-ramnopyranosyl-(1 - 6)-beta-D-glucopyranoside (IV), genistein-4'-beta-L-rhamnopyransoyl-(1 - 2)-alpha-D-glucopyranoside (V), and kaempferol-3-O-beta-L-ramnopyranosyl-(1 - 6)-beta-D-glucopyranoside (VI) from the Chinese medicinal herb Sophora japonica L. The crude extracts from the pericarps of Sophora japonica L. were pre-separated on a D-101 macroporous resin column and divided into two parts as sample 1 and sample 2. An 80-mg portion of sample 1 was separated by using n-butanol-acetic acid (1%) (5:5, v/v) as the two-phase solvent system and yielded 30.1 mg of compound I, 23.3 mg of compound II. A 120 mg portion of sample 2 was separated by using ethyl acetate-n-butanol-acetic acid (1%) (5:0.8:5, v/v) as the two-phase solvent system and yielded 5.5 mg of compound III, 31.7 mg of compound IV, 37.4 mg of compound V, and 6.2 mg of compound VI. The purities of compounds I, II, III, IV, V, and VI were 98.7, 98.2, 97.8, 98.5, 99.3, and 98.9%, respectively, as determined by HPLC. The chemical structures of these components were identified by 1H-NMR and 13C-NMR.  相似文献   

12.
Two spectrophotometric methods, derivative and multivariate methods, were applied for the determination of binary, ternary, and quaternary mixtures of the water-soluble vitamins thiamine HCI (I), pyridoxine HCI (II), riboflavin (III), and cyanocobalamin (IV). The first method is divided into first derivative and first derivative of ratio spectra methods, and the second into classical least squares and principal components regression methods. Both methods are based on spectrophotometric measurements of the studied vitamins in 0.1 M HCl solution in the range of 200-500 nm for all components. The linear calibration curves were obtained from 2.5-90 microg/mL, and the correlation coefficients ranged from 0.9991 to 0.9999. These methods were applied for the analysis of the following mixtures: (I) and (II); (I), (II), and (III); (I), (II), and (IV); and (I), (II), (III), and (IV). The described methods were successfully applied for the determination of vitamin combinations in synthetic mixtures and dosage forms from different manufacturers. The recovery ranged from 96.1 +/- 1.2 to 101.2 +/- 1.0% for derivative methods and 97.0 +/- 0.5 to 101.9 +/- 1.3% for multivariate methods. The results of the developed methods were compared with those of reported methods, and gave good accuracy and precision.  相似文献   

13.
The compounds alpha-TlBiP2Se6 (I), beta-TlBiP2Se6 (II), TlBiP2S6 (III), Tl3Bi3(PS4)4 (IV), TlBiP2S7 (V), and Tl3Bi(PS4)2 (VI) were synthesized, and the structures of I-V were determined by single-crystal X-ray diffraction analysis. The structure of I features infinite chains. Those of compounds II, III, and V are layered. The structure of IV features a three-dimensional framework. Tl4Bi2(PS4)2(P2S6) (VII) was also prepared for comparison to the title compounds. The band gaps of each compound are 1.23, 1.27, 1.81, 1.88, 2.06, 1.98, and 1.97 eV for I-VII, respectively. Compounds I, III, IV, and VI melt congruently at 544, 595, 495, and 563 degrees C, respectively, and compounds II, V, and VII melt incongruently at 544, 509, and 600 degrees C, respectively. Solid-state 31P NMR spectroscopy of the reported compounds demonstrates chemical shifts and chemical shift anisotropies in line with related chalcophosphate materials. Evidence for two-bond P-Tl J coupling was observed in 31P NMR spectra (J=481-1781 Hz), and to the best of our knowledge, this is the first example of two-bond P-Tl J coupling and the first example of P-Tl coupling in the solid state. It was possible to assign chemical shifts of inequivalent 31P atoms from the same [PxQy]z- anion type based on different modes of metal ion coordination to the chalcogen. These assignments provide information about the vicinal metal ion contribution to the 31P chemical shift.  相似文献   

14.
Shoupu L  Mingqiao Z  Chuanyue D 《Talanta》1994,41(2):279-282
A reversed-phase high-performance liquid chromatographic separation and determination of beryllium(II), aluminium(III) and chromium(III) with chromotrope 2C chelates on a C18-bonded stationary phase is reported. Methanol-water (45:55 v/v) containing 6 x 10(-3)M tetra-n-butylammonium bromide (TBAB) and 2 x 10(-2)M acetate buffer solution (pH 6.0) as mobile phase and with spectrophotometric detection at 530 nm was applied. The method has high sensitivity, the detection limits being 0.2 ppb for beryllium(I), 1 ppb for aluminium(III) and 2 ppb for chromium(III). Under the optimum conditions, most other metal ions did not interfere, e.g. up to 2 mg of Hg(II), Sn(II, IV), Pb(II), Bi(III), Ag(I), Zn(II), Cd(II), Cu(II), 1.5 mg of Fe(II), Co(II), Ni(II), 1.2 mg of Ca(II), Mg(II), Sr(II), Ba(II), 1 mg of Ga(III), In(III), 0.5 mg of Fe(III), 1 mg of Ga(III), In(III), 0.5 mg of Fe(III), 0.4 mg of Th(IV), Zr(IV). The method can be applied to the simultaneous determination of trace amounts of beryllium(II), aluminium(III) and chromium(III), in water, rice, flour and human hair samples.  相似文献   

15.
New inorganic-organic hybrid open-framework materials of the phosphate-oxalate family, [Fe2(H2O)2-(HPO4)2(C2O4)].H2O (I), [Fe2(H2O)2-(HPO4)2(C2O4)].2H2O (II), [C3N2H12]-[Fe2(HPO4)2(C2O4)1.5]2 (III), and [C3N2OH12][Fe2(HPO4)2(C2O4)1.5]2 (IV) have been synthesized hydrothermally in the presence of structure-directing amines. The amine molecules are incorporated in III and IV, whereas I and II are devoid of them. The oxalate units act as a bridge between the layers in all the compounds. The layers in I and II are entirely inorganic, being formed by FeO6 and PO4 units, whereas in III and IV oxalate units constitute the inorganic layers and act as the bridge between these layers. Such a dual role of the oxalate unit is unique and noteworthy. The formation of two types of inorganic layers in I and II consisting of four-, six-, and eight-membered rings, indicates the interconversions between the various rings in the phosphate--oxalates to be facile. All the phosphate--oxalates show antiferromagnetic ordering at low temperatures.  相似文献   

16.
Jess I  Näther C 《Inorganic chemistry》2006,45(18):7446-7454
Five new coordination compounds were prepared, structurally characterized, and investigated for their thermal properties. In the structure of the ligand-rich 4:9 compound, tetra(mu2-chloro)bis(mu2-2,3-dimethylpyrazine-N,N')tetrakis(2,3-dimethylpyrazine-N)tetracopper(I) tris(2,3-dimethylpyrazine)solvate (I), discrete complexes are formed by build up of two [(CuCl-(2,3-dimethylpyrazine)2]2 dimers, which are connected by two 2,3-dimethylpyrazine ligands via mu-N,N' coordination. In the 1:1 compound poly[mu2-chloro-mu2-2,3-dimethylpyrazine-N,N'-copper(I)] (II), (CuCl)2 dimers are found, which are connected by the 2,3-dimethylpyrazine ligands into layers. For this composition, a second polymorphic modification was found (III), which exhibits a different topology of the coordination network and a different packing of the layers. In the most stable 3:2 compound catena[tri(mu2-chloro)bis(mu2-2,3-dimethylpyrazine-N,N')tricopper(I)] (IV), six-membered rings of (CuCl)3 are found, which are connected by the 2,3-dimethylpyrazine ligands into chains. In the ligand-deficient 2:1 compound, poly[di(mu3-chloro)(mu2-2,3-dimethylpyrazine-N,N')dicopper(I)] (V), CuCl double chains are found, which are connected by the 2,3-dimethylpyrazine ligands into layers. On heating, compound I transforms quantitatively into the 3:2 compound IV without the formation of II or III as intermediates. Compound IV is also obtained by heating either the 1:1 compound II or III. On further heating, the 3:2 compound IV loses additional ligands, forming the ligand-deficient 2:1 compound V, which then decomposes into CuCl. The stability, thermal reactivity, and the transition behavior of all compounds were investigated using different thermoanalytical methods. These results are compared with those previously reported for the structurally similar CuCl(2-ethylpyrazine) coordination compounds. The formation and the stability of the different compounds in solution were also investigated.  相似文献   

17.
Abstract

The condensation of the aliphatic spirotetraamine 2,2-bis(aminomethyl)-1,3-diaminopropane (I) or 1,4-bis(aminomethyl)-1,4-diaminocyclohexane (II) with pyromellitic dianhydride (III) or 1,4,5,8-naphthalenetetracar-boxylic dianhydride (IV) was studied. It was found that in polyphos-phoric acid at temperatures greater than 200°C and after long reaction times, either tetraamine produced the desired spiropolymer with the dianhydride (IV), but only tars could be isolated when the dianhydride (III) was used. Although these condensations proceed through a polyimide precursor which then cyclizes by elimination of water, condensations of (II) with (IV) only yielded the fully cyclized material and all attempts to isolate the imide precursor failed. Strong evidence for total cyclization was obtained by comparing the infrared and ultraviolet spectra of the polymer and of model compounds that were representative of the fully cyclized and imide forms. Condensations of (I) and (IV) yielded polymers that were only 50% cyclized. The polymer based on spirotetraamine (I) started to lose weight at 300°C in both air and vacuum, while the polymer based on amine (II) showed no weight loss until 500 C in vacuum and 400°C in air.  相似文献   

18.
Appearance energies for [M - H](-) ions from phenol (I), 4-chlorophenol (II), pentachlorophenol (III) and pentachlorothiophenol (IV) were measured. The following thermochemical data were deduced from experiment: DeltaH(acid) values of 343.3, 335.7, 317.1 and 317.1 kcal mol(-1) for RH molecules (I, II, III, and IV, respectively) and electron affinities (EAs) of R(.) free radicals 2.55, 2.90, 3.79, and 3.65 eV, respectively. Our data for phenol (I) and 4-chlorophenol (II) demonstrate a higher stabilization of ArO(-) anions than was previously accepted. Using the enthalpic shift procedure for molecules and a series of isodesmic reactions for free radicals, earlier elaborated by the authors, a new Delta$bf H_bf fbf 0$ values for the following gas-phase species were obtained (kcal mol(-1)): C(6)Cl(5)Br (5.0), C(6)Cl(5)SH (8.5), p-ClC(6)H(4)C(.) (2. 0), C(6)Cl(5)C(.) (-15), C(6)Cl(5)S(.) (44). Copyright 2000 John Wiley & Sons, Ltd.  相似文献   

19.
Girisopam possesses selective anxiolytic action without muscle relaxant and anticonvulsive activity. After a 100-mg oral dose of 14C-labelled girisopam to seven male subjects, the mean recovery of 14C radioactivity was 51% in urine and 33% in faeces. A high-performance liquid chromatographic method has been developed for studying girisopam in single-dose pharmacokinetic studies. The serum extract was chromatographed on a normal-phase column using a mobile phase of hexane-ethanol-diethyl ether (66:9:25, v/v) and ultraviolet detection at 235 nm. The recovery was 60% and the detection limit was 3 ng/ml, using 1 ml of serum. After a 20-min delay, girisopam is rapidly absorbed. After reaching a mean serum level of 178 ng/ml at a mean time of 2.0 h, the serum concentration of girisopam decreased with a mean elimination half-time of 22.2 h. The metabolites were separated by high-performance liquid chromatography, radio thin-layer chromatography and gas chromatography. Their structures were determined by liquid chromatography-mass spectrometry, mass spectrometry and gas chromatography-mass spectrometry. Their chemical structures were confirmed by comparison with synthesized reference compounds. The major urinary metabolites were 7-demethylgirisopam (I), 4'-hydroxygirisopam (II) and 4-hydroxymethyl-4-demethylgirisopam (III), which were in conjugated form, and 4-carboxy-4-demethylgirisopam (V), a compound with an open-chain structure (VII) and traces of 4-demethyl-4-oxogirisopam (VIII) and 4-hydroxymethyl-4-demethylgirisopam (III), which were in non-conjugated form. The metabolic profile in the serum consisted predominantly of the glucuronides of I, II and III. The non-conjugated metabolites were the metabolite with the open-chain structure (VII), III and V. Besides the parent compound, the faeces sample contained conjugates of I and II.  相似文献   

20.
从中国特有瑞香科植物古特瑞香的乙醇提取物中分得一新的抗生育活性二萜,命名为唐古特瑞香甲素(1)和三个已知活性二萜,GNIDITRIN(2),土沉香毒素(3)和瑞香毒素(4)以及棕榈酸(5).根据它们的光谱数据和化学反应分别确定其结构.其中化合物1对孕猴中期妊娠引产剂量300微克/只,羊膜控注射给药.  相似文献   

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