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1.
A method for measuring specific activities of 14C-labelled compounds by gas chromatography-mass spectrometry-computer system (GC-MS-CPU) was developed. This method was proved to provide practically precise and accurate specific activities of various 14C-labelled compounds with such merits as requirement of small amount of samples, being applicable to volatile compounds, and convenience. The C.V. percent obtained for tested compounds was within 3.9 and the reliable sensitivity should be over 37 MBq/mM (1 mCi/mM). This method was also useful for obtaining information on the labelling pattern and the synthetic procedures applied.  相似文献   

2.
The basicity of the symmetrical and unsymmetrical tetraphenylporphyrins, namely 5,10,15,20-tetraphenylporphyrin (I) (references), 5-(4-nitrophenyl)-10,15,20-triphenylporphyrin (II), a mixture of 5,10-bis(4-nitrophenyl)-15,20-diphenylporphyrin and 5,15-bis(4-nitrophenyl)-10,20-diphenylporphyrin (III), 5,10,15-tris(4-nitrophenyl)-20-phenylporphyrin (IV), 5,10,15,20-tetrakis(4-nitrophenyl)porphyrin (V), 5-(4-aminophenyl)-10,15,20-triphenylporphyrin (VI), a mixture of 5,10-bis(4-aminophenyl)-15,20-diphenylporphyrin and 5,15-bis(4-aminophenyl)-10,20-diphenylporphyrin (VII), 5,10,15-tris(4-aminophenyl)-20-phenylporphyrin (VIII) and 5,10,15,20-tetrakis(4-aminophenyl)porphyrin (IX), was investigated potentiometrically in nitrobenzene solvent. This investigation showed that these compounds are basic rather than acidic. Although they can not be titrated even with tetrabuthylammonium hydroxide, they can easily be titrated with perchloric acid to give well shaped and stoichiometric end-points. In addition they all undergo two proton reactions per porphyrin molecule. However, compounds VI, VII, VIII and IX each shows a second end-point to give three, four, five and six proton reactions, respectively, per porphyrin molecule. Half neutralization potentials (measures of their basicity) of these compounds are: I=368, II=409, III=432, IV=461, V=520, VI=340, VII=302, VIII=238 and IX=225 mV versus Ag/AgCl in methanol. These potentials clearly indicate that, if para-hydrogen with respect to the porphyrin core of tetraphenylporphyrin (I) is replaced with an acidifying nitro group (II, III, IV and V) the basicity of I decreases. This decrease is approximately proportional to the number of nitro groups. Each nitro group decreases the half neutralization potential by about 35 mV. On the other hand, if para-hydrogen indicated above is replaced with a basifying amino group (VI, VII, VIII and IX) the basicity increases. This increase is also approximately proportional to the number of amino groups. Each amino group increases the half neutralization potential by about 36.7 mV. The values 35 and 36.7 mV indicate that in nitrobenzene solvent the electron releasing power of an amino group to the porphyrin system is a little stronger than the electron withdrawing power of a nitro group from the porphyrin system. All these observations reveal that the nitrogen atoms at the core of the porphyrin molecules are strongly influenced by changes at the periphery of the molecules, which is a very good indication that the substituted phenyl groups and the cores of the porphyrins are nearly in the same plane.  相似文献   

3.
Oxidation of 2-[2-(3-indolyl)ethyl]-1,2,3,4-tetrahydroisoquinoline (I) with mercuric acetate gave 5,6,8,9,14,14b-hexahydrobenz[a]indolo[3,2-h]quinolizine (IV) and 8,9-dihydro-14H-benz[a]indolo[3,2-h]quinolizin-7-ium iodide (VI), as well as starting material. The base (IV) was oxidized with iodine and potassium acetate to VI and on Palladium carbon - maleic acid dehydrogenation yielded 5,6-dihydro-14H-benz[a]indolo[3,2-h]-quinolizin-7-ium iodide (IX), and 14H-benz[a]indolo[3,2-h]quinolizin-7-ium iodide (X). Heating the iodide (VI) with Palladium-carbon brought about an irreversible rearrangement to VII and both these salts with base yielded the red anhydro base 8, 9-dihydrobenz[a]indolo[3,2-h]quinolizine (VIII). This base was also obtained from IV by oxidation in air. The corresponding 8, 9-dehydroanhydro base (XI), benz[a]indolo[3,2-h]quinolizine, was readily obtained from X and alkali. The quinolizinium salts (VI), (VII), and (IX), on catalytic, zinc dust and acetic acid, or sodium borohydride reduction, regenerated the base (IV). Selenium degradation of IV gave, among other products, 1-(2-ethylphenyl)-β-carboline. An analogous series of products was obtained with the 6, 7-dimethoxy derivative of I. Various other aspects of these and related transformations are described.  相似文献   

4.
The Diels-Alder reaction of fluoranil with cyclopentadiene, 1,3-butadiene, and 1-acetoxy-1,3-butadiene gave 1,4, 5, 8-bis(methylene)-4a, 8a, 9a, 10a-tetrafluoro-1, 4, 4a, 5, 8, 8a, 9a, 10a-octahydroanthraquinone (I), 2, 3, 4a, 8a-tetrafluoro-4a, 5, 8, 8a-tetrahydro-1,4-naphthoquinone (III), and 5-acetoxy-2, 3, 4a, 8a-tetrafluoro-4a, 5, 8, 8a-tetrahydro-1,4- naphthoquinone (VI), respectively. Hydrogenation of I gave the expected saturated diketone(II). Hydrogenation of III afforded, with elimination of the two tertiary fluorines, 2,3-difluoro-5, 6, 7, 8-tetrahydro-1, 4- dihydroxynaphthalene (IV). In hydrogenation of VI, acetic acid and two moles of hydrogen fluoride were eliminated to give 2,3-difluoro-1, 4-dihydroxynaphthalene(VII). Both dihydroxy compounds IV and VII yielded on oxidation with ferric chloride the corresponding quinones, 2, 3- difluoro-5, 6, 7, 8-tetrahydro-1, 4-naphthoquinone (V) and 2, 3-difluoro-1, 4-naphthoquinone (VIII), respectively. Equivalent amounts of compounds IV and V gave a red-brown semiquinone IX, and a mixture of VI and VIII gave a dark-violet semiquinone X.  相似文献   

5.
By reactions of nucleophilic substitution of the halogen atom in 5-halo-1,2,3-thiadiazoles (IV), we have obtained 5-amino- (I, V), hydrazino-(VI, VII, IX, X), and mercapto- (VIII) 1, 2, 3-thiadiazoles. We show that upon reaction with amines, a mixture of 5-amino-1, 2, 3-thiadiazoles (I) and 5-mercapto-1, 2, 3-triazoles (II) is formed, and also the reaction product of compounds I and IV,: the selectivity of this process depends only on the type of solvent.Organic Synthesis Technology Department, Urals State Technical University—UPI, Ekaterinburg 620002. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 554–559, April, 1994. Original article submitted February 28, 1994.  相似文献   

6.
Aroylphenylacetylenes reacted with ammonium dithiocarbamate and ammonium hydrogen sulfide in 60% dioxane-waler mixture at 15° to give mainly a mixture of the corresponding β-hydroxy-α-thiobenzoylstyrene derivatives (III) and (E,Z)-β,β'-di(α-aroylstyryl) sulfides (IV), whereas with sodium xanthate and sodium sulfide they gave only (III). However, when benzoyl-(Ia) or p-ehlorobenzoyl-(Id)phenylacetylenes was refluxed with ammonium dithiocarbamate in ethyl alcohol, it gave a mixture of (IIIa or d) and the (E,E)-β,β'-di(α-aroylstyryl) sulfide (VIa or d). β-Hydroxy-α-thiobenzoylstyrene derivatives (III), (E,Z)-(IV) and (E,E)-(VI)-β,β'-di(α-aroylstyryl) sulfides reacted with hydrazine hydrate and phenylhydrazine to give 3(5)-aryl-5(3)-phenyl-(IX)- and 5-aryl-1,3-diphenyl-(X)pyrazoles, respectively. The former compounds (III) reacted with guanidine and ethyl hydrazinecarboxylate to give the corresponding aminopyrimidines (XIII) and acetophenone-N-ethoxycarbonyl hydrazones (XI), respectively.  相似文献   

7.
The reaction between phenol and trans penta-2,4-dienyl chloride gave trans penta-2,4-dienyl Phenyl ether (I), whereas with a mixture of sorbyl chloride and 1-methylpenta-2,4-dienyl chloride, pure trans, trans hexa-2,4-dienyl phenyl ether (IV) and trans 1-methylpenta-2,4-dienyl phenyl ether (V) were obtained. The ether I gave, on heating in dilute solution at 185°, 4-(penta-2,4-dienyl)-phenol (III) as the main product, and also some 2-(2-vinylallyl)-phenol (II). The ether IV provided, on heating at 165°, in addition to the ortho CLAISEN rearrangement product VI, mainly a mixture consisting of 94% 4-(1-methylpenta-2,4-dienyl)-phenol (VIII) and only 6% 4-(hexa-2,4-dineyl)-phenol(IX). The latter product (IX) was the only para isomer produced on heating ether V, but in addition 22% of the ortho rearrangement product VII was formed. The migrations I → III, IV → VIII, and V → IX, proceeding through a ten membered transition state, are the first [5,5] sigmatropic rearrangements described.  相似文献   

8.
Benzyl-14C-1-[bis(4-fluorophenyl)methyl]-4-(2,3,4-trimethoxybenzyl) piperazine dihydrochloride (14C-KB-2796), a new cerebral vasodilator, was synthesized in order to investigate the metabolic fate. The synthesis of carboxy-14C-2,3,4-trimethoxybenzoic acid (IV) was accomplished by the reaction of 2,3,4-trimethoxybromobenzene (II) with ter-butyllithium followed by carboxylation with 14C-carbon dioxide generated from 14C-barium carbonate. Formyl-14C-2,3,4-trimethoxybenzaldehyde (VI) was prepared by the reduction of the methyl ester of IV. The free base of 14C-KB-2796 was obtained by the condensation of VI with bis(4-fluorophenyl)methyl-piperazine, and converted to I. An overall radiochemical yield from 14C-barium carbonate was 39%, the specific activity was 1,816.7 MBq/mmol (49.1 mCi/mmol) and its radiochemical purity was 99% in reverse isotope dilution analysis and thin layer chromatographic method.  相似文献   

9.
Treatment of 4,5 -dihydrocanthin-6-one (V) (prepared from synthetic canthinone (IV)) with ethyl or methyl magnesium iodide and methanolic hydrochloric acid yielded the ethyl or methyl compounds VI and IX. Oxidation of the latter compounds with selenium dioxide in dimethylformamide gave rise to the Pleiocarpa alkaloids isotuboflavine (II) and norisotuboflavine (III) in low yields. Deethyltuboflavine (VIII) was isolated as a byproduct from further oxidation of norisotuboflavine.  相似文献   

10.
10,12-Heneicosadiynoic acid (I), 5,7-hexadecadiynoic acid (IV), and 10,12-docosadiynedioic acid (VI) were fed to rats. As metabolites 4,6-undecadiynedioic acid (II), 5,7-dodecadiynedioic acid (V), and 4,6-decadiynedioic acid (VII) respectively were isolated from the urine. 10,12-Heptadecadiynoic acid (III) also yielded metabolite II. Furthermore 9,11-eicosadiyne (X) and for comparison purposes eicosane (XI), hexadecanedioic acid (VIII), and docosanedioic acid (IX) were fed. X and XI were incorporated into depot fat and liver lipids to a cetain degree. The diynes I, II, IV, and X are new compounds.  相似文献   

11.
The syntheses and some reaetions of N,N'-diamino-2,2′- and 4,4′-bipyridinium salts (IV, V and VI) are described. These compounds are prepared by the reaction of bipyridyls (I-III) with O-mesitylenesulfonylhydroxylamine in moderate to good yields. Compounds IV and VI were found to give the N,N'-diacyl derivatives by the reaction with acyl chlorides and to undergo 1,.3-dipolar cycloaddition reaction with an acetylenic compound to give 1:2 adducts. Photo-irradiation of N,N'-dibenzoylimino-2,2′-bipyridinium betaine (IX) isomerizes to a mono diazepine derivative (XVI).  相似文献   

12.
Phenolic cyclization of 2-(3-hydroxyphenyl)-2-methylethylamine (XIIIa) and 2-(3-hydroxyphenyl)phenethylamine (XIIIb) with various carbonyl compounds afforded eight types of corresponding 1-spirocycloalkano- and 1-spiroheterocycloalkano-1,2,3,4-tetrahydroisoquinoline derivatives (1-VIII) and 1,1-disubstituted-1, 2,3,4-tetrahydroisoquinoline derivative (IX). The acetyl derivatives of VI and IX and the benzoyl derivatives of III and V were also prepared. In addition, a synthetic method for obtaining the starting phenethylamines was examined.  相似文献   

13.
The nitro-imidazolines V and VI are formed by addition reaction of ethylenediamine to the isothiocyanates III and IV. The nitro group is then converted by hydrogenation to the amino group, giving XI and XII, which can be acylated selectively to IX and X. By rearrangement in boiling xylene, the compounds XI and XII give the corresponding 2-(2-aminoethylamino)-benzimidazoles XIII and XIV. The benzoylated derivative IX gives the benzimidazole derivative XVIII by rearrangement and subsequent migration of the benzoyl group, while the benzylated derivative XVI gives the rearranged benzimidazole XXII. The benzimidazole structure of the rearranged products is proven by unambiguous synthesis of XIII, starting with 2-chlorobenzimidazole (VII) and mono-N-acetyl-ethylene-diamine to give compound VIII, from which XIII is obtained by hydrolysis.  相似文献   

14.
气相色谱-质谱法研究多卤代产物的组成和结构   总被引:1,自引:1,他引:0  
江焕峰 《色谱》1997,15(4):278-280
在制备取代的1,4-己二烯过程中,在钯(Ⅱ)催化下烯丙基溴对1,4-二氯-2-丁炔的加成反应生成了一系列未曾预料的复杂产物,运用气相色谱-质谱法(GC-MS)对产物进行了逐个分析。分析结果显示:(1)8个化合物中除两个为预期产物外,其余均为氯和溴交换反应的副产物,并且8个化合物中的每两个为一对几何异构体;(2)4对几何异构体中Z/E的比例随着分子量的增加而逐渐下降。  相似文献   

15.
The aims of the present study were to determine the antibacterial activity of bark extract of Cryptomeria japonica D. Don and to isolate potential antibacterial constituents. The results showed that the ethanolic extract of C. japonica bark possessed a good antibacterial activity. Nine compounds including seven diterpenoids (ferruginol (I), isopimaric acid (II), iguestol (III), isopimarol (IV), phyllocladan-16alpha-ol (V), sandaracopimarinol (VI) and sugiol (VII)) and two steroids (beta-sitosterol (VIII) and beta-sitostenone (IX)) were isolated from active subfractions; beta-sitostenone was isolated for the first time from this plant. Among these compounds, ferruginol possessed the strongest antibacterial activity and had MIC values ranging from 6.3 to 12.5 microg mL(-1) against all bacteria tested. Isopimaric acid was also an antibacterial natural product. Cryptomeria japonica bark extract and its diterpenoids, ferruginol and isopimaric acid, have the ability to inhibit the bacterial growth and can be used as the source for natural bactericides.  相似文献   

16.
Summary 1,3-Cyclohexanedione was alkylated with branched allyl bromides. The resulting 2-alkyl derivatives (IV), (V), and (VI), and also their enol acetates (VII), (VIII), and (IX), have an antihelminthic action. The highest antihelminthic activity is shown by the enol acetate (IX).  相似文献   

17.
Six new uranium phosphites, phosphates, and mixed phosphate-phosphite compounds were hydrothermally synthesized, with an additional uranyl phosphite synthesized at room temperature. These compounds can contain U(VI) or U(IV), and two are mixed-valent U(VI)/U(IV) compounds. There appears to be a strong correlation between the starting pH and reaction duration and the products that form. In general, phosphites are more likely to form at shorter reaction times, while phosphates form at extended reaction times. Additionally, reduction of uranium from U(VI) to U(IV) happens much more readily at lower pH and can be slowed with an increase in the initial pH of the reaction mixture. Here we explore the in situ hydrothermal redox reactions of uranyl nitrate with phosphorous acid and alkali-metal carbonates. The resulting products reveal the evolution of compounds formed as these hydrothermal redox reactions proceed forward with time.  相似文献   

18.
Five new withanolide derivatives (1, 9-12) were isolated from the roots of Withania somnifera together with fourteen known compounds (2-8, 13-19). On the basis of spectroscopic and physiochemical evidence, compounds 1 and 9-12 were determined to be (20S,22R)-3 alpha,6 alpha-epoxy-4 beta,5 beta,27-trihydroxy-1-oxowitha-24-enolide (1), 27-O-beta-D-glucopyranosylpubesenolide 3-O-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranoside (withanoside VIII, 9), 27-O-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosylpubesenolide 3-O-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranoside (withanoside IX, 10), 27-O-beta-D-glucopyranosylpubesenolide 3-O-beta-D-glucopyranoside (withanoside X, 11), and (20R,22R)-1 alpha,3 beta,20,27-tetrahydroxywitha-5,24-dienolide 3-O-beta-D-glucopyranoside (withanoside XI, 12). Of the isolated compounds, 1, withanolide A (2), (20S,22R)-4 beta,5 beta,6 alpha,27-tetrahydroxy-1-oxowitha-2,24-dienolide (6), withanoside IV (14), withanoside VI (15) and coagulin Q (16) showed significant neurite outgrowth activity at a concentration of 1 microM on a human neuroblastoma SH-SY5Y cell line.  相似文献   

19.
Combined with medium-pressure liquid chromatography (MPLC) and preparative high-pressure liquid chromatography (Prep-HPLC), high-speed countercurrent chromatography (HSCCC) was successfully applied for separation and purification of isoflavonoids from the extract of belamcanda. HSCCC separation was performed on a two-phase solvent system composed of methyl tert-butyl ether -ethyl acetate - n-butyl alcohol - acetonitrile -0.1% aqueous trifluoroacetic acid at a volume radio of 1:2:1:1:5. Semi-purified peak fractions from HSCCC separation were further purified by Prep-HPLC. Nine well-separated fractions were analyzed by HPLC-UV absorption spectrometry to determine their purities and characterized with ESI-MS(n). Except for peaksland VII (unknown) seven compounds were identified as apocynin (peak II), mangiferin (peak III), 7-O-methylmangiferin (peak IV), hispidulin (peak V), 3'-hydroxyltectoridin (peak VI), iristectorin B (peak VII), isoiridin (peak IX).  相似文献   

20.
The reaction of 1,3-diaryl-2-propene-1-ones I with arylacetamides II, in the presence of sodium ethoxide under reflux, for two hours, gave the corresponding 3,4,6-triaryl-3,4-dihydro-2(1H)-pyridones IV. However, when the reaction of these ketones was carried out in the presence of sodium hydride, they gave the corresponding 3,4,6-triaryl-2(1H)-pyridones VI or a mixture of IV and VI. When 1,3-diaryl-2-propyne-1-ones V were reacted with arylacetamides, in the presence of sodium hydride, they yielded the corresponding 2-pyridones VI. Treatment of compounds IV with selenium produced the corresponding 2-pyridones VI. Acetylation of the latter compounds gave the corresponding 2-acetyl derivatives VIII. The structure of all products was confirmed by chemical and spectroscopic evidence, and the mechanism of the reactions was discussed.  相似文献   

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