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1.
,-Dibromo--('-carbethoxyacetony)-,-butenolide (I) reacts with amines in diethyl ether solution to give -bromo-amino--('-carbethoxyacetony)-,-butenolides. Compounds n are converted to -bromo-amino--('-carbethoxyacetony)-,-butenolides on reaction with amines. The corresponding arylhydrazones (VI and VII) are obtained by the reaction of I and II with p-nitro- and 2,4-dinitrophenylhydrazines. Compound I reacts with phenylhydrazine to give furopyridazine VIII.See [1] for communication IV.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 867–871, July, 1972.  相似文献   

2.
Conclusions The addition of thioacetic acid to the 5 bonds of 16- and 16-mercapto-3-hydroxypregn-5-en-20-one 3,16-diacetates (II) and (III) under radical conditions gives not only trans-diaxial addition products-6,16- and 6,16-dimercapto-3-hydroxy-5o;-pregnan-20-one 3,6,16-triacetates (IV) and (V) -but also cis-addition products-6,16- and 6,16-dimercapto-3-hydroxy-5-pregnan-20-one 3,6,16-triacetates (VI) and (VII).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 405–411, February, 1969.  相似文献   

3.
Summary A GC-MS method has been studied for characterization and quantification of phytosterols, cholesterol and cholesterol oxidation products. Baseline separations have been achieved between cholesterol, cholesterol 5-6-epoxide, 5-cholestene-3-ol-7one (7-keto-cholesterol), cholestene-3-5-6-triol, 5-cholestene-3-25-diol (25-hydroxycholesterol), 5-cholestene-3-20-diol (20-hydroxycholesterol), 5-cholestene-3-7-diol (7-hydroxycholesterol) and 5-cholestene-3-19-diol (19-hydroxycholesterol) as well as between -cholestane, cholesterol, stigmasterol, campesterol and -sitosterol. Excellent linearity of response has been obtained permitting reliable quantification. The characterization of each derivatized sterol has been performed by mass-spectrometry. The results confirm the utility of combined gas chromatography-mass spectrometry in the analysis and characterization of sterols and cholesterol oxidation products.  相似文献   

4.
Literature information is given on the current state of the study of the chemical transformation of cycloartane triterpenoids. A method has been developed for the transformation of the genin part of glycosides of 20,24-epoxycycloartan-25-ols with retention of the carbohydrate constituents. Three 25-norglycosides have been synthesized from natural cyclosieversigenin glycosides, namely 16-acetoxy-3,6-dihydroxy-20R,25-norcycloartan-20,24-olide 3-O-[O--L-arabinopyranosyl-(12)--D-xylopyranoside] 6-O--D-xylopyranoside (VIII), sodium 3,6,16,20-tetrahydroxy-20R,25-norcycloartan-24-oate 6-O--D-glucopyranoside 3-O--D-xylopyranoside (XII), and 20R,25-norcycloartane-3,6,16,20,24-pentaol 6-O--D-glucopyranoside 3-O--D-xylopyranoside (XIII).Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 710–718, September–October, 1993.  相似文献   

5.
Summary The configuration 3, 15-dihydroxy-5, 9, 13, 12, 17, 22-8(14)-cevine has been proposed for korseveridine.Khimiya Prirodnykh Soedinenii, Vol. 4, No. 2, pp. 101–106, 1968  相似文献   

6.
Conclusions The reaction of diphenylchlorophosphine with ,,-trichloro--hydroxyethyl ethyl sulfide in the presence of triethylamine leads to the formation of -ethylthio-,,-trichloroethyl diphenylphosphonite. The reaction of diphenylchlorophosphine with dimethyl -hydroxy--propylthiophosphonate in the presence of triethylamine gives -propylthio--dimethylphosphonoethyl diphenylphosphonite. The phosphorylated hemimercaptals obtained are thermally unstable and decompose to S-alkyl diphenylthiophosphonites and the corresponding carbonyl compounds.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2619–2621, November, 1985.  相似文献   

7.
3-Chloro-5,7-dibromo-6-ketosteroids 5a and 5b are synthesized from -sitosterol (1a) and cholesterol (1b). Dehydrohalogenation of these forms 7-bromo-2,4-dien-6-ones (6a-b), 2,4-dien-6-ones (7a-b), and 14-hydroperoxy-2,4,7-trien-6-ones (8a-b). Woodward hydroxylation of dienone 6a produces 2-iodo-7-bromo-3-acetoxy-4-6-ketone 9 and 7-bromo-2,3-diacetoxy-4-6-ketone 10. 2-Iodo-3-acetoxy-4,7,14-trien-6-one 11 is prepared analogously from trienone 8a.  相似文献   

8.
The temperature dependence of the solubilities in water at pH 3.00 of a representative series of ten cholanoic acids (bile acids) were measured over the temperature range 10 to 50°C. The solubilities ranged from 5×10–8M for 3-hydroxy-5-cholanoic acid (lithocholic acid) to 2×10–3M for 3-7-12-trihydroxy-5-cholanoic acid (ursocholic acid). The solubilities increased with temperature and were found to be dependent on the number, position, and orientation of the hydroxyl groups. The hydroxyl groups affect solubility both by forming hydrogen bonds with the solvent and by reducing the hydrophobic area of the steroid nucleus. The enthalpic H0 and entropic S0 contributions to 0 associated with the dissolution process were obtained from the temperature dependence of the solubilities. A qualitative interpretation of the thermodynamic parameters in relation to bile acid structure is also presented.  相似文献   

9.
In addition to the know steroid sapogenin (25S)-ruscogenin (I), three new glycosides have been isolated from the leaves ofNolina microcarpa S. Wats. (family Dracaenacea), and the following structures are suggested for them: (25S)-spirost-5-ene-1,3-diol 1-O--D-fucopyranoside (nolinospiroside C, II), (25S)-furost-5-ene-1,3,22,26-tetraol 1-O--D-fucopyranoside (nolinofuroside A, III), and (25S)-furost-5-ene-1, 3, 22, 26-tetraol 1-O--D-fucopyranoside 26-O--D-glucopyranoside (nolinofuroside C, V).M. V. Frunze Simferopol' State University. Institute of Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 672–678, September–October, 1991.  相似文献   

10.
The oxime of 5-pregnen-3-ol-20-one reacts with acetylene in the KOH-DMSO system to form a mixture of products containing 3-vinyloxy-17-(1-vinyl-2-pyrrolyl)-5-androstene as the major product (63% yield) and also the O-vinyloxime of 3-vinyloxy-5-pregnen-20-one (10%), 3-vinyloxy-17- and 3-vinyloxy-17-5-pregnen-20-one (25%, 1:4 ratio).  相似文献   

11.
A survey of top soil environmental radioactivity in Akwa Ibom State of Nigeria has bean investigated. The results vary considerably from one environment to another ranging between a minimum of 161 mBq·g–1 and a maximum value of 648 mBq·g–1 -activity. The work reveals that hospitals and health centres lead in top soil radioactivity with the highest mean values of (378 mBq·g–1) and (294 mBq·g–1) followed closely by industrial areas with mean values of (372 mBq·g–1) and (283 mBq· g–1) trailing beaches and recreation centres having average values of (364 mBq·g–1) and (273 mBq·g–1). Lower levels of top soil radioactivity were observed mostly in environments with high level human interaction activity such as schools, offices, environments and recreation centres. An overall top soil mean of 342 mBq·g–1 -activity, 271 mBq·g–1 -activity and 71 mBq·g–1 -activity were observed in the State.  相似文献   

12.
The interaction of 3,5-dichloro-2-pyridylhydrazine with ,-unsaturated carbonyl compounds leads to 1-(3,5-dichloro-2-pyridyl)-3,5-disubstituted 2-pyrazolines. It was shown that N-(3,5-dichloro-2-pyridyl)hydrazones of the corresponding aldehydes and ketones are formed as intermediates. Condensation of the hydrazine mentioned above with ,-diketones gives 1,3,5-trisubstituted pyrazoles, but with acetoacetic ester a 1,3-disubstituted pyrazol-5-one containing a 3,5-dichloropyridyl residue is obtained.  相似文献   

13.
Steroid compounds from the Pacific starfish Lysastrosoma anthosticta   总被引:1,自引:0,他引:1  
Two new steroid compounds, 3,6-dihydroxy-5-cholesta-9(11),24-dien-23-one 3-sulfate and 3,6-dihydroxy-5-cholest-9(11)-en-23-one 3-sulfate, were isolated from the Pacific starfish Lysastrosoma anthosticta as the corresponding sodium salts and identified. Two previously known glycosides of 24(S)-5-cholestane-3,6,8,15,24-pentol were also isolated and identified as sodium 24-O--d-glucopyranoside 6"-sulfate (pycnopodioside C) and sodium 24-O--d-xylopyranoside 4"-sulfate (luridoside A).  相似文献   

14.
60Co -ray radiolysis of cholesterol /3-hydroxy-5-cholestene/ /I/ in the two-phase system /water-ethyl acetate/ and in the presence of air has been studied using TLC and GC methods. The following products were observed in the irradiated mixture: 3, 7-dihydroxy-5-cholestene /II/, G O. 36, 3-hydroxy-7-keto-5-cholestene /III/, G 1.48, 3-hydroxy-7-keto-5-cholestane /IV/, G 0.22, 3,5,6-trihydroxy-5-cholestane /V/, G 0.83, 5,6-epoxy-3-hydroxy-5-cholestane /VIa/, G 0.26, 5,6-epoxy-3-hydroxy-5-cholestane /VIb/, G 0.24, and 2, 3-dihydroxy-5-cholestene /VII/, G 0.22. The dose dependence of the formation of these products shows that the cholesterol derivatives substituted in the position 7 /II–IV/ are formed from a common precursor — the radical Ia. On the other hand, the products of the 5–C=C double bond reactions /V and VI/ are formed independently. Also the product VII is formed independently. A reaction scheme that is in agreement with these results is proposed.  相似文献   

15.
Furan analogs of chalcones are condensed with phenylhydrazine to give a number of 2-pyrazolines hitherto not described in the literature. It is shown that in , -unsaturated ketones, a nitro-group in the nucleus and remote from the carbonyl group makes cyclization to the corresponding 2-pyrazolines more difficult than does one adjacent to the carbonyl.  相似文献   

16.
The previously known triterpenoid 3-O--L-arabinopyranosides of oleanolic and echinocystic acids and hederagenin, 3-O--D-glucopyranosyl-(12)-O--L-arabinopyranosides of oleanolic acid and hederagenin, in addition to 28-O--L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl ethers of the 3-O--L-arabinopyranoside of hederagenin, and 3-O--D-glucopyranosyl-(12)-O--L-arabinopyranosides of oleanolic acid and hederagenin, respectively, are isolated from leaves ofFatsia japonica(Araliaceae). The structures of the glycosides are confirmed by chemical methods and 13 C NMR spectroscopy  相似文献   

17.
Cyclosiversigenin 6-O--L-rhamnopyranoside and 6-O--D-glucopyranoside were isolated fromAstragalus coluteocarpusBoiss. (Leguminosae) andAstragalus dissectusB. Fedtsch. et N. Ivanova, respectively. Cyclosiversigenin 5-O--L-rhamnopyranoside was shown to be an artifact forAstragalus coluteocarpus.Thus, the cyclosiversigenin 6-O--D-glucopyranoside that was isolated from certainAstragalusspecies is hypothesized also to be an artifact. Glycosylation of the 6 -hydroxyl group of cycloartanes by D-glucose and D-xylose, in contrast with other substituents, does not change the low-field position of the PMR signal of the 4-CH 3 group (1.65 2.01 ppm) that is caused by the influence of deuteropyridine directly on the 6 -hydroxyl. Obviously one of the hydroxyls of the -D-glucopyranoside or -D-xylopyranoside residues has the same effect in this instance.  相似文献   

18.
Five new sulfated derivatives of sokotrasterol and halistanol have been obtained: 24-nor-5-cholane-2,3,6,23-tetraol 2,3,6-tri(sodium sulfate); 24-nor-5-cholane-2,3,6,23-tetraol 2,3,6-tri(sodium sulfate) 23-palmitate; 24,25-dimethyl-5-cholestane-2,3,6-triol 3-(sodium sulfate); 24,25-dimethyl-5-cholestane-2,3,6-triol 6-(sodium sulfate); and 24,25-dimethyl-5-cholestane-2,3,6-triol 2,6-di(sodium sulfate). The inhibiting and membranolytic properties of the polysulfated steroids from sponges and their derivatives have been studied. It has been shown that physiological activity in this series of compounds depends on biphilicity.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 441–445, July–August, 1986.  相似文献   

19.
Conclusions The theory was expressed that the acetolysis of 3,4-caranediol monotosylate proceeds via the intermediate formation of the protonated form of -3,4-epoxycarane and a mechanism was proposed for rearrangement of the carane structure with 1,3-trans-annular cyclopropyl involvement in the acetolysis of -3,4-epoxycarane and 3,4-caranediol monotosylate, and also the hydration of -3,4-epoxycarane.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2778–2780, December, 1980.  相似文献   

20.
The solubility of nimodipine was measured in aqueous solutions of the following cyclodextrins: -cyclodextrin (-CD), hydroxypropyl--CD (HP--CD), -cyclodextrin (-CD), random substituted methyl--CD (M--CD), three hydroxypropyl--CDs (HP--CD) with mutually different average degree of substitution, and hydroxypropyl--cyclodextrin (HP--CD). From the determined linear solubility diagrams the values of the binding constant K11 of the inclusion complexes of nimodipine with the respective CDs were evaluated. The -CDs efficiently solubilized sparingly soluble nimodipine, the highest value of K11 was found for M--CD (1680 M-1), followed by -CD (550 M-1) and HP--CDs, where the higher degree of substitution lowered K11. Only slight solubilization of nimodipine was observed in the solutions of the -CDs and HP--CD.  相似文献   

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