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1.
The circular dichroism method has been used to establish the stereochemical features of the structure of the withasteroids. The 22S-configuration of the asymmetric center has been confirmed for physangulide. The 22R-configuration has been confirmed for 14α-hydroxyixocarpanolide, vamonolide, ixocarpanolide, 24,25-epoxywithanolide D, and withanolide T. On the basis of changes in the circular dichroism spectra in acid and alkaline media it is suggested that in compounds having a 4β-hydroxy-1-oxo-5β,6β-epoxy-2,3-ene grouping the Δ2,3 bond disappears, while in compounds having a 5α-hydroxy-1-oxo-6α,7α-epoxy-2,3-ene grouping dehydration takes place at C-4-C-5. These characteristics can be used in the identification of the withasteroids. The isolation of withanolide T from the leaves ofPhysalis angulata L. is described and its spectral characteristics are given. Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 371–376, May–June, 1990.  相似文献   

2.
The circular dichroism method has been used to establish the stereochemical features of the structure of the withasteroids. The 22S-configuration of the asymmetric center has been confirmed for physangulide. The 22R-configuration has been confirmed for 14-hydroxyixocarpanolide, vamonolide, ixocarpanolide, 24,25-epoxywithanolide D, and withanolide T. On the basis of changes in the circular dichroism spectra in acid and alkaline media it is suggested that in compounds having a 4-hydroxy-1-oxo-5,6-epoxy-2,3-ene grouping the 2,3 bond disappears, while in compounds having a 5-hydroxy-1-oxo-6,7-epoxy-2,3-ene grouping dehydration takes place at C-4-C-5. These characteristics can be used in the identification of the withasteroids. The isolation of withanolide T from the leaves ofPhysalis angulata L. is described and its spectral characteristics are given.Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 371–376, May–June, 1990.  相似文献   

3.
A new withasteroid — physangulide — has been isolated from the leaves ofPhysalis angulata L. It has been shown that physangulide is the first natural 22S-withanolide. Its structure has been determined as 3β,4β,20,24,25-pentahydroxy-1-oxo-5β,6β-epoxy-20R,22S,24S,25R-withanolide. Its1H and13C NMR spectra, confirming this interpretation, are given. Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 366–371, May–June, 1990.  相似文献   

4.
Two new withasteroid have been isolated fromPhysalis angulata L. — 14α-hydroxyixocarpanolide and 24,25-epoxywithanolide D. 14α-hydroxyixocarpanolide — C28H40O7, mp 245–250°C (from methanol), [α] D 20 +29±2° (chloroform). 24,25-Epoxywithanolide D — C28H38O7, mp 257–261°C (from methanol, [α] D 20 +23±2° (chloroform). On the basis of its UV, IR, CD, mass, and1H and13C NMR spectra the structure of 5α,14α,20R-trihydroxy-1-oxo-6α,7α-epoxy-22R-2itha-2-enolide is suggested for 14α-hydroxyixocarpanolide. On the basis of spectral characteristics and the preparation of 4β-acetoxy and 4-oxo derivatives of 24,25-epoxywithanolide D, the structure of 4β,20R-dihydroxy-1-oxo-5β,6β;24S,25S-diepoxy-22R-witha-2-enolide is proposed for it.  相似文献   

5.
Two withanolides have been isolated from the epigeal part ofPhysalis viscosa L. One of them with the compositions C28H38O8 has been identified as 4-hydroxy-withanolide E, and for the second, which has been called physanolide, the structure of 14,17,20R-trihydroxy-1,4-dioxo-22R-witha-5,24-dienolide has been proposed on the basis of its UV, IR, PMR, and mass spectra, and also the results of a partial synthesis of 14-hydroxyandrost-5-ene-1,4,17-trione, obtained by its oxidation.Institute of the Chemistry of Plant Substances, Academy of Sciences of Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 187–192, March–April, 1981.  相似文献   

6.
A new withanolide with the composition C28H38O7, which has been called withaphysanolide (I) has been obtained from a chloroform extract of an aqueous extract of the epigeal part ofPhysalis viscosa L. On the basis of a study of the UV, IR, PMR, and mass spectra of (I) and the products of the oxidation of its acetate (II) — a lactone C9H12O3 (III) and 4-acetoxy-5-hydroxy-1,17-dioxoandrosta-2,8(14)-diene (IV) — the structure of 4,5,17,20-tetrahydroxy-l-oxo-22R-witha-2,8(14),24-trienolide is suggested for (I).Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 214–217, March–April, 1980  相似文献   

7.
Summary 1. A new withanolide, which has been called physalactone, has been isolated fromPhysalis alkekengi L. growing in Turkmenia. It has the structure of 4,17,20(R)-trihydroxy-3-methoxy-1-oxo-5,6-epoxy-22R-witha-8(14), 24-dienolide.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 531–534, July–August, 1977.  相似文献   

8.
9.
A new withasteroid has been isolated fromPhysalis viscosa L. — 28-hydroxywithaphysanolide, with mp 234°C, composition C28H38O8. The13C NMR spectra of a number of withasteroids have been investigated. For 28-hydroxywithaphysanolide we propose the structure 4,14,17,20R,28-pentahydroxy-l-oxo-22R-witha-2,5,24-trienolide. The corresponding corrections have been made in the structural formulas of withaphysanolide and physalactone.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 197–207, March–April, 1984.  相似文献   

10.
The review gives a table of 47 withasteroids isolated from plants of the genusPhysalis. The biogenetic relationship between the different structures of the compounds is discussed on the basis of an analysis of literature material. An assignment of some C-methyl groups of the physalins is made.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 263–277, May–June, 1986.  相似文献   

11.
12.
Two new withanolides, namely (20S,22R)‐15α‐acetoxy‐5α‐chloro‐6β,14β‐dihydroxy‐1‐oxowitha‐2,24‐dienolide ( 1 ) and (22R)‐5β,6β : 14α,17 : 14β,26‐triepoxy‐2α‐ethoxy‐13,20,22‐trihydroxy‐1,15‐dioxo‐16α,24‐cyclo‐13,14‐secoergosta‐18,27‐dioic acid 18→20,27→22‐dilactone ( 2 ), along with six known compounds, physagulin B ( 3 ), withangulatin A ( 4 ), physalin I ( 5 ), withaminimin ( 6 ), physagulin J ( 7 ), and ergosta‐5,25‐diene‐3β,24ξ‐diol ( 8 ), were isolated from the whole plant of Physalis alkekengi var. francheti. Their structures were elucidated on the basis of spectroscopic analyses.  相似文献   

13.
Zusammenfassung Siedende Chrom(III)-sulfatlösungen lassen sich bei pH 3 nach Umsetzung mit einem bekannten ÄthylendiamintetraessigsÄure-(EDTA)-überschu\ und dessen Rücktitration bei 20 C mit 0,1 m Eisen(III)-chloridma\lösung bestimmen. Dabei dient das dunkelbraune Zersetzungsprodukt des Bindschedlers Grün als Redoxindicator. Der Bestimmungsbereich liegt für ein Titrationsvolumen von 100 ml unterhalb 20 mg Chrom.Die Simultanbestimmung von Eisen(III)- und Chrom(III)-Ionen ist möglich, wenn der soeben beschriebenen Chrombestimmung die Titration des dreiwertigen Eisens mit 0,1 m EDTA-Lösung gegen denselben Redoxindicator bei 20 C vorausgeht.Mitteilung VII dieser Reihe: diese Z. 149, 419 (1956).Der BASF danke ich für die freundliche Überlassung von Trilon BS. Herrn W. Johannsen, dem Laboratoriumsleiter der Metallhütte Mark A.G., bin ich für sein Interesse an dieser Arbeit zu Dank verpflichtet.  相似文献   

14.
15.
The1H and13C NMR spectra of two withasteroids isolated fromPhysalis ixocarpa Brot. have been studied in detail. Their spectral characteristics are discussed. A comparison of the results obtained has led to the identification of a withasteroid with the composition C28H40O8, mp 291–292°C (from methanol) as ixocarpalactone A, in spite of some difference in its physical constants. The other compound, with mp 252–253°C (from methanol), had the composition C28H40O6, [] D 20 +27±4°, is new and has been called ixocarpanolide. The structure of 5,20R-dihydroxy-1-oxo-6, 7-epoxy-22R-witha-2-enolide has been proposed for it.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 326–332, May–June, 1986.  相似文献   

16.
Two novel neophysalins, named physalin W ( 1 ) and physalin X ( 2 ), were isolated from the EtOH extract of the aerial parts of Physalis alkekengi L. var. franchetii (Solanaceae). Their structures were determined mainly by spectroscopic techniques including 2D‐NMR (HMBC, HSQC, 1H,1H‐COSY, NOESY) and MS experiments.  相似文献   

17.
Summary Cadmium and zinc can be determined in one solution in the following manner. The sample is adjusted to pH 9.4 with an ammonia-ammonium chloride buffer so that the total ammonia concentration is 0.01–0.03M. Zincon is added to attain a concentration of 0.06–0.18 mg/ml. The titration is performed photometrically at about 620 nm with EGTA as the titrant. The titration curve obtained shows two breaks which are related to the consecutive titration of cadmium and zinc. The influence of calcium impurities in the reagents used has been studied and a pre-titration method is proposed to deal with small calcium blanks. Calcium may also be added to the sample in order to obtain a titration curve which shows three breaks, which are related to the consecutive titration of cadmium, calcium, and zinc.
Zusammenfassung Cadmium und Zink lassen sich nebeneinander in einer Lösung bestimmen. Man bringt die Probe durch Zusatz von Ammoniak-Ammoniumchlorid-Puffer auf pH 9,4, so daß die totale Ammoniakkonzentration 0,01- bis 0,03-m ist. Pro ml werden 0,06 bis 0,18 mg Zincon zugesetzt, dann wird mit EGTA [Äthylenglykol-bis-(-aminoäthyläther)-N,N,N,N-tetraessigsäure] bei etwa 620 nm photometrisch titriert. Die Titrationskurve zeigt zwei Knickpunkte, die der aufeinanderfolgenden Titration von Cadmium und Zink entsprechen. Der Einfluß von Calcium-Verunreinigungen in den verwendeten Reagenzien wurde untersucht und eine Vortitration zur Bestimmung kleiner Calcium-Blindwerte vorgesehlagen. Man kann auch der Probe Calcium zusetzen und erhält dann eine Kurve mit drei Knickpunkten, entsprechend den aufeinanderfolgenden Titrationen von Cadmium, Calcium und Zink.

Résumé On peut doser le cadmium et le zinc sur une seule solution de la manière suivante. On ajuste le pH de l'échantillon à 9,4 par un tampon ammoniaque-chlorure d'ammonium de façon que la concentration totale en ammoniaque soit de 0,01–0,03M. On ajoute de la zincone jusqu'à l'obtention d'une concentration de 0,06–0,18 mg/ml. On effectue un dosage speetrophotométrique à 620 nm en utilisant l'EGTA comme agent titrant. La courbe de titrage montre deux points anguleux correspondant à la teneur en cadmium et en zinc. Après avoir étudié l'influence du calcium à l'état d'impuretés dans les réactifs utilisés, on propose une méthode de prétitrage pour faire les essais à blanc avec de petites quantités de calcium. On peut également ajouter du calcium à l'échantillon afin d'obtenir une courbe de titrage avec trois points anguleux relatifs aux titrages consécutifs du cadmium, du calcium et du zinc.


See reference 1 for paper VII of the series.

Dedicated to Prof.A. A. Benedetti- Pichler on the occasion of his 70th birthday.  相似文献   

18.
Chemistry of Natural Compounds - Total alkaloids (0.6%) were isolated from the aerial part of Physalis angulata. The known alkaloids cuscohygrine and tropine were identified for the first time in...  相似文献   

19.
20.
锦灯笼中无机元素含量测定   总被引:4,自引:0,他引:4  
采用ICP-AES法检测了要笼果实及其干燥宿萼中无机元素含量。结果表明,锦灯笼含有丰富的对人体有益的无机元素,具较高的营养价值。  相似文献   

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