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1.
A new and more effective sequence of reactions is proposed for the production of 16,17-isopropylidenedioxy-5-pregnane-3,21-diol-20-one. It uses methods previously unused for 5-H-steroids and involves 21-hydroxylation of 16,17-epoxy-5-pregnan-3-ol-20-one with diacetoxyiodobenzene and cis-opening of the obtained 21-hydroxy-16,17-epoxy-5-pregnane-3,21-diol-20-one by acetic acid in the presence of epoxycarbonylhydrazine, followed by condensation of the obtained product with acetone.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1185–1188, May, 1991.  相似文献   

2.
In addition to the known 2-deoxy--ecdysone, 2-deoxyecdysterone, 2-deoxy--ecdysone-22-O-acetate, ecdysterone, integristerone A, and sileneoside A, B, and C, the new ecdysteroid 2-deoxyecdysterone 20,20-monoacetonide has been isolated from the roots of the plantSilene brahuica Boiss.Institute of Chemistry of Plant Substances Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 241–244, March–April, 1991.  相似文献   

3.
A new ecdysteroid has been isolated from the epigeal organs ofSilene brahuica Boiss. — 2-deoxy--ecdysone 3-O--D-glucopyranoside (I), C33H54O10, mp 195–196°C, [] D 20 + 44.4° (methanol). The enzymatic hydrolysis of (I) led to 2-deoxy--ecdysone. Details of the IR, UV, mass, and1H and13C NMR spectra of all the compounds are given.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 323–326, May–June, 1986.  相似文献   

4.
The isolation of four triterpene glycosides from the roots of the dahurian anemonePulsatilla dahurica (Fisch. ex DC) Spreng, is described together with their identification, on the basis of chemical transformations, spectral characteristics, and literature analogies, as hederagenin 3-O--L-arabinoside, hederagenin 3-O-[O--D-glucopyranosyl-(12)--L-arabinopyranoside], hederagenin 3-O--L-arabinopyranoside 28-O-[O--L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranoside], and hederagenin 3-O-[O--D-glucopyranosyl-(14)--L-arabinopyranoside] 28-O-[O--L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranoside].Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, Russian Academy of Sciences, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, Nos. 3,4, pp. 349–356, May–August, 1992.  相似文献   

5.
Zusammenfassung Ausgehend von der KL-Ionisation wurden die K -Satelliten(, , 3, 3, 4) der Elemente Z=8 bis Z=12 den entsprechenden Übergängen zugeordnet. Die Berechnung der Übergänge wurde nach der Z-Dependence-Theorie bis einschließlich zweiter Näherung durchgeführt.
Interpretation of the K -satellites of the light elements
Starting from the KL-ionisation the K -satellites(, , 3, 3, 4) of the elements Z=8 to Z=12 have been assigned to the corresponding transitions. The transitions have been calculated by the Z-dependence-theory including the second approximation.

Résumé Les satellites K (, , 3,3, 4) des éléments Z= 8 à Z=12 ont été attribués aux transitions correspondantes à partir de l'ionisation KL. Les transitions ont été calculées par la théorie dépendant de Z en tenant compte de l'approximation seconde.


Herrn Prof. Timm in dankbarer Würdigung der Hilfen, die die BASF für den Aufbau unserer theoretisch-chemischen Arbeitsgruppe geleistet hat, zum 60. Geburtstag gewidmet.

Der Deutschen Forschungsgemeinschaft dankt D. H. für die finanzielle Unterstützung, die die Dunchführung dieser Arbeit wesentlich erleichterte.  相似文献   

6.
The reaction of hydrazides of adenylyl- or hypoxanthinyl-9-alkylcarboxylic acids with sodium nitrite in acid media gives reactive azides of purinyl-9-alkylcarboxylic acids which condense with ()-aminocarboxylic and ,-diaminocarboxylic acids to give N(N)-(adenylyl-9-alkanoyl) aminocarboxylic, N-(adenylyl-9-)- and N-(hypoxanthinyl-9-alkanoyl)-,-diaminocarboxylic acids. The deamination of N-(adenyl-yl-9-alkanoyl)aminocarboxylic acids gives N-(hypoxanthinyl-9-alkanoyl)aminocarboxylic acids.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 126–130, January, 1985.  相似文献   

7.
The characteristics of crystallization, melting and spherulitic growth of a random propylene copolymer (PRC) containing small amount of ethylene were studied in the presence of a selective -nucleating agent (calcium pimelate). It was established that the products of isothermal and non-isothermal crystallization are very rich in -modification but have mixed polymorphic composition. The formation of -modification may be attributed to -transition on the surface of growing -spherulites resulting in -twin-spherulites. During melting of PRC of -modification, the characteristics observed with -nucleated propylene homopolymers, namely, a -recrystallization of recooled samples and separated melting of non-recooled samples (i.e. the melting memory effect), as well as a -recrystallization leading to a perfection of the structure within the -modification, are also demonstrated. The disturbance of regularity of the polymer chain highly reduces the tendency to -crystallization. In contrast to the observations with propylene homopolymers, the growth rate of -modification (G ) is higher than that of -modification (G ) and no critical crossover temperature can be found (T()=413 K) below whichG >G . The experimental results show that a partial disturbance of chain regularity by incorporation of comonomer units considerably reduces the tendency to -crystallization.This research was supported by the National Scientific Research Fund (OTKA), the author is grateful for it. Thanks are due to Professor Géza Bodor for his help in X-ray diffractometric investigations and to Ms. Tünde Lócska for her prudential technical assistance in the optical experiments.  相似文献   

8.
The following groups of title substances according to general formula I where prepared: substituted , -diphenyl-2-thenyl-derivatives (mainly of heterocyclic secondary amines), chlorinated -phenyl--(2-thienyl)-4-pyridinemethanoles and substituted (mainly chlorinated) tri- and tetraphenylmethanes.  相似文献   

9.
Cyclohexene transformation was used as test reaction to study the effect of lanthanum exchange on the catalytic behavior of HY zeolite cracking catalysts. Lanthanum has an overall positive effect increasing both acitivity and stability of HY zeolite and maximum selectivity towards isomerization products is obtained at higher conversion.
HY. , , HY. .
  相似文献   

10.
Summary The dynamic mechanical properties of nylon 66 films and fibers have been examined, as a function of annealing and drawing, with a Vibron viscoelastometer. It is found that the transition is little affected by annealing treatments, but increase in orientation causes the transition to move to a higher temperature. Experiments, with X-ray diffraction of samples at elevated temperatures, lead to the conclusion that the triclinic to hexagonal phase change does not contribute significantly to the transition. Samples cut parallel and perpendicular to the drawing direction of nylon 66 film, have been used to show that the curves of dynamic tensile modulus versus temperature, for the parallel and perpendicular directions, cross in the neighborhood of the transition. This observation is discussed in relation to the suggestion that the transition is the glass transition in nylon 66.
Zusammenfassung Die dynamisch-mechanischen Eigenschaften von Filmen und Fasern aus Nylon 66 wurden als Funktion der Temperung und Verstreckung mit einem Virbon-Viskoelastometer untersucht. Die -Umwandlung wird wenig durch die Temperung beeinflußt, aber erhöhte Orientierung läßt siezu höheren Temperaturen verlagern. Messungen der Röntgenstreuung bei erhöhten Temperaturen führen zu dem Schluß, daß der Übergang triklin/hexagonal nicht wesentlich zu der -Umwandlung beiträgt. Proben aus verstrecktem Nylon-66-Film, parallel und senkrecht zur Streckrichtung geschnitten, zeigen, daß die Kurven des dynamischenE-Moduls gegen die Temperatur für beide Orientierungen sich in der Nachbarschaft der -Umwandlung überkreuzen. Diese Beobachtung wird hinsichtlich der Vermutung diskutiert, daß die -Umwandlung den Glasübergang in Nylon 66 darstellt.


With 5 figures and 2 tables  相似文献   

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