Results 131 to 140 of about 514 (159)
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The structure of ‘cholestane-3,4,6-trione’
J. Chem. Soc., Perkin Trans. 1, 1972The compound described as ‘cholestane-3,4,6-trione’ by Windaus and Kuhr has been shown to be the 3-ethyl ether of the corresponding dienol. Although relatively stable to acid, the enol ether may be hydrolysed to yield the triketone, a mixture of two stable tautomers, which may be separated readily by fractional crystallisation.
J T, Pinhey, E, Rizzardo
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A convenient synthesis of 5β-cholestan-26-oic and 5β-cholestan-26,27-dioic acids
Steroids, 2000A new method for the preparation of 5beta-cholestan-26-oic acids 7 and their analogs is described. The key steps in the synthesis are: iodination of bis- and tris-formyloxy-5beta-cholan-24-ols 3; nucleophilic substitution of iodides 4 with diethyl sodiomalonate; complete alkaline hydrolysis of esters 5; and subsequent decarboxylation of geminal diacids
I, Starchenkov +4 more
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ChemInform Abstract: 2‐HETERO‐CHOLESTANE
Chemischer Informationsdienst. Organische Chemie, 1971AbstractDas Cholestenon (I) gibt bei Reaktion mit K‐permanganat/Na‐perjodat die Dicarbonsäure (II), deren Dimethylester durch Reduktion mit Li‐alanat in das Diol (IIIa) übergeführt wird.
Y. KASHMAN, E. D. KAUFMAN
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Steroids. Part XXXVIII. 5-Chloro-5α-cholestane
J. Chem. Soc., Perkin Trans. 1, 1975The formation of 5-chloro-5α-cholestane from cholest-5-ene and hydrogen chloride in ether–ethanol at 25 °C appears to be accompanied by production of an unidentified chloro-5ξ-cholestane; 5-chloro-5β-cholestane could not be isolated.
C W, Shoppee, R D, Lundberg
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Homo‐Cholestane Glycosides from Solanum aethiopicum
ChemInform, 2003AbstractFor Abstract see ChemInform Abstract in Full Text.
Chie Tagawa +4 more
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Synthese der 2,5‐Diole des A‐nor‐5α‐Cholestans und A‐nor‐5β‐Cholestans
Helvetica Chimica Acta, 1967AbstractTreatment of A‐nor‐Δ3(5)‐cholestene‐2‐one (1) with alkaline hydrogen peroxide gave 3β,5‐epoxy‐A‐nor‐cholestane‐2‐one (2) and the epoxylactone 3 (BAEYER‐VILLIGER reaction). LiAlH4‐reduction of 2 yielded A‐nor‐5β‐cholestane‐2β,5‐diol(4) (main product) and A‐nor‐5β‐cholestane‐2α,5‐diol (5).
R. Heckendorn, Ch. Tamm
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Two‐photon‐induced fluorescence of cholestane
Biospectroscopy, 1996Cholestane is a fully saturated alkane with a structure analogous to cholesterol. We observed fluorescence emission from cholestane with a maximum near 235 nm when excited with picosecond laser pulses at 298 nm. The emission intensity of cholestane was found to depend on the square of the laser power, indicating the biphotonic process of two-photon ...
Rezik A. Agbaria +3 more
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Brassinosteroids with a cholestane side chain
Collection of Czechoslovak Chemical Communications, 1986The synthesis of 2α,3α-dihydroxy-B-homo-7-oxa-cholestan-6-one (VI), 2β,3β-dihydroxy-B-homo-7-oxa-5α-cholestan-6-one (VIII) and 2α,3α-dihydroxy-B-homo-6-oxa-5α-cholestan-7-one (XI) is described. The activity of these brassinosteroids in the bean second internode bioassay is lower than the activity of 24-epibrassinolide (XXI).
Ladislav Kohout, Miroslav Strnad
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1‐Keto‐cholestan. Steroide, 8. Mitteilung
Helvetica Chimica Acta, 1954AbstractAusgehend von Cholesten‐(1)‐on‐(3) (IV) wurden 1‐Keto‐cholestan (XX), 1 α‐Oxy‐cholestan (XVIII) und 1 β‐Oxy‐cholestan (XXI) auf eindeutigem Wege in Kristallen bereitet.
P. Striebel, Ch. Tamm
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Australian Journal of Chemistry, 1983
Chlorination of Sa- and 5ß-cholestan-3-one (l) and (7) proceeds sequentially to give the a-monochloro (2) and (8), a,a-dichloro (3) and (9), and a, a, a'-trichloro (4) and (10) derivatives; the nature of the product mainly depends on the reaction conditions.
M Kuniyoshi, Y Satoh
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Chlorination of Sa- and 5ß-cholestan-3-one (l) and (7) proceeds sequentially to give the a-monochloro (2) and (8), a,a-dichloro (3) and (9), and a, a, a'-trichloro (4) and (10) derivatives; the nature of the product mainly depends on the reaction conditions.
M Kuniyoshi, Y Satoh
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