Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 52 (1996), S. 212-215 
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: In the title compound, methyl (22S)-11β-hydroxy-16α,17α-[(methoxy)(methyl)methylenedioxypregna-1,4-diene-3,20-dione-21-acetate, C26H34O8, part of the orthoacetate group forms the dioxalane ring (E) fused with the steroid skeleton at the C16 and C17 atoms. Ring A is planar, rings B and C adopt chair conformations, while rings D and E have conformations midway between half-chair and envelope. Intermolecular O11—H...O3 hydrogen bonds are formed. The new chiral center at atom C22 of the dioxolane ring has an S configuration and the conformation of the ring, closed at C22, is comparable with the conformations found for the (22R) diastereoisomers of similar compounds.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 52 (1996), S. 2288-2290 
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical crystallography 25 (1995), S. 677-681 
    ISSN: 1572-8854
    Keywords: Steroids ; pregnadiene ; hydroxyprednisolone acetals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract The crystal and molecular structures of two synthetic corticosteroid diastereoisomers were determined by X-ray diffraction methods. (22R)-21-acetoxy-16α,17α-furfurylidenedioxy-11β-hydroxy-pregna-1,4-diene-3,20-dione, C28H32O8, crystallized in the orthorhombic system, space group P212121,a=6.346(1),b=14.106(2),c=27.901(3) Å, andZ=4. (22S)-21-acetoxy-16α, 17α-furfurylidenedioxy-11β-hydroxy-5 pregna-1,4-diene-3,20-dione ethanolate, C28H32O8 ·C2H5OH, crystallized in the monoclinic system, space group C2,a=20.382(5),b=8.331(1),c=17.346(4)Å, β=103.43(2)°, andZ=4. A change of configuration at the C(22) chirality center has influence on the remote parts of the molecules. The long-range effects appear in the ability to form intermolecular hydrogen bonds by different atoms and consequently in the solvation of the (S) diastereoisomer.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 9 (1989), S. 447-451 
    ISSN: 0138-4988
    Keywords: Life Sciences ; Life Sciences (general)
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Notes: The new synthesis of 9α-hydroxy-4-androsten-3,17-dione from hydrocortisone is described. The six-step reaction sequence involved degradation of the side chain, dehydration, ketals formation, reduction of the α-epoxide to 9α-hydroxyderivative and ketal groups cleavage. The overall yield is about 12%. Physico-chemical data of two new compounds were determined.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...