Agnatasterone A and B, Unusual Pregnane Steroids Isolated from the North‐East Atlantic Sponge Axinella agnata
Abstract Two novel pregnatrienolones isolated in very small amounts from the North‐East‐Atlantic demosponge Axinella agnata (Tetractinomorpha, Axinellida) are unique in having C(2)C(3) (or C(3)C(4)), C(7)C(8), and C(16)C(17) bonds and a 12β‐OH group which, being strongly H‐bonded to a 20‐keto gr...
Published in: | Helvetica Chimica Acta |
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Main Authors: | , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Wiley
1988
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Subjects: | |
Online Access: | http://dx.doi.org/10.1002/hlca.19880710108 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fhlca.19880710108 https://onlinelibrary.wiley.com/doi/pdf/10.1002/hlca.19880710108 |
Summary: | Abstract Two novel pregnatrienolones isolated in very small amounts from the North‐East‐Atlantic demosponge Axinella agnata (Tetractinomorpha, Axinellida) are unique in having C(2)C(3) (or C(3)C(4)), C(7)C(8), and C(16)C(17) bonds and a 12β‐OH group which, being strongly H‐bonded to a 20‐keto group, resists acylation. 1 H‐ and 13 C‐NMR spectroscopy of the steroids and of products of their selective epoxidation or reduction allow us to propose the structures (+)‐12β‐hydroxy‐5α‐pregna‐2,7,16‐trien‐20‐one ( = agnatasterone A, (+)‐ 1 ), and (+)‐12β‐hydroxy‐5α‐pregna‐3,7,16‐trien‐20‐one ( = agnatasterone B. (+)‐ 5 ), for the two steroids with minimal recourse to model compounds. |
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