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Absolute configuration of 3?-acet-oxy-olean-11,12-aziridin-28,13-?-olide.

ABSTRACT: The title compound, C(32)H(49)NO(4), has been isolated from the dichloro-methane extract of the stem bark of Garcinia atroviridis Griff. ex T. Anders. Rings A and B, B and C, and C and D are trans-fused, whereas rings D and E are cis-fused. Rings A, B, C and E have slightly distorted chair conformations, while ring D is most heavily distorted towards a half-chair conformation owing to the strain induced by the lactonization. The ester group attached to ring A is in an equatorial position.

SUBMITTER: Tan WN

PROVIDER: S-EPMC3089217 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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Absolute configuration of 3β-acet-oxy-olean-11,12-aziridin-28,13-β-olide.

Tan Wen Nee WN Wong Keng Chong KC Khairuddean Melati M Hemamalini Madhukar M Fun Hoong-Kun HK

Acta crystallographica. Section E, Structure reports online 20110429 Pt 5

The title compound, C(32)H(49)NO(4), has been isolated from the dichloro-methane extract of the stem bark of Garcinia atroviridis Griff. ex T. Anders. Rings A and B, B and C, and C and D are trans-fused, whereas rings D and E are cis-fused. Rings A, B, C and E have slightly distorted chair conformations, while ring D is most heavily distorted towards a half-chair conformation owing to the strain induced by the lactonization. The ester group attached to ring A is in an equatorial position. ...[more]

PMID: 21754518

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