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Updated: Jun 1, 2026
07:47
Anti-virulent Disruption of Pathogenic Biofilms using Engineered Quorum-quenching Lactonases
Published on: January 1, 2016
Xyloccensin e
Summary
Phragmalin triacetate, a limonoid from X. rumphii, features an intricate eight-ring structure. Its complex stereochemistry and crystal packing were elucidated, revealing specific ring conformations and intermolecular interactions.
Area of Science:
- Natural Product Chemistry
- Organic Chemistry
- Crystallography
Background:
- Xylocarpus rumphii is a source of complex natural products.
- Limonoids, such as phragmalin derivatives, exhibit diverse biological activities.
- Structural elucidation of novel compounds is crucial for understanding their properties.
Purpose of the Study:
- To determine the detailed molecular structure of phragmalin triacetate.
- To analyze the conformational aspects and stereochemistry of the compound.
- To investigate the crystal packing and intermolecular interactions.
Main Methods:
- Extraction and isolation of phragmalin triacetate from X. rumphii.
- Single-crystal X-ray diffraction for structural determination.
- Conformational analysis based on crystallographic data.
Main Results:
- The structure of phragmalin triacetate (C35H42O14) was determined, revealing an eight-ring system with a bridged orthoacetate group.
- Specific conformations were assigned to each ring: distorted envelope for A(1), A(2), and G; chair for E; twisted-boat for B and C; half-chair for the lactone ring; and planar for the furan ring.
- Cis-fusion was observed in multiple ring junctions (A(1)/B, A(2)/B, B/C, C/D, C/G).
- Acetoxy groups and the furan ring were found in equatorial positions.
- Porous crystal packing with voids and weak C-H⋯O interactions was identified.
- Absolute configuration was assigned using literature data.
Conclusions:
- The study provides a comprehensive structural and conformational analysis of phragmalin triacetate.
- The detailed structural information aids in understanding the structure-activity relationships of phragmalin-type limonoids.
- The findings contribute to the knowledge of natural product chemistry and crystallography.
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