6α-Hy-droxy-5,6-dihydro-salviasperanol

Area of Science:

• Natural Products Chemistry
• Organic Chemistry
• Crystallography

Background:

• Premna obtusifolia is a plant species known for its diverse chemical constituents.
• Diterpenoids represent a significant class of natural products with various biological activities.
• Understanding the precise three-dimensional structure of natural compounds is crucial for structure-activity relationship studies.

Purpose of the Study:

• To determine the crystal structure of a specific diterpenoid isolated from Premna obtusifolia roots.
• To analyze the conformational characteristics of the diterpenoid's ring systems.
• To investigate the intermolecular interactions governing the crystal packing.

Main Methods:

• Single-crystal X-ray diffraction was employed to determine the molecular and crystal structure.
• Conformational analysis of the five- and six-membered rings was performed.
• Intermolecular interactions, including hydrogen bonding and van der Waals forces, were identified.

Main Results:

• The crystal structure of the C(20)H(28)O(4) diterpenoid was successfully resolved.
• The five-membered ring adopts a half-chair conformation.
• One six-membered ring exhibits a twisted-boat conformation, and the other adopts a half-boat conformation.
• Crystal packing is characterized by intermolecular O-H⋯O and weak C-H⋯O interactions, forming (001) sheets.

Conclusions:

• The study provides a detailed structural elucidation of a Premna obtusifolia diterpenoid.
• The identified conformations and crystal packing offer insights into the molecule's solid-state behavior.
• This structural information can serve as a foundation for further investigations into its chemical and biological properties.