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Published on: November 17, 2011
2'-Methyl-pyrazolo[4',3':16,17]androst-5-en-3β-ol
Hu-Ling Zheng1, Peng Xia, Ying Chen
1Department of Medicinal Chemistry, School of Pharmacy, Fudan University, 138 Yixueyuan Road Shanghai 200032, People's Republic of China.
Summary
This study details the complex fused ring structure of a novel organic compound, C(21)H(30)N(2)O. The research elucidates its specific molecular conformations and intermolecular hydrogen bonding, crucial for crystal stability.
Area of Science:
- Organic Chemistry
- Crystallography
- Molecular Structure
Background:
- Understanding the three-dimensional arrangement of atoms in organic molecules is fundamental.
- Fused ring systems present unique conformational challenges and properties.
- Pyrazole moieties are common in pharmaceuticals and materials science.
Purpose of the Study:
- To determine the precise crystal structure and molecular conformation of the title compound, C(21)H(30)N(2)O.
- To investigate the role of intermolecular interactions in stabilizing the crystal lattice.
- To confirm the absolute structure through analysis of starting materials.
Main Methods:
- Single-crystal X-ray diffraction was employed to analyze the compound's structure.
- Conformational analysis of the fused ring system was performed.
- Hydrogen bonding interactions were identified and quantified.
Main Results:
- The compound features five fused rings with distinct conformations: chair (A and C), 8β,9α-half-chair (B), and 14α-envelope (D).
- The pyrazole ring was found to be planar.
- Intermolecular O-H⋯N hydrogen bonds (1.88(5) Å) were observed, contributing to crystal stability.
Conclusions:
- The study provides a detailed structural characterization of a complex organic molecule.
- The identified hydrogen bonding network is key to the compound's solid-state organization.
- The absolute structure determination offers insights for synthetic modifications and applications.
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