Related Experiment Video
Updated: Jul 3, 2026
09:35
Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
[Study on the polyoxygenated cyclohexenes from Uvaria boniana]
1Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050.
Yao Xue Xue Bao = Acta Pharmaceutica Sinica
|April 10, 2002
Summary
Seven new cyclohexene compounds from Uvaria boniana stems were identified. While inactive themselves, a derivative (2a) showed significant cytotoxicity against human tumor cell lines.
Area of Science:
- Natural Product Chemistry
- Organic Chemistry
- Pharmacognosy
Context:
- The Annonaceae family, particularly the Uvaria genus, is a rich source of bioactive natural products.
- Uvaria boniana Finet. stems represent an underexplored botanical resource.
Purpose:
- To isolate and structurally elucidate new compounds from Uvaria boniana.
- To evaluate the in vitro cytotoxic potential of isolated compounds and their derivatives against human tumor cell lines.
Summary:
- Seven novel polyoxygenated cyclohexenes, uvaribonols A-G (1-7), were isolated from the ethanol extract of Uvaria boniana stems.
- Structural determination, including absolute configuration, was achieved using comprehensive spectral and chemical analyses.
- Initial cytotoxicity screening revealed that compounds 1-7 are inactive, but derivative 2a demonstrated significant activity.
Impact:
- Derivative 2a exhibits potent in vitro cytotoxicity against KB, Bel7402, and HCT-8 human cancer cell lines.
- The findings highlight the potential of Uvaria boniana derivatives as leads for anticancer drug development.
- This study expands the chemical diversity of cyclohexenes and provides a basis for further medicinal chemistry exploration.
More Related Videos
Related Concept Videos
02:28Cycloalkanes
Cycloalkanes are saturated cyclic hydrocarbons with carbon atoms arranged in the form of rings. They have two fewer hydrogen atoms than the corresponding acyclic alkane; therefore, their general formula is CnH2n. The structural formulas of cycloalkanes are simplified using the line-angle representation. The regular polygons are used to represent the cycloalkane rings, with each side representing a carbon-carbon bond.
The IUPAC nomenclature of cycloalkanes follows similar rules that apply to...
The IUPAC nomenclature of cycloalkanes follows similar rules that apply to...
02:30Stability of Substituted Cyclohexanes
This lesson discusses the stability of substituted cyclohexanes with a focus on energies of various conformers and the effect of 1,3-diaxial interactions.
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
01:17Thermal Electrocyclic Reactions: Stereochemistry
The stereochemistry of electrocyclic reactions is strongly influenced by the orbital symmetry of the polyene HOMO. Under thermal conditions, the reaction proceeds via the ground-state HOMO.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
01:28Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation
Unlike the easy catalytic hydrogenation of an alkene double bond, hydrogenation of a benzene double bond under similar reaction conditions does not take place easily. For example, in the reduction of stilbene, the benzene ring remains unaffected while the alkene bond gets reduced. Hydrogenation of an alkene double bond is exothermic and a favorable process. In contrast, to hydrogenate the first unsaturated bond of benzene, an energy input is needed; that is, the process is endothermic. This is...
01:18Frost Circles for Different Conjugated Systems
The inscribed polygon method is consistent with Hückel’s 4n + 2 rule and helps to learn whether the given cyclic compound is aromatic or not. The compound is stable and aromatic if every bonding molecular orbital (MO) is completely filled with a pair of electrons. However, if the non-bonding or antibonding orbitals are filled with electrons, the compound is unstable and not aromatic. Consider the Frost circle diagrams for cycloalkenes containing 4 to 8 carbons.
01:18Aromatic Hydrocarbon Cations: Structural Overview
Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group with both...
Removing one hydrogen from the intervening CH2 group with both...