Related Experiment Video
Updated: Jul 13, 2026
05:17
Functionalized Spirocyclic Heterocycle Synthesis and Cytotoxicity Assay
Published on: February 9, 2021
Synthesis of macrocyclic shellfish toxins containing spiroimine moieties
Patrick D O'Connor1, Margaret A Brimble
1Department of Chemistry, The University of Auckland, 23 Symonds Street, Auckland, New Zealand.
Natural Product Reports
|July 27, 2007
Summary
Dinoflagellate macrocyclic polyketides with cyclic imine units are potent shellfish toxins. Their synthesis focuses on the spiroimine group, a crucial pharmacophore for rapid toxin activity.
Area of Science:
- Marine natural products chemistry
- Organic synthesis
- Toxicology
Background:
- Dinoflagellates produce complex macrocyclic polyketides.
- Some of these compounds feature unique cyclic imine moieties.
- These toxins are known for their rapid action on shellfish.
Purpose of the Study:
- To provide an overview of dinoflagellate-derived macrocyclic polyketides.
- To discuss the synthesis of these molecules, focusing on the spiroimine unit.
- To highlight the role of the spiroimine as a key pharmacophore.
Main Methods:
- Review of existing literature on macrocyclic polyketide structures and activities.
- Analysis of total and partial synthetic strategies.
- Emphasis on synthetic routes to the spiroimine functionality.
Main Results:
- Detailed examination of the structural diversity of these compounds.
- Discussion of synthetic challenges and successes in constructing the macrocyclic framework.
- Identification of the spiroimine as a critical structural feature for biological activity.
Conclusions:
- Macrocyclic polyketides from dinoflagellates represent a significant class of marine toxins.
- The spiroimine functionality is central to their potent, fast-acting toxic effects.
- Synthetic efforts are crucial for understanding and potentially mitigating the impact of these toxins.
![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
Related Concept Videos
01:29Indirect-Acting Cholinergic Agonists: Chemistry and Structure-Activity Relationship
Indirect-acting cholinergic agonists are agents that interact with the acetylcholinesterase enzyme in the synaptic cleft, preventing the breakdown of acetylcholine into choline and acetate. Consequently, the concentration of acetylcholine in the synaptic cleft increases. These agonists can be classified into reversible and irreversible inhibitors based on their duration of action.
Reversible inhibitors display short to medium durations of action. Short-acting agents include simple alcohols with...
Reversible inhibitors display short to medium durations of action. Short-acting agents include simple alcohols with...
01:22Botulism
Botulism is a life-threatening neuroparalytic condition caused by botulinum neurotoxin, which is produced by the bacterium Clostridium botulinum, a Gram-positive, spore-forming, obligate anaerobe.In adults, the toxin enters the body in different ways: in foodborne botulism, the preformed toxin is absorbed in the intestine. In wound botulism, spores grow in injured tissue and release the toxin into the blood. Infant botulism differs mechanistically from adult forms. In infants, botulism commonly...
01:12Bacterial Toxins
Bacterial toxins are sophisticated virulence factors that enable pathogenic bacteria to interact with, invade, and damage host tissues. These toxins fall broadly into two types: protein exotoxins, which are secreted into the environment and target specific host receptors, and lipopolysaccharide endotoxins, which are structural components of the bacterial outer membrane released primarily during bacterial lysis or membrane shedding. Exotoxins generally act more selectively, binding to cell...
01:22Direct-Acting Cholinergic Agonists: Chemistry and Structure-Activity Relationship
Cholinergic agonists or cholinomimetics mimic the action of acetylcholine to stimulate the parasympathetic nervous system. They are categorized into direct-acting and indirect-acting agents. The direct-acting cholinergic drugs induce the parasympathetic response by directly binding to the muscarinic or nicotine receptors. In comparison, the indirect-acting cholinergic drugs prevent acetylcholine hydrolysis, indirectly contributing to the extended parasympathetic response.
The direct-acting...
The direct-acting...
01:29Cholinergic Antagonists: Chemistry and Structure-Activity Relationship
Cholinergic antagonists bind to cholinergic receptors and limit the effects of acetylcholine and other cholinergic agonists. Based on the specific cholinergic receptor affinity, these antagonists are classified as muscarinic or nicotinic. Anticholinergics interrupt parasympathetic innervations while sympathetic innervations remain uninterrupted. Muscarinic antagonists are also called 'muscarinic antagonists', 'antimuscarinics', or 'parasympatholytics'. Nicotinic antagonists are called...
01:26Synthesis of α-Substituted Carbonyl Compounds: The Stork Enamine Reaction
α-Substituted ketones or aldehydes can be synthesized from enamines by the Stork enamine reaction, named after its pioneer Gilbert Stork. Enamines are useful synthetic intermediates where the lone pair on nitrogen is in conjugation with the C=C bond. They resemble enolate ions, as the resonance forms of both species have a nucleophilic α carbon.