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Updated: Jul 10, 2026

Preparation of N-(2-alkoxyvinyl)sulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines
Published on: January 3, 2018
A concise and efficient synthesis of (-)-allosamizoline
Timothy J Donohoe1, Carla P Rosa
1Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford OX1 3TA, UK. timothy.donohoe@chem.ox.ac.uk
This study details a new synthesis of (-)-allosamizoline, a complex natural product. Key reactions like ring-closing metathesis and stereoselective radical addition were employed for efficient construction.
Area of Science:
- Organic Chemistry
- Natural Product Synthesis
Background:
- (-)-Allosamizoline is a natural product with potential biological activity.
- Efficient synthetic routes are crucial for accessing complex molecules like (-)-allosamizoline.
Purpose of the Study:
- To develop a regio- and stereocontrolled total synthesis of (-)-allosamizoline.
- To establish a concise and efficient synthetic strategy for this natural product.
Main Methods:
- The synthesis employed ring-closing metathesis to construct the cyclopentene core.
- Halocyclization was used to form the oxazoline ring.
- Stereoselective alkene radical addition and alkene isomerization installed the hydroxymethyl group.
Main Results:
- (-)-Allosamizoline was synthesized in a total of 13 steps.
- An overall yield of 22% was achieved for the total synthesis.
- Regio- and stereocontrol were maintained throughout the key transformations.
Conclusions:
- A practical and efficient total synthesis of (-)-allosamizoline was achieved.
- The described methodology provides a valuable route to this and related natural products.
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