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Updated: Jun 19, 2026
Green Synthesis, Characterization, Encapsulation, and Measurement of the Release Potential of Novel Alkali Lignin Micro-/Submicron Particles
Published on: March 1, 2024
Efficient and practical synthesis of L-hamamelose
Won Hee Kim1, Jin-Ah Kang, Hyung-Rock Lee
1Laboratory of Medicinal Chemistry, College of Pharmacy and Research Institute for Drug Development, Pusan National University, Busan 609-735, Republic of Korea.
Researchers developed an efficient synthesis for L-hamamelose from D-ribose. This chiral building block is crucial for creating enantiopure compounds, with the new method achieving a 42% yield over six steps.
Area of Science:
- Organic Synthesis
- Carbohydrate Chemistry
- Stereoselective Reactions
Background:
- L-hamamelose is a valuable chiral building block for enantiopure compound synthesis.
- Efficient and stereoselective synthetic routes are essential for accessing such compounds.
Purpose of the Study:
- To establish an efficient synthetic route for L-hamamelose starting from D-ribose.
- To explore stereoselective reactions for controlled synthesis.
Main Methods:
- A six-step synthesis commencing with D-ribose.
- Key reactions included a stereoselective Grignard reaction and a stereoselective crossed aldol reaction.
- Controlled oxidative cleavage of a vinyl diol intermediate using osmium tetroxide and sodium periodate.
Main Results:
- Successful synthesis of L-hamamelose achieved with a 42% overall yield.
- Demonstrated controlled oxidative cleavage, avoiding over-oxidation of the intermediate lactol.
- Proposed a plausible mechanism for the stereoselective crossed aldol reaction.
Conclusions:
- An efficient and stereoselective synthetic route to L-hamamelose has been developed.
- The stability of the lactol form prevented undesired over-oxidation.
- L-hamamelose is confirmed as a key chiral synthon for enantiopure compound preparation.
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