272769-86-5

Upstream product

• 5447-02-9 3,4-dibenzyloxybenzaldehyde 
• 332900-03-5 [⁽¹³⁾CO]-1-[2,4,-bis(benzyloxy)-6-hydroxyphenyl]ethanone 
• 272769-84-3 (E)-1-[13C]-O-dibenzylcaffeic acid 
• 332900-02-4 [⁽¹³⁾CO]-1-[2,4,6-tris(benzyloxy)phenyl]ethanone 
• 59434-20-7 1,3,5-tri-O-benzylphloroglucinol 
• 272769-85-4 [13CO]-3,4,2',4',6'-pentabenzyloxychalcone 

Downstream Products

• 357409-17-7 C₆₁⁽¹³⁾CH₅₂O₁₃ 
• 357409-16-6 C₆₁⁽¹³⁾CH₅₂O₁₃ 
• 357409-18-8 C₄₂⁽¹³⁾CH₃₈O₆ 
• 357409-21-3 (-)-[4-⁽¹³⁾C]catechin 
• 357409-20-2 C₄₂⁽¹³⁾CH₃₈O₆ 
• 272769-88-7 [4-⁽¹³⁾C]-5,7-dibenzyloxy-2-[3,4-bis(benzyloxy)phenyl]-2H-chromene 

Relevant academic research and scientific papers

Total synthesis of isotopically labelled flavonoids. Part 3: 13C-labelled (-)-procyanidin B3 from 1-[13C]-acetic acid

The regioselectively 13C-labelled (-)-procyanidin B3 was prepared in eight steps from 1-[13C]-acetic acid.

Gram-scale production and applications of optically pure 13C-labelled (+)-catechin and (-)-epicatechin

In this paper gram-scale asymmetric total syntheses of pure (+)-4-[13C]catechin (1) and (-)-4-[13C]epicatechin (2) are described. Labelling was introduced through acylation of a phloroglucinol derivative 4 by 1-[13C]acetic acid, after activation by TFAA. Condensation of the resulting C6-C2 acetophenone building block 6 with a C1-C6 benzaldehyde unit 9 provided the C6-C3-C6 flavonoid skeleton, with benzyl ethers as phenol protecting groups. Asymmetry was introduced by an inexpensive and very efficient resolution process, performed at the penultimate step towards naturally occurring flavan-3-ols, by using tartaric acid derivatives. Both enantiomers of 4-[13C]catechin were obtained with a high level of enantiomeric purity, especially (+)-1 of the natural series. The other enantiomer (-)-1 was a valuable precursor of natural (-)-4-[13C]epicatechin by epimerisation at C-2. These two natural flavanols are thus obtained for the first time in large quantities in optically pure form as labelled compounds and will be useful tools for biological studies using NMR or isotopic mass spectrometry in forthcoming experiments.

Total synthesis of isotopically labelled flavonoids, 2: 13C-labelled (±)-catechin from potassium [13C]cyanide

Racemic 4-[13C]catechin 14 has been synthesized in ten steps starting from potassium [13C]cyanide. The intermediate chalcone 9 was formed by acylation of the benzylated phloroglucinol 7 with the caffeic acid synthon 6, using the trif