169566-44-3

Upstream product

• 10299-59-9 1‐(2‐(benzyloxy)‐6‐hydroxy‐4‐methoxyphenyl)ethan‐1‐one 
• 89025-46-7 2,3,4,6-tetra-O-benzyl-α-D-glucopyranosyl fluoride 
• 39548-86-2 1‐(2‐(benzyloxy)‐4,6‐dihydroxyphenyl)ethan‐1‐one 
• 74808-09-6 2,3,4,6-tetra-O-benzyl-α-D-glucopyranosyl trichloroacetimidate 

Downstream Products

• 381686-09-5 3,4,6'-tris-benzyloxy-3'-C-(2,3,4,6-tetra-O-benzyl-β-D-glucopyranosyl)-2'-hydroxy-4'-methoxychalcone 
• 1437307-71-5 5-benzoyl-4'-benzyloxy-6-C-(2'',3'',4'',6''-tetra-O-benzyl-β-D-glucopyranosyl)-7-methoxyflavone 
• 1437307-72-6 5-benzoyl-6-C-(2'',3'',4'',6''-tetra-O-benzyl-β-D-glucopyranosyl)-4'-hydroxy-7-methoxyflavone 
• 1437307-76-0 5-benzoyl-6-C-(2'',3'',4'',6''-tetra-O-acetyl-β-D-glucopyranosyl)-4'-O-(2''',3''',4''',6'''-tetra-O-acetyl-β-D-glucopyranosyl)-7-methoxyflavone 
• 1437307-74-8 4'-acetoxy-5-benzoyl-6-C-(2'',3'',4'',6''-tetra-O-acetyl-β-D-glucopyranosyl)-7-methoxyflavone 
• 1437307-75-9 5-benzoyl-4'-hydroxy-6-C-(2'',3'',4'',6''-tetra-O-acetyl-β-D-glucopyranosyl)-7-methoxyflavone 
• 16049-42-6 Flavocommelin 
• 381686-10-8 2-(3,4-bis-benzyloxyphenyl)-8-C-(2,3,4,6-tetra-O-benzyl-β-D-glucopyranosyl)-5-hydroxy-7-methoxy-4H-1-benzopyran-4-one 
• 381686-11-9 2-(3,4-bis-benzyloxyphenyl)-8-C-(2,3,4,6-tetra-O-benzyl-β-D-glucopyranosyl)-5,7-dimethoxy-4H-1-benzopyran-4-one 
• 6980-41-2 8-C-β-D-glucopyranosyl-2-(3,4-dihydroxyphenyl)-5-hydroxy-7-methoxy-4H-1-benzopyran-4-one 

Relevant academic research and scientific papers

Concise synthesis of flavocommelin, 7-O-methylapigenin 6-C-, 4′-O-bis-β-d-glucoside, a component of the blue supramolecular pigment from Commelina communis

Flavocommelin, 7-O-methylapigenin 6-C-, 4′-O-bis-β-d-glucoside, was synthesized in 9 steps from the C-glycosylation of 6-O-benzy-4-O- methylphloroacetophenone via the introduction of a cinnamoyl residue by aldol condensation and the formation of a C-ring by regioselective and oxidative ring-closure to regio- and stereoselective O-glycosylation for an overall yield of 31%.

Synthesis of 8-C-glucosylflavones

The syntheses of orientin, parkinsonin A, isoswertiajaponin, and parkinsonin B, which are 8-C-β-D-glucopyranosyl-3′,4′,5,7-tetrahydroxyflavone, 5-methyl orientin, 7-methyl orientin, and 5,7-dimethyl orientin, respectively, are reported herein. The C-glucosyl phloroacetophenone derivatives were obtained via a regio- and stereoselective O → C glycosyl rearrangement. Aldol condensation of the C-glucosyl phloroacetophenone derivatives with 3,4-bisbenzyloxybenzaldehyde afforded the corresponding C-glucosylchalcones. Construction of the flavone system by reaction with I2-Me2SO, followed by the elimination of the 5-benzyl protecting group in the flavone structure, yielded an orientin derivative and a isoswertiajaponin derivative. Methylation of the orientin derivatives with dimethyl sulfate afforded the parkinsonin A derivative, the isoswertiajaponin derivative, and the parkinsonin B derivative. Finally, hydrogenolysis of these C-glucosylflavone derivatives led to the four 8-C-glucosylflavones. The NMR spectra of these C-glucosylflavones showed a duplication of signals corresponding to a major rotamer, along with a minor one. Based on NOESY experiments in Me2SO at ambient temperature, they adopted conformations in which the H-2″ and H-4″ protons in the glucose moiety were oriented toward the B-ring in the flavone structure.

Practical synthesis of a C-glycosyl flavonoid via O→C glycoside rearrangement

The C-glycosylation of 2,3,4,6-tetra-O-benzyl-α-D-glucopyranosyl fluoride and 2-acetylphloroglucinol 3,5-bis(alkyl ether) in the presence of boron trifluoride etherate as an activator stereoselectively gave the β-C-glucoside in a good yield via O→C glycos