Total synthesis of three naturally occurring 6,8-di-C-glycosylflavonoids: phloretin, naringenin, and apigenin bis-C-beta-D-glucosides.
Three naturally occurring di-C-glycosylflavonoids, phloretin (dihydrochalcone), naringenin (flavanone), and apigenin (flavone) bis-6,8-C-beta-D-glucopyranosides (4, 5, and 6), were synthesized in total yields of 52.3%, 53.5%, and 36.4%, respectively, starting from the key compound, di-C-beta-D-glucopyranosylphloroacetophenone (1). Benzyl protection of the phenolic hydroxyls in 1 and a subsequent aldol condensation with benzyloxybenzaldehyde led to the production of chalcone 3, which, after hydrogenolysis or acid hydrolysis and deprotection, gave 4 and 5, respectively. The acetylation of 5, followed by DDQ oxidation and deprotection, gave 6.
Department of Chemistry and Chemical Engineering, Faculty of Engineering, Yamagata University, 4-3-16 Jonan, Yonezawa-shi, Yamagata 992-8510, Japan. shingo-s@yz.yamagata-u.ac.jp
Shingo
S
Sato
Toshiki
T
Akiya
Hiroaki
H
Nishizawa
Toshiyuki
T
Suzuki
D044950:Flavanones / Q000138:chemical synthesis* / Q000737:chemistry; D047309:Flavones; D005419:Flavonoids / Q000138:chemical synthesis* / Q000737:chemistry; D005960:Glucosides / Q000138:chemical synthesis* / Q000737:chemistry; D006868:Hydrolysis; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010693:Phloretin / Q000138:chemical synthesis* / Q000737:chemistry
D044950:Flavanones; D047309:Flavones; D005419:Flavonoids; D005960:Glucosides; C005273:naringenin; C043562:flavone; D010693:Phloretin