title: Synthesis and Antiviral Activity of Quercetin Brominated Derivatives.
abstract: Reaction of quercetin (QR) (1) with bromine under various conditions was studied. Interaction of QR with 2-3 equiv. of bromine in glacial acetic acid at 35-40°C for 2-4 h and 20-22°C for 24 h led to the formation of QR 6,8-dibromide (2) (52-54% yields, 96-98% purity by HPLC). Interaction of QR with 2-5 equiv. bromine in absolute ethanol at 0-5°C and 20-22°C for 24 h led to the formation of 3-O-ethyl-QR-2,3,6,8,5'-pentabromide (3) (95-97% purity by HPLC) the output of which depends on the quantity of bromine. It was shown in MDCK cell culture that compound 2 exhibits a moderate inhibitory activity against pandemic influenza virus A/H1N1/pdm09 (EC50 6.0 µg/mL, CTD50 97.7 µg/mL, SI 16). Compound 3 was inactive.
authors.forename: Elza
authors.initials: E
authors.lastname: Karimova
authors.forename: Lidia
authors.initials: L
authors.lastname: Baltina
authors.forename: Leonid
authors.initials: L
authors.lastname: Spirikhin
authors.forename: Tagir
authors.initials: T
authors.lastname: Gabbasov
authors.forename: Yana
authors.initials: Y
authors.lastname: Orshanskaya
authors.forename: Vladimir
authors.initials: V
authors.lastname: Zarubaev
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000737:chemistry / Q000494:pharmacology*; D001966:Bromine / Q000737:chemistry*; D004285:Dogs; D053118:Influenza A Virus, H1N1 Subtype / Q000187:drug effects / Q000502:physiology; D061985:Madin Darby Canine Kidney Cells; D015394:Molecular Structure; D011794:Quercetin / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000494:pharmacology*
chemical_list: D000998:Antiviral Agents; D011794:Quercetin; D001966:Bromine