Reference

Preparation of flavonoid compounds for use as therapeutic antioxidants

Preparation of flavonoid compounds for use as therapeutic antioxidants. Caldwell, Stuart Thomas; Bennett, Christopher James; Hartley, Richard Charles; Mcphail, Donald Barton; Duthie, Garry Graeme (Rowett Research Institute, UK). PCT Int. Appl. WO 2004007475 A1 22 Jan 2004, 151 pp. DESIGNATED STATES: W: AE, AG, AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, BZ, CA, CH, CN, CO, CR, CU, CZ, DE, DK, DM, DZ, EC, EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID, IL, IN, IS, JP, KE, KG, KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MA, MD, MG, MK, MN, MW, MX, MZ, NO, NZ, OM, PH, PL, PT, RO, RU, SC, SD, SE, SG, SK, SL, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, YU, ZA, ZM, ZW, AM, AZ, BY, KG, KZ, MD, RU, TJ, TM; RW: AT, BE, BF, BJ, CF, CG, CH, CI, CM, CY, DE, DK, ES, FI, FR, GA, GB, GR, IE, IT, LU, MC, ML, MR, NE, NL, PT, SE, SN, TD, TG, TR. (English). (World Intellectual Property Organization). CODEN: PIXXD2. CLASS: ICM: C07D311-30. ICS: C07D311-32; A61K031-35; A61P039-00. APPLICATION: WO 2003-GB3054 14 Jul 2003. PRIORITY: GB 2002-16371 13 Jul 2002. DOCUMENT TYPE: Patent CA Section: 26 (Biomolecules and Their Synthetic Analogs) Section cross-reference(s): 1, 63, 64 Novel flavonoids, such as I [R6, R7, R8 = H, alkyl, alkenyl; R2', R3', R5' = H, OH] having anti-oxidant activity in biol. systems, were prepd. for pharmaceutical, cosmetic, and food additive uses.Several substances with their cas registry numbers 51-66-1 and 573-11-5 may be metioned in this study. These flavonoids are claimed for use in sunscreen or skincare compns. or to treat conditions involving oxidative damage, esp. curative or prophylactic treatment of Alzheimer's disease, ischemia-reperfusion injury, UV skin damage, skin aging, cancer, heart disease, neurol. disorders, septic shock, diabetes, hepatitis, atherosclerosis, and complications from HIV or hepatitis B infection. Thus, II (R = H) was prepd. via condensation of 4'-ethyl-2'-hydroxyacetophenone with 3,4,5-trimethoxybenzaldehyde using KOH in EtOH to form the corresponding chalcone, 4-Et-2-HO-C6H3COCH:CHC6H2-(OMe)3-3,4,5, in 92% yield, intramol. cyclization of the chalcone using 16% aq. NaOH and 15% aq. H2O2 to give trimethoxyflavone II (R = Me) in 47% yield, and finally, removal of the protecting Me groups using BBr3 in DCM to give the target flavone II (R = H) in 70% yield. The antioxidant potential of the prepd. flavonoids was assessed by their kinetic and stoichiometric redn. of galvinoxyl, a synthetic radical. .