Synthesis and Evaluation of Antirhinovirus Activity of 3-Hydroxy and 3-Methoxy 2-Styrylchromones

Abstract

Recently, we identified 2-styrylchromones as a new class of antirhinovirus flavonoids with moderate activity against both rhinovirus groups A and B. In order to improve the antiviral effect of the first series of tested 2-styrylchromones, a hydroxy or methoxy group was introduced in position 3 of the chromone ring. Cytotoxicity and antiviral activity of the new synthesized compounds were evaluated in HeLa cell cultures infected with rhinoviruses 1B and 14, selected as representative serotypes for viral groups B and A of human rhinoviruses (HRVs), respectively. These antiviral results compared to those obtained for 3-unsubstituted 2-styrylchromones indicate the greater potency of 3-hydroxy and 3-methoxy derivatives against both serotypes.

Synthesis and Biological Evaluation of 3-Styrylchromone Derivatives as Free Radical Scavengers and α-Glucosidase Inhibitors

“…Having 2a, 2b and 2c in hand, the final step was condensation with phenylacetic acid derivatives (3a-g) in the presence of tert-BuOK in dry pyridine to provide the 3-styrylchromone derivatives (4-13) and allyl-protected products of 3-styrylchromones (14-20), respectively. 3-Styrylchromones having the allyloxy group were submitted to a deprotection step, using Pd(PPh 3 ) 4 in the presence of morpholine in degassed anhydrated THF, for removing the allyl group and affording 3-styrylchromones bearing the hydroxyl group (14)(15)(16)(17)(18)(19)(20).…”

“…Having 2a, 2b and 2c in hand, the final step was condensation with phenylacetic acid derivatives (3a-g) in the presence of tert-BuOK in dry pyridine to provide the 3-styrylchromone derivatives (4-13) and allyl-protected products of 3-styrylchromones (14-20), respectively. 3-Styrylchromones having the allyloxy group were submitted to a deprotection step, using Pd(PPh 3 ) 4 in the presence of morpholine in degassed anhydrated THF, for removing the allyl group and affording 3-styrylchromones bearing the hydroxyl group (14)(15)(16)(17)(18)(19)(20).Biological Activity All synthesized compounds were evaluated for their 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and α-glucosidase inhibitory activities.As shown in Table 1, modifications of 3-styrylchromones on the chromone ring (A-ring) and the phenyl group (B-ring) of the styryl moiety revealed some interesting structure-activity relationships. As a result, the introduction of the methoxy group or halogen atom (F or Cl) substituent (4-13) on the Bring did not show DPPH radical scavenging activity, while the introduction of the hydroxyl group did.…”

Synthesis and Transformation of Halochromones

“…Similar reaction conditions have been successfully used for the synthesis of other mono-and poly-halochromones [85][86][87][88][89]. 6-Fluoroflavone 36 can also be obtained through oxidative cyclization of 5'-fluoro-2'-hydroxychalcone 34 (R = phenyl) with selenium dioxide in hot DMSO (Scheme 12) [84].…”

An Overview of 2‐Styrylchromones: Natural Occurrence, Synthesis, Reactivity and Biological Properties

“…A variety of biological properties have been ascribed to 2-SCs, including antiallergic, [112] anti-inflammatory, [113] antioxidant, [114][115][116][117][118] antitumor [10][11][12]36,39,119] and antiviral, [49,58,66] as well as affinity and selectivity for A 3 adenosine receptors, [38] reviewed by Gomes et al in 2010. [120] Here we update the biological assessment of 2-SCs, but also describe some studies not considered in that review.…”

“…of the halogen led to a mixture of C-6 or C-8 monohalogenated 5-hydroxy-2-styrylchromones 30 (Scheme 6). [54] Other methodologies for preparing 3-hydroxy-2-styrylchromones 26 have also been developed, with 2′-hydroxycinnamylideneacetophenones 23 being treated with hydrogen peroxide in alkaline medium [43,49,50,[55][56][57][58] or diethylamine in a 2:1 mixture of DMSO/1,4-dioxane [47] (Scheme 5). In these cases pyranone ring closure occurs through an Algar-Flynn-Oyamada Scheme 5.…”