Licoarylcoumarin

Molecules. 2014 Mar 28;19(4):3883-97.

Structures of two new flavonoids and effects of licorice phenolics on vancomycin-resistant Enterococcus species.[Pubmed: 24686577]

Since our previous study revealed that several licorice phenolics have antibacterial effects on methicillin-resistant Staphylococcus aureus (MRSA), and suppressive effects on the oxacillin resistance of MRSA, we further investigated effectiveness of licorice constituents on vancomycin-resistant Enterococcus (VRE) bacteria, and purified 32 phenolic compounds.
METHODS AND RESULTS:
Two flavonoids among them were characterized structurally, and identified their structures as demethylglycyrol (31) and 5,7-di-O-methylluteone (32), respectively. Examination of antibacterial effects of licorice phenolics showed that 3-arylcoumarins such as Licoarylcoumarin (9) and glycycoumarin (26), and 2-arylcoumarones such as gancaonin I (17), have moderate to potent antibacterial effects on the VRE strains used in this study.

Chem Pharm Bull (Tokyo). 1989 Nov;37(11):3005-9.

Phenolic constituents of licorice. II. Structures of licopyranocoumarin, licoarylcoumarin and glisoflavone, and inhibitory effects of licorice phenolics on xanthine oxidase.[Pubmed: 2632045]

METHODS AND RESULTS:
An anti-HIV (human immunodeficiency virus) phenolic constituent, licopyranocoumarin (4), and two other new phenolics named Licoarylcoumarin (5) and glisoflavone (6) were isolated from Si-pei licorice (a commercial licorice; root and stolon of Glycyrrhiza sp. from the north-western region of China) using droplet countercurrent chromatography and centrifugal partition chromatography, and their structures were assigned based on chemical and spectroscopic data. Kaempferol 3-O-methyl ether (7) and licocoumarone (8) were also isolated from the licorice.
CONCLUSIONS:
The inhibitory effects of ten licorice phenolics on xanthine oxidase were examined. Licochalcone B (1), glycyrrhisoflavone (2), 8 and licochalcone A (19) showed 50% inhibition at the concentration of 1.3-5.6 x 10(-5) M.

Chem Pharm Bull (Tokyo). 1991 Apr;39(4):930-3.

Inhibition of adenosine 3',5'-cyclic monophosphate phosphodiesterase by flavonoids from licorice roots and 4-arylcoumarins.[Pubmed: 1654220]

Isoliquiritigenin, glabridin, Licoarylcoumarin and licoricidin were identified as strong inhibitors of adenosine 3',5'-cyclic monophosphate (cAMP) phosphodiesterase in waste materials which were obtained during the industrial extraction of glycyrrhizin from licorice roots.
METHODS AND RESULTS:
The structure-activity relationships of 12 flavonoids from licorice roots and 34 4-arylcoumarins were studied. In 4-arylcoumarins, 5,7-dihydroxy derivatives were generally highly inhibitory towards cAMP phosphodiesterase.