Two new potent inhibitors of xanthine oxidase from leaves of Perilla frutescens Britton var. acuta Kudo.
A known and a new caffeic ester (1 and 2), new inhibitors of xanthine oxidase (XO), were isolated from leaves of Perilla frutescens var. acuta and their structures have been established as (Z,E)-2-(3,4-dihydroxyphenyl)ethenyl ester (1) and (Z,E)-2-(3,5-dihydroxyphenyl)ethenyl ester (2) of 3-(3,4-dihydroxyphenyl)-2-propenoic acid, respectively, based on detailed spectral studies, including 2D COSY, long range COSY, difference NOE, etc. Both caffeic esters strongly inhibited XO in vitro and especially, the inhibition by 1 was as potent as that by allopurinol. The inhibition mode of 1 was also shown to be non-competitive.
Nakanishi
T
T
Faculty of Pharmaceutical Sciences, Setsunan University, Osaka, Japan.
Nishi
M
M
Inada
A
A
Obata
H
H
Tanabe
N
N
Abe
S
S
Wakashiro
M
M
D010946:Plants, Medicinal / Q000032:analysis*; D014969:Xanthine Oxidase / Q000037:antagonists & inhibitors*
D014969:Xanthine Oxidase