@article{oai:nagasaki-u.repo.nii.ac.jp:00004700,
 author = {Matsuo, Yosuke and Tadakuma, Fumiya and Shii, Takuya and Saito, Yoshinori and Tanaka, Takashi},
 issue = {17},
 journal = {Tetrahedron},
 month = {Apr},
 note = {In our previous chemical study of the production mechanism of black tea polyphenols, we demonstrated that Japanese pear fruit homogenate oxidizes green tea catechins bearing pyrogallol-type and catechol-type B-rings to produce theaflavins and dehydrotheasinensins. In contrast, unripe fruit homogenate of Citrus unshiu selectively oxidizes pyrogallol-type catechins to yield only dehydrotheasinensins. The difference in the selectivity of the two homogenates is probably related to the lower redox potential of pyrogallol-type catechins. The oxidation of epigallocatechin with C. unshiu homogenate gave two new compounds, including an ethanol adduct of an oolongtheanin precursor and epigallocatechin 4′-O-rutinoside, together with theasinensin C, dehydrotheasinensin E, and desgalloyl oolongtheanin. The structure of desgalloyl oolongtheanin should be revised based on the spectroscopic and computational data collected in the current study, and a mechanism responsible for the production of oolongtheanins is also proposed., Tetrahedron, 71(17), pp.2540-2548; 2015},
 pages = {2540--2548},
 title = {Selective oxidation of pyrogallol-type catechins with unripe fruit homogenate of Citrus unshiu and structural revision of oolongtheanins},
 volume = {71},
 year = {2015}
}