TY - JOUR
T1 - New flavanol dimers from the bark of celtis tetrandra and their TRAIL Resistance-Overcoming activity
AU - Seephonkai, Prapairat
AU - Ishikawa, Ryusho
AU - Arai, Midori A.
AU - Kowithayakorn, Thaworn
AU - Koyano, Takashi
AU - Ishibashi, Masami
N1 - Funding Information:
P. Seephonkai is gratefully acknowledge to the “Matsumae International Foundation” (MIF), Japan, for financial support during the postdoc fellowship in 2016 to work at Chiba University. P.S. is grateful the Graduate School of Pharmaceutical Science, Chiba University, and Center of Excellence for Innovation in Chemistry (PERC-CIC), Faculty of Science, Mahasarakam University (MSU). Mana Sampai from Graduate School of Pharmaceutical Science, Chiba University, is acknowledged for her generosity of running HRESIMS and MS spectrum.
PY - 2018/4
Y1 - 2018/4
N2 - In the courses of our search for bioactive natural products on TRAIL resistance-overcoming activity, the active EtOAc extract from the bark of Celtis tetrandra was chemically investigated. The fractionation of the extract resulted in the isolation of flavanols; (+)-afzelechin (1), (-)-epiafzelechin (2), (-)-catechin (3), and two new flavanol dimers; (-)-epiafzelechin-(4α8)-(-)-catechin (4) and (-)-epiafzelechin-(4α 8)-(-)-epicatechin (5). All isolated compounds 1-5 were tested for their TRAIL resistance-overcoming activity against AGS cells at the concentrations from 5-20 µM. It is likely that the flavanol dimers 4 and 5 exhibited weak activity in the range of the concentration of 10-20 µM as compared with the standard.
AB - In the courses of our search for bioactive natural products on TRAIL resistance-overcoming activity, the active EtOAc extract from the bark of Celtis tetrandra was chemically investigated. The fractionation of the extract resulted in the isolation of flavanols; (+)-afzelechin (1), (-)-epiafzelechin (2), (-)-catechin (3), and two new flavanol dimers; (-)-epiafzelechin-(4α8)-(-)-catechin (4) and (-)-epiafzelechin-(4α 8)-(-)-epicatechin (5). All isolated compounds 1-5 were tested for their TRAIL resistance-overcoming activity against AGS cells at the concentrations from 5-20 µM. It is likely that the flavanol dimers 4 and 5 exhibited weak activity in the range of the concentration of 10-20 µM as compared with the standard.
KW - (-)-Catechin
KW - Celtis tetrandra
KW - Flavanol dimers
KW - Flavanols
KW - TRAIL resistance-overcoming activity.
UR - http://www.scopus.com/inward/record.url?scp=85048116205&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85048116205&partnerID=8YFLogxK
U2 - 10.1177/1934578x1801300412
DO - 10.1177/1934578x1801300412
M3 - Article
AN - SCOPUS:85048116205
SN - 1934-578X
VL - 13
SP - 427
EP - 430
JO - Natural product communications
JF - Natural product communications
IS - 4
ER -