Ko WC, Kuo SW, Sheu JR, Lin CH, Tzeng SH and Chen CM |
------>authors3_c=None ------>paper_class1=1 ------>Impact_Factor=None ------>paper_class3=2 ------>paper_class2=1 ------>vol=65 ------>confirm_bywho=sheujr ------>insert_bywho=??? ------>Jurnal_Rank=None ------>authors4_c=None ------>comm_author=1 ------>patent_EDate=None ------>authors5_c=None ------>publish_day=None ------>paper_class2Letter=None ------>page2=275 ------>medlineContent= ------>unit=E0106 ------>insert_date=19991209 ------>iam=1 ------>update_date= ------>author=??? ------>change_event=5 ------>ISSN=None ------>authors_c=None ------>score=500 ------>journal_name=Planta Medica ------>paper_name=Relaxant effects of quercetin methyl ether derivatives in isolated guinea pig trachea and their structure-activity relationships. ------>confirm_date=20010330 ------>tch_id=054002 ------>pmid=10232080 ------>page1=273 ------>fullAbstract=In the present study, we attempted to compare quercetin methyl ethers and to look for the structure-activity relationships, which may be helpful for synthesizing more active compounds for the treatment of asthma. Four present and two previously studied quercetin methyl ethers concentration-dependently relaxed histamine (30 microM), carbachol (0.2 microM) and KCl (30 mM) induced precontraction. According to their IC25 values to histamine-induced precontraction, the potency order was quercetin 3,3~,4,~5,7-pentamethyl ether (QPME), quercetin 3-methyl ether > quercetin, quercetin 3,4~,7-trimethyl ether (ayanin) > quercetin 4~-methyl ether (tamarixetin), quercetin 3,3~,4~,7,-tetramethyl ether (QTME). Therefore, the methylation at 3, at 5, and at both 3 and 7 positions of the A or/and C ring of quercetin nucleus may increase their tracheal relaxant activity. However, the methylation at the 3~ and at the 4~ position of the B ring of quercetin nucleus may decrease their tracheal relaxant activity. ------>tmu_sno=None ------>sno=288 ------>authors2=None ------>authors3=None ------>authors4=None ------>authors5=None ------>authors6=None ------>authors6_c=None ------>authors=Ko WC, Kuo SW, Sheu JR, Lin CH, Tzeng SH and Chen CM ------>delete_flag=0 ------>SCI_JNo=None ------>authors2_c=None ------>publish_area=None ------>updateTitle=Relaxant effects of quercetin methyl ether derivatives in isolated guinea pig trachea and their structure-activity relationships. ------>language= ------>check_flag=0 ------>submit_date= ------>country=None ------>no= ------>patent_SDate=None ------>update_bywho= ------>publish_year=1999 ------>submit_flag= ------>publish_month=None |