Synthesis and biological activity of the tea catechin metabolites, M4 and M6 and their methoxy-derivatives
摘要:
Syntheses are reported for metabolites M4 (1) and M6 (2) of the green tea polyphenols epicatechin (EC) and epigallocatechin (EGC) and their gallate derivatives. Several methoxy-derivatives of 1 and 2 were also prepared. Compounds 1 and 2 were evaluated for growth inhibitory activity against a panel of immortalized and malignant human cell lines with 1 being the more active compound. The possible antiinflammatory activity of 1 and its trimethoxy derivative was also evaluated. Neither compound inhibited the release of arachidonic acid, although 1 inhibited NO production by 50% at 20 muM. (C) 2005 Elsevier Ltd. All rights reserved.
Synthesis and biological activity of the tea catechin metabolites, M4 and M6 and their methoxy-derivatives
摘要:
Syntheses are reported for metabolites M4 (1) and M6 (2) of the green tea polyphenols epicatechin (EC) and epigallocatechin (EGC) and their gallate derivatives. Several methoxy-derivatives of 1 and 2 were also prepared. Compounds 1 and 2 were evaluated for growth inhibitory activity against a panel of immortalized and malignant human cell lines with 1 being the more active compound. The possible antiinflammatory activity of 1 and its trimethoxy derivative was also evaluated. Neither compound inhibited the release of arachidonic acid, although 1 inhibited NO production by 50% at 20 muM. (C) 2005 Elsevier Ltd. All rights reserved.
as ligands for PdII-promoted organic reactions are reported for the first time. These ligands were utilized as catalytic sites and integrated into the skeleton of conjugated microporous polymers. By employing these CMP materials as selective regulators, oxidative Heck reactions between arylboronic esters and electronically unbiased alkenes provide highlyselective linear products.
A General and Highly Selective Chelate-Controlled Intermolecular Oxidative Heck Reaction
作者:Jared H. Delcamp、Alexandria P. Brucks、M. Christina White
DOI:10.1021/ja804120r
日期:2008.8.27
chelate-controlled intermolecular oxidativeHeck reaction is reported that proceeds with a wide range of nonresonance stabilized alpha-olefin substrates and organoboron reagents to afford internal olefin products in good yields and outstanding regio- and E: Z stereoselectivities. Pd-H isomerization, common in many Heck reactions, is not observed under these mild, oxidative conditions. This is evidenced