ISOFLAVANS DERIVATIVES AS INHIBITORS OF SOYBEAN LIPOXYGENASE: IN-VITRO AND DOCKING STUDIES
摘要:
The lipoxygenases (LOX) are a family of non-heme iron-containing dioxygenases which catalyze the stereospecific insertion of molecular oxygen lino arachidonic acid, leading to hydroxy derivatives as end products. In this work, we studied the behavior of seven isoflavans on 15-soybean lipoxygenases (15-sLOX), comparing them with the known inhibitors quercetin and 3,4-dihydroxybenzoic acid. Four of the seven investigated isoflavans showed IC50 values smaller than 50 mu M, being more potent than quercetin or 3, 4-dihydroxybenzoic acid. Besides a catecholic pattern, the presence of an aromatic ring B seems to confer additional activity to these compounds, a result which was rationalized by docking studies of these isoflavanss into the enzyme binding site.
Enzymatic Studies of Isoflavonoids as Selective and Potent Inhibitors of Human Leukocyte 5-Lipo-Oxygenase
摘要:
Continuing our search to find more potent and selective 5‐LOX inhibitors, we present now the enzymatic evaluation of seventeen isoflavones (IR) and nine isoflavans (HIR), and their in vitro and in cellulo potency against human leukocyte 5‐LOX. Of the 26 compounds tested, 10 isoflavones and 9 isoflavans possessed micromolar potency, but only three were selective against 5‐LOX (IR‐2, HIR‐303, and HIR‐309), with IC50 values at least 10 times lower than those of 12‐LOX, 15‐LOX‐1, and 15‐LOX‐2. Of these three, IR‐2 (6,7‐dihydroxy‐4‐methoxy‐isoflavone, known as texasin) was the most selective 5‐LOX inhibitor, with over 80‐fold potency difference compared with other isozymes; Steered Molecular Dynamics (SMD) studies supported these findings. The presence of the catechol group on ring A (6,7‐dihydroxy versus 7,8‐dihydroxy) correlated with their biological activity, but the reduction of ring C, converting the isoflavones to isoflavans, and the substituent positions on ring B did not affect their potency against 5‐LOX. Two of the most potent/selective inhibitors (HIR‐303 and HIR‐309) were reductive inhibitors and were potent against 5‐LOX in human whole blood, indicating that isoflavans can be potent and selective inhibitors against human leukocyte 5‐LOX in vitro and in cellulo.
Synthesis of Various Kinds of Isoflavones, Isoflavanes, and Biphenyl-Ketones and Their 1,1-Diphenyl-2-picrylhydrazyl Radical-Scavenging Activities
作者:Hideyuki Goto、Yoshiyasu Terao、Shuji Akai
DOI:10.1248/cpb.57.346
日期:——
Forty-eight kinds of isoflavones (8), thirty-one isoflavanes (9), and forty-seven biphenyl-ketones (10, 10′) were synthesized from eleven kinds of substituted phenols (11) and six phenylacetic acids (12). Among them, seventy-five compounds are new. The radical scavenging activities of these compounds were evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) at pH 6.0. We found that thirty-nine out of forty-three compounds having a catechol moiety on either the A- or the B-ring exhibited a high activity (ED50=12—54 μM) similar to that of catechin. In these cases, the remaining part of their structure seemed to have little effect on their activity. Many 6- or 8-hydroxyisoflavanes (9E—I) and their biphenyl-ketone derivatives (10E—H) also showed a high activity (ED50=<50 μM), while all of their corresponding isoflavones (8E—I) were not active at all. The 7-hydroxyisoflavanes having either an additional hydroxyl group at the C5-position (9D) or a methoxy group at the C6-position (9J) presented a high activity (ED50=26—32 μM). This study suggests that natural isoflavones have the possibilities of exhibiting antioxidant activities through the hydroxylation at the C6-, C8-, or C3′-position or the formation of the isoflavanes (9) and/or the biphenyl-ketone derivatives (10′) by metabolism or biotransformation.
Ballio; Pocchiari, Gazzetta Chimica Italiana, 1949, vol. 79, p. 913,918
作者:Ballio、Pocchiari
DOI:——
日期:——
Synthesis of 7-O-?-D-glucopyranosides of isoflavones and their heterocyclic analogues
作者:V. G. Pivovarenko、V. P. Khilya
DOI:10.1007/bf00630111
日期:——
CHROMAN AND CHROMANON-4 DERIVATIVES, PROCESS FOR THEIR PREPARATION, ANTIOXIDANT COMPOSITIONS CONTAINING SAME AND THEIR USE FOR STABILIZING EDIBLE FATS AND OILS
申请人:Z-L LIMITED PARTNERSHIP
公开号:EP0027796B1
公开(公告)日:1984-07-11
ISOFLAVONES AND RELATED COMPOUNDS, METHODS OF PREPARING AND USING AND ANTIOXIDANT COMPOSITIONS CONTAINING SAME