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Introduction Flavonoids are converted to inactive metabolites like glucuronides in the gut, and circulate mainly as glucuronides in blood stream, resulting in low concentrations of active aglycones in plasma. It is therefore unclear how oral flavonoids exert their effects in tissues. We recently reported the plasma pharmacokinetics of some flavonoids and suggested the possibility that the absorbed flavonoids modified macrophage functions leading to enhance bacterial clearance. We aimed to confirm their pharmacological profiles focusing on tissue macrophages. Methods Pseudoinfection was induced by intradermal injection of FITC-conjugated and killed Staphylococcus aureus into the ears of mice treated with or without genistein 7- O-glucuronide (GEN7G, 1 mg/kg, i.v.). FACS analysis was performed on single cell suspensions dispersed enzymatically from the skin lesions at 6 h post pseudoinfection to evaluate phagocytic activities of monocytes/macrophages (CD11b+Ly6G−) and neutrophils (CD11b+Ly6G+). Phagocytosis of the FITC-conjugated bacteria by four glucuronides including GEN7G was evaluated in cultures of mouse macrophages. Results After GEN7G injection, genistein was identified in the inflamed ears as well as GEN7G, and the phagocytic activity of CD11b+Ly6G− cells was increased. GEN7G was converted to genistein by incubation with macrophage-related β-glucuronidase. Macrophage culture assays revealed that GEN7G increased phagocytosis, and the action was dampened by a β-glucuronidase inhibitor. Binding of aglycones to estrogen receptors (ERs), putative receptors of flavonoid aglycones, correlated to biological activities, and glucuronidation reduced the binding to ERs. An ER antagonist suppressed the increase of macrophage function by GEN7G, whereas estradiol enhanced phagocytosis as well. Conclusions This study suggests a molecular mechanism by which oral flavonoids are carried as glucuronides and activated to aglycones by β-glucuronidase in tissue macrophages, and contributes to the pharmacological study of glucuronides. [ABSTRACT FROM AUTHOR]

In the structure of the title compound, {[Rh2(C2H3O2)4(C7H18N2O)]·0.5C4H8O} n or {[Rh2(O2CMe)4(Hbdmap)]·0.5C4H8O} n, where Hbdmap is 1,3-bis­(dimethyl­amino)propan-2-ol, each Hbdmap ligand is coordinated to two [Rh2(O2CMe)4] units by two N atoms, resulting in a polymeric chain structure. The observed coordination mode of the Hbdmap mol­ecule is unprecedented. [ABSTRACT FROM AUTHOR]

In the title compound, 3-[(4-amino-2-methyl-5-pyrimidin-1-io)methyl]-5-(2-hydroxy­ethyl)-4-methyl­thia­zolium(2+) bis(tetra­fluoro­borate), C12H18N4OS2+·2BF4−, the divalent thia­mine cation (in the F conformation) is associated with BF4− anions via two characteristic bridging interactions between the thia­zolium and pyrimidinium rings, i.e. C-H⃛BF4−⃛pyrimidinium and N-H⃛BF4−⃛thia­zolium interactions. Thi­amine mol­ecules are linked by N-H⃛O hydrogen bonds to form a helical chain structure. [ABSTRACT FROM AUTHOR]

In the title compound, 3-[(3,4-di­hydro-2-methyl-4-oxopyrimidin-5-yl)­methyl]-5-(2-hydroxy­ethyl)-4-methyl­thia­zolium hexa­fluoro­phosphate monohydrate, C12H16N3O2S+·PF6−·H2O, oxy­thi­amine is a monovalent cation with a neutral oxo­pyrimidine ring. The mol­ecule assumes the F conformation, which is a common form for thi­amine but which is substantially different from the unusual V conformation found in the chloride and hydro­chloride salts of oxy­thi­amine. The anion-bridging interaction, C-H⃛anion⃛pyrimidine, is emphasized as being important for stabilization of the F conformation. [ABSTRACT FROM AUTHOR]

Review: 236 refs. [ABSTRACT FROM AUTHOR]

The structure of poly[3-[(4-amino-2-methylpyrimidin-1-ium-5-yl)meth­yl]-5-(2-hydroxy­ethyl)-4-methyl­thia­zolium octa-μ-bromo/chloro­(4.4/3.6)-tricadmate(II)], {(C12H18N4OS)[Cd3 Br4.41Cl3.59]} n consists of hydrogen-bonded thia­mine mol­ecules and polymeric cadmium bromide/chloride anions in an organic–inorganic hybrid fashion. The one-dimensional anion ribbons are formed by edge-sharing octa­hedra and vertex-sharing tetra­hedra. Thia­mine mol­ecules adopting the S conformation are linked to anions via three types of inter­actions, namely an N(amino)—H⋯anion⋯thia­zolium bridging inter­action, an N(pyrimidine)—H⋯anion hydrogen bond and an O(hydr­oxy)—H⋯anion hydrogen bond. [ABSTRACT FROM AUTHOR]

The title compound, 3-[(4-amino-2-methyl­pyrimidin-5-yl)­meth­yl]-5-(2-hydroxy­eth­yl)-4-methyl­thia­zolium tetra­phenyl­borate monohydrate, C12H17N4OS+·C24H20B−·H2O, is a salt in which the thiamine cations are linked by hydrogen bonds into a two-dimensional network having (4,4)-topology. The stacked sheets form channels, which are occupied by the anions; the cations and anions are linked by C—H⋯π(arene) hydrogen bonds. [ABSTRACT FROM AUTHOR]

In the title complex, [Ag(C26H36N4)2](C24H20B), the AgI atom has a distorted tetrahedral coordination. The organic ligand is bidentate, coordinating the AgI atom via two imine N atoms. One of the cycloheptyl groups and the Ag atom are disordered over two sites, with occupancy factors of ca 0.87 and 0.13. In this arrangement, the closest methylene group is more remote and the Ag atom also moves out by 0.405 (5) Å toward an alternative position. [ABSTRACT FROM AUTHOR]

The structure of poly[3-[(4-amino-2-methylpyrimidin-1-ium-5-yl)meth­yl]-5-(2-hydroxy­ethyl)-4-methyl­thia­zolium octa-μ-bromo/chloro­(4.4/3.6)-tricadmate(II)], {(C12H18N4OS)[Cd3 Br4.41Cl3.59]} n consists of hydrogen-bonded thia­mine mol­ecules and polymeric cadmium bromide/chloride anions in an organic–inorganic hybrid fashion. The one-dimensional anion ribbons are formed by edge-sharing octa­hedra and vertex-sharing tetra­hedra. Thia­mine mol­ecules adopting the S conformation are linked to anions via three types of inter­actions, namely an N(amino)—H⋯anion⋯thia­zolium bridging inter­action, an N(pyrimidine)—H⋯anion hydrogen bond and an O(hydr­oxy)—H⋯anion hydrogen bond. [ABSTRACT FROM AUTHOR]

In the structure of the title compound, {[Rh2(C2H3O2)4(C7H18N2O)].0.5C4H8O}n or {[Rh2(O2CMe)4(Hbdmap)].0.5C4H8O}n, where Hbdmap is 1,3-bis(dimethylamino)propan-2-ol, each Hbdmap ligand is coordinated to two [Rh2(O2CMe)4] units by two N atoms, resulting in a polymeric chain structure. The observed coordination mode of the Hbdmap molecule is unprecedented.

The structure of poly[3-[(4-amino-2-methylpyrimidin-1-ium-5-yl)methyl]-5-(2-hydroxyethyl)-4-methylthiazolium octa-mu-bromo/chloro(4.4/3.6)-tricadmate(II)], [(C12H18N4OS)[Cd3 Br4.41Cl3.59]]n consists of hydrogen-bonded thiamine molecules and polymeric cadmium bromide/chloride anions in an organic-inorganic hybrid fashion. The one-dimensional anion ribbons are formed by edge-sharing octahedra and vertex-sharing tetrahedra. Thiamine molecules adopting the S conformation are linked to anions via three types of interactions, namely an N(amino)-H...anion...thiazolium bridging interaction, an N(pyrimidine)-H...anion hydrogen bond and an O(hydroxy)-H...anion hydrogen bond.

The title compound, 3-[(4-amino-2-methylpyrimidin-5-yl)methyl]-5-(2-hydroxyethyl)-4-methylthiazolium tetraphenylborate monohydrate, C12H17N4OS+.C24H20B-.H2O, is a salt in which the thiamine cations are linked by hydrogen bonds into a two-dimensional network having (4,4)-topology. The stacked sheets form channels, which are occupied by the anions; the cations and anions are linked by C-H...pi(arene) hydrogen bonds.