Journal articles: '2'OME'

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Kirschbaum, Kristin, Uta Bönnighausen, Ewald Gesing, Klaus Greiwe, Ulrich Kuhlmann, Henry Strasdeit, Bernt Krebs, and Gerald Henkel. "Eisen- und Cobaltkomplexe mit Schwefelliganden: Darstellung und Kristallstrukturen von [Me4N][FeCl{S2P(OMe)2}2], [Me4N][CoCl{S2P(OMe)2}2], [Et4N][FeCl{S2P(p-C6H4Me)2}2], [Et4N]2[FeCl{ S2PS(OMe) } 2] und [Fe { S2P(OMe)2 }3] / Iron and Cobalt Complexes with Sulfur-Containing Ligands: Preparation and Crystal Structures of [Me4N][FeCl{S2P(OMe)2}2],[Me4N][CoCl{S2P(OMe)2}2], [Et4N][FeCl{S2P(p-C6H4Me)2}2], [Et4N]2[FeCl{S2PS(OMe)}2] and [Fe{S2P(OMe)2}3]." Zeitschrift für Naturforschung B 45, no. 2 (February 1, 1990): 245–57. http://dx.doi.org/10.1515/znb-1990-0219.

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The reaction systems MCl2/K{S2P(OMe)2} (M = Fe(II), Co(II)), FeCl2/Na{S2S2P(p-C6H4Me)2}, and FeCl3/K2{S2PS(OMe)} in methanol afford the mononuclear complexes [FeCl{S2P(OMe)2}2]-, [CoCl{S2P(OMe)2}2]-, [FeCl{S2P(p-C6H4Me)2}2]-, and [FeCl{S2PS(OMe)}2]2-, which were isolated as salts [Me4N][FeCl{S2P(OMe)2}2] (1), [Me4N][CoCl{S2P(OMe)2}2] (2), [Et4N][FeCl{S2P(p-C6H4Me)2}2] (3) and [Et4N]2[FeCl{S2PS(OMe)}2] (4), respectively. Crystals of [Me4N][MCl{S2P(OMe)2}2] are triclinic, space group P 1 (Z = 2): Fe(II), a = 7.165(3), b = 8.628(3), c = 16.526(6)Å, α = 83.98(3), β = 85.32(3), γ = 89.80(3)°; Co(II), a = 7.164(2), b = 8.612(2), c = 16.504(4)Å, α = 84.59(2), β = 84.63(2), γ = 89.41(2)°. The structures of 1 and 2 were refined to R (Rw) = 0.034 (0.043) and 0.028 (0.032), respectively. Compound 3 is monoclinic, space group C2/c, Z = 4 with a = 23.831(5), b = 10.536(3), c = 17.133(4)Å, β = 114.43(3)°. Its structure was refined to R (Rw) = 0.046 (0.052). 4 crystallizes in the orthorhombic space group Pccn with a = 13.310(2), b = 12.982(2), c = 18.968(3) Å, and Z = 4. The refinement converged to R (Rw) = 0.042 (0.039). The anions of the compounds 1—4 contain five-coordinated metal centers which reside in distorted trigonal-bipyramidal (1, 2, and 3) or square pyramidal (4) S4Cl-environments. The neutral complex [Fe{S2P(OMe)2}3] (5) with six-coordinated metal sites was isolated from the reaction system FeCl3/K{S2P(OMe)2} in CH2Cl2. 5 is monoclinic, space group C 2/c (Z = 4) with a = 14.211(2), b = 11.115(2), c = 12.823(2) Å, β = 97.23(1)°. The refinement converged to R (Rw) = 0.022 (0.031). The anions of 1, 2, and 3 represent the first examples of structurally defined mononuclear Fe(II) and Co(II) complexes containing 1,1-dithiolate groups and halide ions simultaneously.

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Bao, Q. B., S. J. Geib, A. L. Rheingold, and T. B. Brill. "Crystal structures and 1JPt-P correlations for trialkyl phosphite-platinum(II) complexes: [Pt[P(OMe)3]4](PF6)2, [Pt[P(OMe)3]3[P(O)(OMe)2]]PF6, cis-Pt[P(OMe)3]2[P(O)(OMe)2]2, [ClPt[P(OMe)3]3]PF6, and cis-Cl2Pt[P(OMe)3]2." Inorganic Chemistry 26, no. 21 (October 1987): 3453–58. http://dx.doi.org/10.1021/ic00268a009.

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Pruchnik, Florian P., Radoslaw Starosta, Zbigniew Ciunik, Adam Opolski, Joanna Wietrzyk, Elzbieta Wojdat, and Danuta Dus. "Tetraacetatodirhodium(II) complexes with tris(methoxyphenyl)phosphines, their reactivity, structure, and antitumor activity." Canadian Journal of Chemistry 79, no. 5-6 (May 1, 2001): 868–77. http://dx.doi.org/10.1139/v01-080.

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Reactions of [Rh2(µ-OAc)4(H2O)2] ([1·(H2O)2]) with tris(3-methoxyphenyl)phosphine at 1:1 and 1:2 molar ratios yield, first, the appropriate adducts: [1·(H2O){P(C6H4-3-OMe)3}] and [1·{P(C6H4-3-OMe)3}2], and then [Rh2(µ-OAc)3{µ-(C6H3-3-OMe)P(C6H4-3-OMe)2}(HOAc)2] ([2·(HOAc)2]), and [Rh2(µ-OAc)2{µ-(C6H3-3-OMe)P(C6H4-3-OMe)2}2(HOAc)2] ([3·(HOAc)2]) complexes, respectively. They have been characterized by spectroscopic methods. The molecular structure of [3·(HOAc)(H2O)] has been determined crystallographically. The complexes [3·(HOAc)2], [Rh2(µ-OAc)3{µ-(C6H3-4-OMe)P(C6H4-4-OMe)2}(HOAc)2] ([4·(HOAc)2]), and [Rh2(µ-OAc)2{µ-(C6H3-4-OMe)P(C6H4-4-OMe)2}2(HOAc)2] ([5·(HOAc)2]) reversibly react with CO giving mono- and biadducts. Antitumor activity of binuclear rhodium(II) compounds [3·(HOAc)2], [Rh2(µ-OAc)3{µ-(C6H3-2-O)P(C6H3-2-OMe)2}(HOAc)] ([6·(HOAc)]), and [Rh2(µ-OAc)3{µ-(C6H3-6-OMe-2-O)P[(C6H3-2,6-(OMe)2]2}(HOAc)] ([7·(HOAc)]) have been investigated in vitro. The most active agent for investigated tumor lines is complex [6·(HOAc)]. It shows higher activity than cisplatin (cis-[PtCl2(NH3)2]). Antitumor activity decreases in the series: [6·(HOAc)] > [7·(HOAc)] > [3·(HOAc)2]. Activity of all investigated rhodium(II) complexes is higher than that of [1·(H2O)2].Key words: dirhodium(II) complexes, functionalized phosphines, aryl phosphines, ferrocenylmethylphosphines, adducts with CO, antitumor activity, orthometallation reactions.

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Thiele, DL, and PE Lipsky. "Spectrum of toxicities of amino acid methyl esters for myeloid cells is determined by distinct metabolic pathways." Blood 79, no. 4 (February 15, 1992): 964–71. http://dx.doi.org/10.1182/blood.v79.4.964.964.

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Abstract L-leucine methyl ester (Leu-OMe), Leu-Leu-OMe, Phe-OMe, and Glu-(OMe)2 are toxic to mononuclear phagocytes (M phi) and neutrophils. In the present studies, the mechanism of this toxicity was examined. A concentration of NH4Cl known to neutralize lysosomal pH and to block conversion of Leu-OMe to the dipeptide condensation product Leu-Leu-OMe inhibited Leu-OMe- or Glu-(OMe)2- but not Leu-Leu-OMe-mediated M phi toxicity. Leu-OMe-, Glu-(OMe)2-, or Leu-Leu-OMe-mediated killing of M phi was prevented by Gly-Phe-CHN2, a specific inhibitor of the thiol protease, dipeptidyl peptidase I (DPPI). Neither NH4Cl nor Gly-Phe-CHN2 prevented Phe-OMe-mediated M phi toxicity. In contrast, inhibition of M phi serine esterase activity prevented Phe-OMe- but not Leu-OMe- or Glu- (OMe)2-mediated killing of M phi. The myeloid tumor lines U937, HL60, and THP-1 were found to be uniformly enriched in DPPI and susceptible to Leu-Leu-OMe but not Leu-OMe toxicity. Whereas HL60 were resistant to Phe-OMe, THP-1 cells were killed by this agent. Incubation of peripheral blood mononuclear cells with Leu-OMe resulted in loss of natural killer (NK) functions and cytotoxic T lymphocytes (CTL) precursors, a process that requires the DPPI-dependent generation of membranolytic polymerization products. Phe-OMe had no toxic effects on NK cells or CTL precursors. These results indicate that Leu-OMe and Glu- (OMe)2 toxicity for M phi is related to the production of higher molecular weight hydrophobic polymerization products via the sequential action of two nonserine esterase lysosomal enzymes. In contrast, Phe- OMe toxicity for myeloid cells was found to correlate with serine esterase-mediated intracellular trapping of high concentrations of the free amino acid Phe. These distinct enzymatic mechanisms may provide a unique means of targeting agents capable of selectively deleting cells of myeloid lineage.

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Thiele, DL, and PE Lipsky. "Spectrum of toxicities of amino acid methyl esters for myeloid cells is determined by distinct metabolic pathways." Blood 79, no. 4 (February 15, 1992): 964–71. http://dx.doi.org/10.1182/blood.v79.4.964.bloodjournal794964.

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L-leucine methyl ester (Leu-OMe), Leu-Leu-OMe, Phe-OMe, and Glu-(OMe)2 are toxic to mononuclear phagocytes (M phi) and neutrophils. In the present studies, the mechanism of this toxicity was examined. A concentration of NH4Cl known to neutralize lysosomal pH and to block conversion of Leu-OMe to the dipeptide condensation product Leu-Leu-OMe inhibited Leu-OMe- or Glu-(OMe)2- but not Leu-Leu-OMe-mediated M phi toxicity. Leu-OMe-, Glu-(OMe)2-, or Leu-Leu-OMe-mediated killing of M phi was prevented by Gly-Phe-CHN2, a specific inhibitor of the thiol protease, dipeptidyl peptidase I (DPPI). Neither NH4Cl nor Gly-Phe-CHN2 prevented Phe-OMe-mediated M phi toxicity. In contrast, inhibition of M phi serine esterase activity prevented Phe-OMe- but not Leu-OMe- or Glu- (OMe)2-mediated killing of M phi. The myeloid tumor lines U937, HL60, and THP-1 were found to be uniformly enriched in DPPI and susceptible to Leu-Leu-OMe but not Leu-OMe toxicity. Whereas HL60 were resistant to Phe-OMe, THP-1 cells were killed by this agent. Incubation of peripheral blood mononuclear cells with Leu-OMe resulted in loss of natural killer (NK) functions and cytotoxic T lymphocytes (CTL) precursors, a process that requires the DPPI-dependent generation of membranolytic polymerization products. Phe-OMe had no toxic effects on NK cells or CTL precursors. These results indicate that Leu-OMe and Glu- (OMe)2 toxicity for M phi is related to the production of higher molecular weight hydrophobic polymerization products via the sequential action of two nonserine esterase lysosomal enzymes. In contrast, Phe- OMe toxicity for myeloid cells was found to correlate with serine esterase-mediated intracellular trapping of high concentrations of the free amino acid Phe. These distinct enzymatic mechanisms may provide a unique means of targeting agents capable of selectively deleting cells of myeloid lineage.

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Jeong, Ju-Mi, Cheol-Hee Choi, Su-Kyeong Kang, In-Hwa Lee, Ji-Yoon Lee, and Hyuk Jung. "Antioxidant and Chemosensitizing Effects of Flavonoids with Hydroxy and/or Methoxy Groups and Structure-Activity Relationship." Journal of Pharmacy & Pharmaceutical Sciences 10, no. 4 (October 26, 2007): 537. http://dx.doi.org/10.18433/j3kw2z.

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Purpose. Flavonoids have been used as antioxidant, chemopreventive and chemosensitizing agents. In this study, eleven flavonoids containing a variety of hydroxy (OH) and/or methoxy (OMe) groups were evaluated for their antioxidant, cytotoxic and chemosensitizing effects to create a structure-activity relationship (SAR). Methods. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical solution-based chemical assay and and 2',7'-dichlorofluorescin diacetate (DCFH-DA) cellular-based assay were used to compare the free radical scavenging activity on the same molar concentration basis using the AML-2/DX100 cells which are characterized by the down-regulated expression of catalase and resulting supersensitiviy to hydrogen peroxide. The chemosensitization and cytotoxicity were determined by the MTT assay in the presence or absence of an anticancer drug using the P-glycoprotein-overexpressing AML-2 subline AML-2/D100 cells. Results. The antioxidant activity of the flavonoid (3,5,7,3’,4’-OH) was higher than that of the flavonoid (5,7,3’,4’-OH). Flavonoids substituted with the various number of OMe decreased antioxidant activity. Flavonoids with 7-OH or 5,7-OH groups have the highest cytotoxicity, and flavonoids with 5,7-OMe group intermediate cytotoxicity. The IC50 values of flavonoid (5,7-OMe, 3’,4’,5’-OMe) and flavonoid (5,7-OMe, 4’-OMe), 0.4 M and 1.4 M. The IC50 values of flavonoid (5,6,7-OMe, 3’,4’-OMe) and flavonoid (5,6,7-OMe, 3’,4’,5’-OMe), 3.2 uM and 0.9 M, respectively, and those of flavonoid (5,6,7-OMe, 3’,4’,5’-OMe) and flavonoid (5,7-OMe,3’,4’,5’-OMe) were 0.9 M and 0.4 M, respectively. Conclusions. These results suggest that flavonoids with 3-OH group play a positive role in antioxidant activities, flavonoids with 5-OH and/or 7-OH groups show the higher cytotoxicity, and flavonoids with 3’-OMe and/or 5’-OMe groups plays positive but 6-OMe groups negative roles in the P-glycoprotein (Pgp) inhibition. It is believed that these SAR results can be taken into account for the development of flavonoids with high therapeutic index.

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Silva Filho, Clelio Mendes da, Carolina Rocha Souza, Estela dos Santos Christo, Laura Pires Ligeiro, Raphael Costa Silva, Sarah Michalsky Martins, Felipe Alves de Oliveira, Noelle Satiro de Araújo, Riquelme Romero Leal Portela, and Ana Silvia Menezes Bastos. "O manejo clínico da otite média aguda em crianças: uma revisão bibliográfica." Revista Eletrônica Acervo Saúde 15, no. 8 (August 17, 2022): e10752. http://dx.doi.org/10.25248/reas.e10752.2022.

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Objetivo: Analisar através de uma revisão narrativa sobre as condutas clínicas da Otite Média Aguda (OMA) nas crianças. Revisão bibliográfica: A infância é caracterizada por Otite Média (OM), que é definida por infecção da orelha média que acomete principalmente a fase pré-escolar. Essa patologia se sub categoriza em: OMA, Otite Média aguda recorrente, Otite Média com efusão e Otite Média Crônica (OMC). A sintomatologia da OMA é marcada por febre, irritabilidade, otorreia, anorexia e vômitos. Anatomicamente, a criança apresenta a tuba auditiva mais horizontalizado que nos adultos, o que corrobora para o desenvolvimento da OMA. A doença costuma ser precedida por infecção viral do trato respiratório superior e provoca edema da tuba auditiva. A complicação mais comum da OMA é a mastoidite aguda que favorece o acúmulo de secreção purulenta e a colonização bacteriana, que obtém melhora com antibiótico. Considerações finais: A otite média é uma doença que atinge crianças de 2-6 anos juntamente com a sintomatologia característica. O diagnóstico se assemelha entre OME e OMC que dificulta um desfecho. A resolução pode ser espontânea em sua maioria com uso de sintomáticos. O antibiótico é reservado para a prevenção de possíveis complicações.

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Mehmood, Andleeb, Xiaowei Xu, Xiaohui Kang, and Yi Luo. "Origin of different chain-end microstructures in ethylene/vinyl halide copolymerization catalysed by phosphine–sulfonate palladium complexes." New Journal of Chemistry 44, no. 39 (2020): 16941–47. http://dx.doi.org/10.1039/d0nj03350b.

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Ethylene and vinyl halide (VX, X = F or Cl) copolymerization mechanism in the presence of catalysts A ((PO^OMe,OMe)PdMe, PO^OMe,OMe = {2(2-MeOC₆H₄)(2-SO₃-5-MeC₆H₃)P}) and A′ ((PO^Bp,OMe)PdMe, PO^Bp,OMe = {(2-MeOC₆H₄)(2-{2,6-(MeO)₂C₆H₃}C₆H₄)(2-SO₃-5-MeC₆H₃)P}) has been comparatively studied via density functional theory (DFT) calculations.

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Mattes, Rainer, Heinz Scholand, Ulrich Mikloweit, and Volker Schrenk. "Reaktion von DioxomoIybdän(VI)-Komplexen mit O-Methyl-thiocarbazat Darstellung und Charakterisierung von Schiffbase-, Hydrazido- und Diazenido-Komplexen des Molybdäns / Reaction of Dioxomolybdenum(VI) Complexes with O-Methylthiocarbazate Synthesis and Characterization of Schiffbase, Hydrazido and Diazenido Complexes of Molybdenum." Zeitschrift für Naturforschung B 42, no. 5 (May 1, 1987): 599–604. http://dx.doi.org/10.1515/znb-1987-0513.

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transThe reaction of NH2NHC(S)OR, (R = Me, Et) with MoO2(acac)2 yields the dimeric complexes MO2O3(MeC(O)CHC(Me)NNC(S)0R)2 (1) with the planar O = Mo - O - Mo = O group. The tetradentate O,N,S-donor ligand is formed through condensation of acetylacetone with the organohydrazine. The reactions of NH2NHC(S)OMe with MoO2(S2CNEt2)2 and MoO2(ONEt2)2 give the diazenido hydrazido complexes Mo(NNC(S)OMe)(NH2NC(S)OMe)(S2CNEt2)2·CH2Cl2(2) and Mo(NNC(S)OMe)(NH2NC(S)OMe)2(ONEt2) (4). The metal atoms in both compounds are seven coordinated and contain the approximately linear diazenido ligand NNC(S)OMe and one (2) or two (4) N,S-chelating hydrazido(1-) ligands NH2NC(S)OMe. 2 has crystallographically imposed mirror symmetry. Recrystallization of 2 from toluene in air gives the asymmetric dinuclear complex (Et2NCS2)(O)Mo(μ-NNC(S)OMe)2Mo(S2CNMe2) (3). The Mo-Mo distance is 267.0(2) pm. One Mo site has square pyramidal MoOS2N2 geometry, the other trigonal prismatic MoN2S4 geometry. The coordination of the bridging N atoms is slightly pyramidal. The compounds 1, 2 and 3 have been further characterized by vibrational spectroscopy.

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Chen, Zhao, Chet Jablonski, and John Bridson. "Evidence for an intramolecular transition metal Arbuzov reaction." Canadian Journal of Chemistry 74, no. 11 (November 1, 1996): 2083–94. http://dx.doi.org/10.1139/v96-237.

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Reaction of [CpCo(C3F7)(I)(L)], (L = PPh2Me (1a), PPhMe2 (1b), PMe3 (1c), and PPh(OMe)2 (2)), with PPh(OMe)2 affords diastereomeric Co-and P-chiral metallophosphinates CpCo(C3F7)(L)(P(O)Ph(OMe)), 4a,b,c and 6, respectively. The solid state structure and relative configuration of the lower Rf diastereomeric phosphinate CpCo(C3F7)(PPh(OMe)2)(P(O)Ph(OMe)), 6-2, was determined by X-ray diffraction. RR;SS-6-2 crystallizes in the triclinia system with space group [Formula: see text](no. 2), with a = 12.928(4) Å, b = 14.683(4) Å, c = 7.666(2) Å, a = 103.50(2)°, β = 101.31(3)°, γ = 109.50(2)°, V = 1272.8(7) Å3, Z = 2, and R = 0.036 (Rw = 0.030) for 2867 reflections with I > 3.00σ(I). CpCo(C3F7)(I)(PPh(OMe)2), 2, reacts with PPh2Me to yield the same Co-and P-chiral phosphinate products as obtained for the reaction of 1a with PPh(OMe)2, albeit with different optical yields. The product stereochemistry is not accounted for by the established mechanism for transition metal Arbuzov-like dealkylations, which requires formation of a common, ionic intermediate [CpCo(C3F7)(PPh2Me)(PPh(OMe)2)]+, 3, via iodide substitution and subsequent nucleophilic attack at carbon. A parallel intramolecular dealkylation pathway is proposed to account for the results. Key words: stereochemistry, mechanism, Arbuzov, Co(III) complex, chiral metal. X-ray

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Jaafar, Mariam, Hermes Paraqindes, Mathieu Gabut, Jean-Jacques Diaz, Virginie Marcel, and Sébastien Durand. "2′O-Ribose Methylation of Ribosomal RNAs: Natural Diversity in Living Organisms, Biological Processes, and Diseases." Cells 10, no. 8 (July 31, 2021): 1948. http://dx.doi.org/10.3390/cells10081948.

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Recent findings suggest that ribosomes, the translational machineries, can display a distinct composition depending on physio-pathological contexts. Thanks to outstanding technological breakthroughs, many studies have reported that variations of rRNA modifications, and more particularly the most abundant rRNA chemical modification, the rRNA 2′O-ribose methylation (2′Ome), intrinsically occur in many organisms. In the last 5 years, accumulating reports have illustrated that rRNA 2′Ome varies in human cell lines but also in living organisms (yeast, plant, zebrafish, mouse, human) during development and diseases. These rRNA 2′Ome variations occur either within a single cell line, organ, or patient’s sample (i.e., intra-variability) or between at least two biological conditions (i.e., inter-variability). Thus, the ribosomes can tolerate the absence of 2′Ome at some specific positions. These observations question whether variations in rRNA 2′Ome could provide ribosomes with particular translational regulatory activities and functional specializations. Here, we compile recent studies supporting the heterogeneity of ribosome composition at rRNA 2′Ome level and provide an overview of the natural diversity in rRNA 2′Ome that has been reported up to now throughout the kingdom of life. Moreover, we discuss the little evidence that suggests that variations of rRNA 2′Ome can effectively impact the ribosome activity and contribute to the etiology of some human diseases.

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Adonin, Nicolai Yu, Vadim V. Bardin, and Hermann-Josef Frohn. "Polyfluoroorganoboron-Oxygen Compounds. 7. Studies of Conversion of [(C6HnF5-n)B(OMe)3]- Into [(C6HnF5-n)2B(OMe)2]- (n = 0, 1)." Collection of Czechoslovak Chemical Communications 73, no. 12 (2008): 1681–92. http://dx.doi.org/10.1135/cccc20081681.

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Conversion of salts Li[(C6HnF5-n)B(OMe)3] (n = 0, 1) into (Li·DME)[(C6HnF5-n)2B(OMe)2] was studied in dichloromethane-DME solution. The observed rate constants k decrease from (21.4 ± 0.9) × 10-3 l mol-1 s-1 (Li[C6F5B(OMe)3]) over (6.99 ± 0.11) × 10-3 l mol-1 s-1 (Li[(2,3,5,6-C6HF4)B(OMe)3]) to (2.94 ± 0.05) × 10-3 l mol-1 s-1 (Li[(2,3,4,6-C6HF4)B(OMe)3]), while Li[(2,3,4,5-C6HF4)B(OMe)3] does not undergo any transformation. Hydrolysis of (Li·DME)[(C6HnF5-n)2B(OMe)2] leads to corresponding borinic acids, whereas treatment of them with aqueous solution of M[HF2] (M = Bu4N, K) acidified with HF results in M[(C6HnF5-n)2BF2] in high yields.

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Nachmani, Daphna, Lourdes M. Mendez, and Pier Paolo Pandolfi. "Aberrant rRNA 2'-O-Methylation Causes Bone Marrow Failure and Defective Immune Function." Blood 136, Supplement 1 (November 5, 2020): 11–12. http://dx.doi.org/10.1182/blood-2020-141809.

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RNA modifications are emerging as key determinants of development and disease. Understanding the mechanisms regulating their functional impact is crucial to uncovering their relevance for disease pathology. The NPM1 gene is frequently a target of genetic alteration in hematological tumors, particularly of the myeloid lineage. While extensively studied, the mechanisms by which NPM1 exert its impact on HSPCs are still not fully elucidated. Recently, we have identified NPM1 as an essential regulator of rRNA 2'-O-methylation (2'OMe). We found that NPM1, through its RNA-binding activity, binds C/D box small nucleolar RNAs (snoRNAs) in the nucleolus, to regulate rRNA 2'OMe, and thereby controls translation. Additionally, we identified NPM1 germ-line mutations in dyskeratosis congenita patients presenting with BMF. Characterization of these mutations found them as selectively deficient in snoRNA binding, and thus their expression led to reduce 2'OMe levels and aberrant translation in patient cells. To causally link reduced 2'OMe to dyskeratosis congenita manifestation, we generated mice harboring a dyskeratosis congenita germ-line NPM1 mutation. The KI mice phenocopy both hematological and non-hematological DC features, thus casually linking mutated NPM1 and reduced 2'OMe to bone marrow failure. Currently, we are taking advantage of our Npm1-mutated mouse model to explore the role of 2'OMe in mature immune cell function. We find that aberrant 2'OMe in mature macrophages (due to Npm1 mutation) does not affect their maturation, however, it leads to altered functions. Specifically, we find that Npm1-mutated macrophages, with reduced 2'OMe, display reduced production of reactive oxygen species, chemotactic properties and phagocytic capacity. These studies demonstrate a role for Npm1 and 2'OMe in adult immune cells, and reveal the importance of translation regulation in both hematopoietic stem cells and mature macrophage function. Figure Disclosures No relevant conflicts of interest to declare.

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He, Xiao-Yang, Jing Wang, Dan-Dan Lu, and Sheng-Qi Wang. "Synthesis and Antisense Properties of 2′β-F-Arabinouridine Modified Oligonucleotides with 4′-C-OMe Substituent." Molecules 23, no. 9 (September 17, 2018): 2374. http://dx.doi.org/10.3390/molecules23092374.

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A novel 2′-F,4′-C-OMe–arabinouridine (araU) was successfully synthesized and introduced into oligonucleotides. The oligonucleotide containing 2′-F,4′-C-OMe–araU exhibited improved nuclease resistance and RNA hybridizing selective ability relative to 2′-F–araU. In particular, when 2′-F,4′-C-OMe–araU inserted into C–H⋯F–C bonding-favorable 5′–uridine–purine–3′ steps, the modified oligonucleotide showed remarkable binding affinity and selectivity to RNA complements. Thus, 2′-F,4′-C-OMe–araU has valuable antisense properties and can be used as novel chemical modification for antisense therapeutic strategy.

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Sharma, Simpal, Rajendra K. Sharma, Audhesh K. Rai, and Yashpal Singh. "Synthesis and Characterisation of Phenylantimony(III) Derivatives of 2-(2-hydroxyphenyl) Benzothiazolines." Journal of Chemical Research 2005, no. 7 (July 2005): 457–60. http://dx.doi.org/10.3184/030823405774309122.

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Equimolar reactions of PhSb(OMe)2 (prepared in situ) and 2-(2-hydroxyphenyl)benzothiazolines LH2 yield the addition products PhSb(OMe)2LH2, while equimolar reactions of PhSbCl2 with Na2L yield Schiff's base derivatives PhSbL, with rearrangement of the benzothiazoline ring. All these derivatives have been characterised by elemental analyses and plausible structures established

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Kdider, Mohamed, Catherine Elleouet, François Y. Pétillon, and Philippe Schollhammer. "Mono- and Dinuclear Carbonyl Dithiolene Complexes Related to the [FeFe]-Hydrogenases." Molbank 2023, no. 3 (September 6, 2023): M1719. http://dx.doi.org/10.3390/m1719.

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The di-iron carbonyl dithiolene bridged complex [Fe2(CO)6(µ-S2C2(CO2Me)2)] (1) reacts with 1 equivalent of phosphane PR3 (R = Ph, OMe) to give, as major products, monosubstituted derivatives [Fe2(CO)5L(µ-S2C2(CO2Me)2)] (L = PPh3 (2), P(OMe)3 (3)). In the presence of an excess (3–4 equiv.) of P(OMe)3, the cleavage of 1 arises partly and a mixture of the mononuclear species [Fe(CO)(P(OMe)3)2(κ2-S2C2(CO2Me)2)] (4) and 3 is obtained. The compounds 2–4 were analyzed by IR and 1H, 31P-{1H} NMR spectroscopies. Their structures in solid state were determined by X-ray diffraction analyses, which accord with their spectroscopic characteristics.

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17

Thiele, D. L., M. R. Charley, J. A. Calomeni, and P. E. Lipsky. "Lethal graft-vs-host disease across major histocompatibility barriers: requirement for leucyl-leucine methyl ester sensitive cytotoxic T cells." Journal of Immunology 138, no. 1 (January 1, 1987): 51–57. http://dx.doi.org/10.4049/jimmunol.138.1.51.

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Abstract L-leucyl-L-leucine methyl ester (Leu-Leu-OMe) is selectively toxic for human natural killer (NK) cells and cytotoxic T lymphocytes (CTL) at both the precursor and effector stage of differentiation. The present studies explored the effects of Leu-Leu-OMe on murine spleen cell function. Leu-Leu-OMe exposure removed NK function from murine spleen cells but spared their capacity to proliferate in response to lipopolysaccharide and Con A. The capacity to generate CTL from both L3T4 (+) and Lyt-2 (+) precursors was lost after Leu-Leu-OMe treatment, whereas alloantigen-induced proliferation and interleukin 2 (IL 2) production by L3T4 (+) T helper cells remained intact. Lethal graft vs host disease (GVHD), which developed in irradiated (C57BL/6 X DBA/2)F1 recipients of C57BL/6 bone marrow and spleen cells was completely prevented by Leu-Leu-OMe treatment of donor cells. In contrast depletion of Lyt-2 positive cells from the donor inoculum did not prevent acute GVHD in this fully major histo-compatibility complex (MHC) incompatible strain combination. However, Leu-Leu-OMe treatment of the Lyt-2 depleted inoculum completely prevented lethal GVHD, although the treated cells retained the capacity to proliferate and secrete IL 2 normally after in vitro stimulation with (C57BL/6 X DFA/2)F1 spleen cells. These findings indicate that L3T4 (+) T helper cells alone are unable to initiate lethal GVHD in this H-2 incompatible strain combination. Rather, lethal GVHD requires the transfer of a Leu-Leu-OMe sensitive T cell subset, likely to be thymus educated pre-CTL. Leu-Leu-OMe treatment should provide a useful way to delineate subpopulations of cells involved in the production of lethal GVHD and an approach to preventing this complication of bone marrow transplantation.

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18

D’Andréa, Grégoire, Claude Maschi, Charles Savoldelli, Hervé Caci, and Sonanda Bailleux. "Otologic Outcomes With Two Different Surgical Protocols in Patients With a Cleft Palate." Cleft Palate-Craniofacial Journal 55, no. 9 (February 28, 2018): 1289–95. http://dx.doi.org/10.1177/1055665618758686.

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Objective: To compare otologic outcomes in patients with cleft palate who underwent 2 different surgical protocols. Design: Monocentric retrospective analysis of medical reports. Patients, Participants: All consecutively treated patients affected by a cleft palate, born between January 1998 and December 2002 (group 1) and between January 2007 and December 2010 (group 2). Interventions: Patients in group 1 underwent Veau-Wardill-Kilner palatoplasty at 10 months and had ventilation tubes inserted in case of otitis media with effusion (OME) during surgery. Patients in group 2 underwent Sommerlad intravelar veloplasty at 5 months. Ventilation tubes were inserted only in case of persistent OME. Main Outcome Measure(s): The need for a second set of ventilation tubes to be inserted in case of persistent OME, the presence of OME at the age of 2 years, and tympanic abnormalities at the age of 5 years were analyzed. Results: There was no statistically significant difference either for the presence of OME at the age of 2 years (27 [45%] vs 32 [57.14%], respectively, in groups 1 and 2; P = .191) or for tympanic abnormalities at the age of 5 years (20 [33.33%] vs 15 [26.79%]; P = .433). Statistically significant difference was found for the need to insert a second set of ventilation tubes in case of persistent OME (29 [48.33%] vs 12 [21.42%], respectively; P = .02). Conclusion: Early Sommerlad intravelar veloplasty may reduce persistent OME and consequently the need for ventilation tubes insertion, compared to later Veau-Wardill-Kilner palatoplasty.

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19

Kang, Hyunkyu, Shuncheng Liu, Shahid N. Shaikh, Terrence Nicholson, and Jon Zubieta. "Synthesis and structural investigation of polyoxomolybdate coordination compounds displaying a tetranuclear core. Crystal and molecular structures of [Bu4N]2[Mo4O10(OMe)2(OC6H4O)2] and to the diazenido complexes [Bu4N]2[Mo4O6(OMe)2(HNC6H4O)2(NNC6H5)4] and [Bu4N]2[Mo4O6(OMe)2(C10H6O2)2(NNC6H5)4]. Comparison to a binuclear complex with the [Mo2(OMe)2(NNC6H5)4]2+ core, [Mo2(OMe)2(H2NC6H4O)]." Inorganic Chemistry 28, no. 5 (March 1989): 920–33. http://dx.doi.org/10.1021/ic00304a024.

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20

Shan, Xuan, Zhao Jing, Bingrong Sun, Ping Chang, Lixin Wu, and Xiaohui Ma. "Influence of the Ocean Mesoscale Eddy–Atmosphere Thermal Feedback on the Upper-Ocean Haline Stratification." Journal of Physical Oceanography 50, no. 9 (September 1, 2020): 2475–90. http://dx.doi.org/10.1175/jpo-d-19-0193.1.

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AbstractThe ocean mesoscale eddy–atmosphere (OME-A) interaction through the eddy-induced sea surface temperature anomaly can feedback on ocean dynamics in various ways (referred to as the OME-A thermal feedback). In this study, the influence of the OME-A thermal feedback on the upper-ocean haline structure is analyzed based on high-resolution coupled simulations. In the Oyashio Extension where pronounced surface temperature and salinity fronts are collocated, the haline stratification in the upper 200 m is significantly enhanced by the OME-A thermal feedback. This enhancement is mainly attributed to the weakening of the upward eddy salinity transport in response to the OME-A thermal feedback. The OME-A thermal feedback influences the vertical eddy salinity transport through its differed impacts on the mesoscale buoyancy and temperature anomaly variances. As temperature and salinity in the Oyashio Extension are strongly compensated for their effects on buoyancy, the dissipation of the mesoscale buoyancy anomaly variance b′2 by the OME-A thermal feedback is considerably weaker than that estimated from the mesoscale temperature anomaly alone, i.e., (gαT′)2, with g the gravity acceleration and α the thermal expansion coefficient. Correspondingly, the vertical eddy buoyancy transport (w′b′) is weakened by the OME-A thermal feedback to a lesser extent than its thermal component (gαw′T′). The different responses of w′b′ and gαw′T′ to the OME-A thermal feedback are reconciled by the reduced vertical eddy salinity transport.

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21

Hörnig, A., U. Englert, and U. Koelle. "Reactions of [(η5-C5Me5)Ru(OMe)]2." Journal of Organometallic Chemistry 453, no. 2 (July 1993): 255–61. http://dx.doi.org/10.1016/0022-328x(93)83119-g.

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22

Kölle, U., A. Hörnig, and U. Englert. "Reaktionen von [Cp★Ru(OMe)]2." Journal of Organometallic Chemistry 438, no. 3 (October 1992): 309–17. http://dx.doi.org/10.1016/0022-328x(92)83414-d.

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23

Gravel, Judith S., and Ina F. Wallace. "Effects of Otitis Media With Effusion on Hearing in the First 3 Years of Life." Journal of Speech, Language, and Hearing Research 43, no. 3 (June 2000): 631–44. http://dx.doi.org/10.1044/jslhr.4303.631.

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Hearing sensitivity was examined prospectively in young children as a function of otitis media with effusion (OME) status in Years 1, 2, and 3. Hearing and OME status were sampled bimonthly from 5 to 36 months of age. Behavioral thresholds were obtained at 4 test frequencies (500, 1000, 2000, and 4000 Hz) using visual reinforcement audiometry and conditioned play audiometry techniques. The majority of children's audiograms were obtained using a computer-controlled test procedure. Thresholds for the test frequencies were averaged for each visit and then averaged across all visits in each year. Reference values were developed for infants and children in Years 1, 2, and 3 who were OME free. Results reveal that children who were classified as bilaterally OME positive in Years 1, 2, and 3 had significantly poorer hearing than children classified as bilaterally OME free in each of these time periods. There was no difference in hearing as a function of gender, socioeconomic status, or birth-risk status.

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24

Giardina-Papa, Daniela, Francesco Paolo Intini, Giovanni Natile, and Concetta Pacifico. "trans-Chloridobis[(Z)-1-imino-1-methoxyethane-κN](triphenylphosphane-κP)platinum(II) chloride monohydrate." Acta Crystallographica Section C Crystal Structure Communications 68, no. 11 (October 18, 2012): m300—m302. http://dx.doi.org/10.1107/s0108270112040826.

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The title compound, [PtCl(C3H7NO)2(C18H15P)]Cl·H2O ortrans-[PtCl{Z-HN=C(Me)OMe}2(PPh3)]Cl·H2O, crystallizes from an acetone solution of isomerictrans-[PtCl{E-HN=C(Me)OMe}2(PPh3)]Cl. The two HN=C(Me)OMe ligands show typical π-bond delocalization over the N—C—O group [Cini, Caputo, Intini & Natile (1995).Inorg. Chem.34, 1130–1137] and have the unprecedentedZ–anticonfiguration. The relative orientation of the imino ether ligands is head-to-tail.

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25

Giri, Rajat Subhra, and Bhubaneswar Mandal. "Unique crystallographic signatures of Boc-Gly-Phe-Phe-OMe and Boc-Gly-Phg-Phe-OMe and their self-association." CrystEngComm 21, no. 2 (2019): 236–43. http://dx.doi.org/10.1039/c8ce01723a.

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26

Sillanpää, J. Kirsikka, Henrik Sundh, and Kristina S. Sundell. "Calcium transfer across the outer mantle epithelium in the Pacific oyster, Crassostrea gigas." Proceedings of the Royal Society B: Biological Sciences 285, no. 1891 (November 14, 2018): 20181676. http://dx.doi.org/10.1098/rspb.2018.1676.

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Calcium transport is essential for bivalves to be able to build and maintain their shells. Ionized calcium (Ca 2+ ) is taken up from the environment and eventually transported through the outer mantle epithelium (OME) to the shell growth area. However, the mechanisms behind this process are poorly understood. The objective of the present study was to characterize the Ca 2+ transfer performed by the OME of the Pacific oyster, Crassostrea gigas, as well as to develop an Ussing chamber technique for the functional assessment of transport activities in epithelia of marine bivalves. Kinetic studies revealed that the Ca 2+ transfer across the OME consists of one saturable and one linear component, of which the saturable component fits best to Michaelis–Menten kinetics and is characterized by a K m of 6.2 mM and a V max of 3.3 nM min −1 . The transcellular transfer of Ca 2+ accounts for approximately 60% of the total Ca 2+ transfer across the OME of C. giga s at environmental Ca 2+ concentrations. The use of the pharmacological inhibitors: verapamil, ouabain and caloxin 1a1 revealed that voltage-gated Ca 2+ -channels, plasma-membrane Ca 2+ -ATPase and Na + /Ca 2+ -exchanger all participate in the transcellular Ca 2+ transfer across the OME and a model for this Ca 2+ transfer is presented and discussed.

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27

Liu, Congcong, Yuxia Liu, Yanan Tang, Haosheng Liang, and Siwei Bi. "Mechanisms and origins of the switchable regioselectivity of FeBr3-catalyzed [1,2]-aryl and [1,2]-alkyl shifts of α-aryl aldehydes." Organic & Biomolecular Chemistry 14, no. 8 (2016): 2522–36. http://dx.doi.org/10.1039/c6ob00001k.

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With the aid of DFT calculations, the FeBr₃-catalyzed skeletal rearrangements of 2-cyclohexanal,2-p-C₆H₄OMe-propylaldehyde (1A) and 2-phenyl,2-p-C₆H₄OMe-propylaldehyde (1B) were investigated theoretically.

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28

Hokke, Cornelis H., Jos G. M. van der Ven, Johannis P. Kamerling, and Johannes F. G. Vliegenthart. "Action of rat liver Galβ1-4GlcNAc α(2-6)-sialyltransferase on Manβ1-4GlcNAcβ-OMe, GalNAcβ1-4GlcNAcβ-OMe, Glcβ1-4GlcNAcβ-OMe and GlcNAcβ1-4GlcNAcβ-OMe as synthetic substrates." Glycoconjugate Journal 10, no. 1 (February 1993): 82–90. http://dx.doi.org/10.1007/bf00731191.

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29

Thiele, D. L., and P. E. Lipsky. "Apoptosis is induced in cells with cytolytic potential by L-leucyl-L-leucine methyl ester." Journal of Immunology 148, no. 12 (June 15, 1992): 3950–57. http://dx.doi.org/10.4049/jimmunol.148.12.3950.

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Abstract Previous studies have demonstrated that the selective toxicity of leucyl-leucine methyl ester (Leu-Leu-OMe) for cytotoxic lymphocytes and myeloid cells is dependent on intracellular conversion to membranolytic metabolites by the acyl transferase activity of the granule enzyme dipeptidyl peptidase I (DPPI) that is enriched in these cells. The mechanism of cell death remained unclear, however, and was the subject of the experiments reported here. When human U937, HL60, or THP-1 myeloid tumor cell lines or murine CTLL-2 cells were treated with Leu-Leu-OMe, early release of both cytosolic 51Cr and soluble [3H]TdR labeled DNA fragments was observed, whereas antibody + C treatment of these cells caused only 51Cr release. Killing of U937 or THP-1 cells by incubation with the lysosomotropic amino acid methyl ester, Phe-OMe also induced only 51Cr release without evidence of DNA fragmentation. Preincubation with Zn2+, a known inhibitor of endonuclease activity prevented Leu-Leu-OMe-induced 51Cr or [3H]TdR release from these cell lines, but had no effect on antibody + C or Phe-OMe-induced 51Cr release. Zn2+ also prevented Leu-Leu-OMe-mediated killing of normal human CD16+ NK cells. Zn2+ had no inhibitory effect on Leu-Leu-OMe uptake or intracellular conversion to (Leu-Leu)n-OMe metabolites by these cell lines. Moreover, Zn2+ did not inhibit 51Cr release from nonnucleated E or nucleated U937 targets induced by extracellular production of DPPI-generated metabolites of Leu-Leu-OMe. Thus, killing of cytotoxic lymphocytes and myeloid cells by Leu-Leu-OMe appears to be dependent on generation of metabolites with membranolytic properties, but cell death induced by this process does not involve simple lysis of the plasma membrane. Rather, intracellular production of DPPI generated (Leu-Leu)n-OMe metabolites appears to trigger, an additional Zn(2+)-sensitive process that is associated with induction of apoptosis in cells with cytolytic potential.

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Delgado-Martínez, Patricia, Luis Moreno-Martínez, Rodrigo González-Prieto, Santiago Herrero, José L. Priego, and Reyes Jiménez-Aparicio. "Steric, Activation Method and Solvent Effects on the Structure of Paddlewheel Diruthenium Complexes." Applied Sciences 12, no. 3 (January 19, 2022): 1000. http://dx.doi.org/10.3390/app12031000.

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Conventional heating and solvothermal synthetic methods (with or without microwave activation) have been used to study the reaction of o-, m- and p-methoxybenzoic acid with [Ru2Cl(μ-O2CMe)4]. The tetrasubstituted series [Ru2Cl(µ-O2CC6H4-R)4], with R = o-OMe, m-OMe and p-OMe, has been prepared by the three procedures. Depending on the synthetic method and the experimental conditions, three compounds have been isolated (1a, 1b, 1c) with the o-methoxybenzoate ligand. However, with the m- and p-methoxybenzoate ligands, only the complexes 2 and 3 have been obtained, respectively. Compound 1a, with stoichiometry [Ru2Cl(µ-O2CC6H4-o-OMe)4]n, shows a polymeric structure with the chloride ions bridging the diruthenium units to form linear chains. Compounds 2 and 3, with the same stoichiometry, predictably form zig-zag chains in accordance with their insolubility and their magnetic measurements. Compound 1b, [Ru2Cl(µ-O2CC6H4-o-OMe)4(EtOH)], is a discrete molecular species with a chloride ion and one ethanol molecule occupying the axial positions of the dimetallic unit. Compound 1c is a cation-anion complex, [Ru2(µ-O2CC6H4-o-OMe)4(MeOH)2][Ru2Cl2(µ-O2CC6H4-o-OMe)4]. The cationic complex has two solvent molecules at the axial positions whereas the anionic complex has two chloride ligands at these positions. Complexes have been characterized by elemental analyses, mass spectrometry and IR and UV-vis-NIR spectroscopies. A magnetic study of complexes 1a, 1b, 2 and 3 have also been carried out. The crystal structure of compounds 1b and 1c have been solved by single X-ray crystal methods.

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Ganbo, T., K. I. Hisamatsu, H. Inoue, K. Kikushima, A. Mizukoshi, and Y. Murakami. "Detection of soluble interleukin-2 receptor and soluble intercellular adhesion molecule-1 in the effusion of otitis media with effusion." Mediators of Inflammation 4, no. 5 (1995): 350–54. http://dx.doi.org/10.1155/s0962935195000561.

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We measured sIL-2R, TNF-α and sICAM-1 in the sera and middle ear effusions (MEEs) of patients with otitis media with effusion (OME). Although there was no signmcant difference between the sIL-2R levels of the serous and mucoid MEEs, they were significantly higher than serum sIL-2R levels of OME patients and healthy controls. TNF-α levels of the mucoid MEEs were significantly higher than those of the serous type. However, TNF-α was rarely detected in the sera of OME patients or healthy controls. We observed significant differences between the serous and mucoid MEEs with respect to their sICAM-1 levels, which were also higher than serum slCAM-1 levels of OME patients and healthy controls. Our findings suggested that IL-2, TNF-α and ICAM-1 could be significantly involved in the pathogenesis of OME through the cytokine network.

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Shihada, Abdel-Fattah, and Frank Weller. "Crystal Structures of [Bu2Sn(O2PPh2)2], [Ph2Sn(O2PPh2)2], and [PhClSn(O2PPh2)OMe]2. Raman Spectra of [Ph2Sn(O2PPh2)2] and [PhClSn(O2PPh2)OMe]2." Zeitschrift für anorganische und allgemeine Chemie 632, no. 14 (October 2006): 2238–43. http://dx.doi.org/10.1002/zaac.200600137.

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SANCAKTAR, Özlem, Abdullah Alper ÖZ, and Mehmet Eser SANCAKTAR. "Does maxillary expansion improve hearing loss due to otitis media with effusion?" Journal of Experimental and Clinical Medicine 38, no. 2 (March 14, 2021): 159–66. http://dx.doi.org/10.52142/omujecm.38.2.19.

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Some authors emphasized that maxillary expansion had a positive effect on impaired hearing due to otitis media with effusion (OME). The goal of this study was to compare the improvement of hearing loss degrees of patients treated with rapid maxillary expansion (RME) and patients watched for spontaneous resolution. This study was conducted with audiometric and tympanometric records of 22 patients with OME. Group 1 consisted of patients who had OME and needed RME (n=12), and group 2 consisted of patients who had OME and were observed for spontaneous resolution (n=10). In-group 1, records were taken before expansion (T0), just after RME (T1), after the retention period (T2), and 6 months after expansion (T3). In-group 2, T0 and T2 records were taken. In-group 1, hearing levels improved and air-bone gaps (ABG) decreased significantly after RME (p<0.05). This improvement showed a relapse with T2 and T3 records. In-group 2, no significant change was observed in hearing levels but ABG levels decreased significantly (p<0.05). The extent of healing level was not significantly different between the maxillary expansion and control groups when T2-T0 records were compared. The results of this study indicated that RME improved hearing levels and decreased ABG after expansion in children with OME; however, a relapse occurred after the retention. ABG levels in both groups exhibited similar decreases after retention. RME, although it is not a major treatment for OME, it can be said that it has positive effects for OME when applied within orthodontic indication.

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Zhu, Xiao-Quan, Wen-Hai Cao, Shao-Dong Su, Xin-Tao Wu, and Tian-Lu Sheng. "Effects of ligand substituents on the single-molecule magnetic behavior of quinonoid-bridged dicobalt compounds." Dalton Transactions 49, no. 20 (2020): 6738–43. http://dx.doi.org/10.1039/d0dt00033g.

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The SMM behavior weakens until its disappearance with the substituent changing from Br, H to OMe in the quinonoid-bridged dicobalt compounds [(N₄Co)₂LX](ClO₄)₂, (X = H, Cl, Br, and OMe).

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Georgiadou, Michaella, Melina Christou, Kleitos Sokratous, Jesper Wengel, Kyriaki Michailidou, Kyriacos Kyriacou, Andrie Koutsoulidou, Nikolaos P. Mastroyiannopoulos, and Leonidas A. Phylactou. "Intramuscular Evaluation of Chimeric Locked Nucleic Acid/2′OMethyl-Modified Antisense Oligonucleotides for Targeted Exon 23 Skipping in Mdx Mice." Pharmaceuticals 14, no. 11 (October 30, 2021): 1113. http://dx.doi.org/10.3390/ph14111113.

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Duchenne muscular dystrophy (DMD) is a fatal disorder characterised by progressive muscle wasting. It is caused by mutations in the dystrophin gene, which disrupt the open reading frame leading to the loss of functional dystrophin protein in muscle fibres. Antisense oligonucleotide (AON)-mediated skipping of the mutated exon, which allows production of a truncated but partially functional dystrophin protein, has been at the forefront of DMD therapeutic research for over two decades. Nonetheless, novel nucleic acid modifications and AON designs are continuously being developed to improve the clinical benefit profile of current drugs in the DMD pipeline. We herein designed a series of 15mer and 20mer AONs, consisting of 2′O-Methyl (2′OMe)- and locked nucleic acid (LNA)-modified nucleotides in different percentage compositions, and assessed their efficiency in inducing exon 23 skipping and dystrophin restoration in locally injected muscles of mdx mice. We demonstrate that LNA/2′OMe AONs with a 30% LNA composition were significantly more potent in inducing exon skipping and dystrophin restoration in treated mdx muscles, compared to a previously tested 2′OMe AON and LNA/2′OMe chimeras with lower or higher LNA compositions. These results underscore the therapeutic potential of LNA/2′OMe AONs, paving the way for further experimentation to evaluate their benefit-toxicity profile following systemic delivery.

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Tao, Qi, Xiao Zhang, Liping Jing, Lu Sun, and Peipei Dang. "Construction of Ketoenamine-Based Covalent Organic Frameworks with Electron-Rich Sites for Efficient and Rapid Removal of Iodine from Solution." Molecules 28, no. 24 (December 18, 2023): 8151. http://dx.doi.org/10.3390/molecules28248151.

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Porous covalent organic frameworks (COFs) have been widely used for the efficient removal of iodine from solution due to their abundance of electron-rich sites. In this study, two kinds of ketoenamine-based COFs, TpBD-(OMe)2 and TpBD-Me2, are successfully synthesized via Schiff base reaction under solvothermal conditions using 1, 3, 5-triformylphoroglucinol as aldehyde monomer, o-tolidine and o-dianisidine as amino monomers. The ability of TpBD-(OMe)2 and TpBD-Me2 to adsorb iodine in cyclohexane or aqueous solutions has been quantitatively analyzed and interpreted in terms of adsorption sites. TpBD-Me2 possesses two adsorption sites, -NH- and -C=O, and exhibits an adsorption capacity of 681.67 mg/g in cyclohexane, with an initial adsorption rate of 0.6 g/mol/min with respect to COF unit cell. The adsorption capacity of TpBD-(OMe)2 can be as high as 728.77 mg/g, and the initial adsorption rate of TpBD-(OMe)2 can reach 1.2 g/mol/min in the presence of oxygen atoms between the methyl group and the benzene ring. Compared with TpBD-Me2, the higher adsorption capacity and adsorption rate of TpBD-(OMe)2 towards iodine are not only reflected in organic solvents, but also in aqueous solutions. It is proven through X-ray photoelectron spectroscopy and Raman spectroscopy that iodine exists in the form of I2, I3−, and I5− within TpBD-(OMe)2 and TpBD-Me2 after adsorption. This work not only expands the application of COFs in the field of iodine adsorption, but also provides research ideas and important an experimental basis for the optimization of iodine adsorption sites.

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Nozawa, Takeshi, Toshiaki Kobayashi, Tomohiro Matsumoto, Fujio Yagihashi, Kazuhiko Sato, and Masayasu Igarashi. "Treating octasilanol [Si8O12][OH]8 with tetramethoxysilane and trimethoxyvinylsilane: a halogen-free synthetic route to alkoxysilyl-substituted double-four-ring siloxanes." Dalton Transactions 50, no. 5 (2021): 1594–98. http://dx.doi.org/10.1039/d0dt04265j.

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Giri, Rajat Subhra, and Bhubaneswar Mandal. "Formation of supramolecular single and double helix-like structures from designed tripeptides." CrystEngComm 21, no. 37 (2019): 5618–25. http://dx.doi.org/10.1039/c9ce01168d.

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Paz, Márcia Fernanda Correia Jardim, Marcus Vinícius Oliveira Barros de Alencar, Rodrigo Maciel Paulino de Lima, André Luiz Pinho Sobral, Glauto Tuquarre Melo do Nascimento, Cristiane Amaral dos Reis, Maria do Perpetuo Socorro de Sousa Coêlho, et al. "Pharmacological Effects and Toxicogenetic Impacts of Omeprazole: Genomic Instability and Cancer." Oxidative Medicine and Cellular Longevity 2020 (March 29, 2020): 1–21. http://dx.doi.org/10.1155/2020/3457890.

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Omeprazole (OME) is commonly used to treat gastrointestinal disorders. However, long-term use of OME can increase the risk of gastric cancer. We aimed to characterize the pharmacological effects of OME and to correlate its adverse effects and toxicogenetic risks to the genomic instability mechanisms and cancer-based on database reports. Thus, a search (till Aug 2019) was made in the PubMed, Scopus, and ScienceDirect with relevant keywords. Based on the study objective, we included 80 clinical reports, forty-six in vitro, and 76 in vivo studies. While controversial, the findings suggest that long-term use of OME (5 to 40 mg/kg) can induce genomic instability. On the other hand, OME-mediated protective effects are well reported and related to proton pump blockade and anti-inflammatory activity through an increase in gastric flow, anti-inflammatory markers (COX-2 and interleukins) and antiapoptotic markers (caspases and BCL-2), glycoprotein expression, and neutrophil infiltration reduction. The reported adverse and toxic effects, especially in clinical studies, were atrophic gastritis, cobalamin deficiencies, homeostasis disorders, polyp development, hepatotoxicity, cytotoxicity, and genotoxicity. This study highlights that OME may induce genomic instability and increase the risk of certain types of cancer. Therefore, adequate precautions should be taken, especially in its long-term therapeutic strategies and self-medication practices.

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Carballeira, Néstor M., Michelle Cartagena, Fengyu Li, Zhongfang Chen, Christopher F. Prada, Estefania Calvo-Alvarez, Rosa M. Reguera, and Rafael Balaña-Fouce. "First total synthesis of the (±)-2-methoxy-6-heptadecynoic acid and related 2-methoxylated analogs as effective inhibitors of the Leishmania topoisomerase IB enzyme." Pure and Applied Chemistry 84, no. 9 (April 30, 2012): 1867–75. http://dx.doi.org/10.1351/pac-con-11-10-21.

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The fatty acids (±)-2-methoxy-6Z-heptadecenoic acid, (±)-2-methoxy-6-hepta-decynoic acid, and (±)-2-methoxyheptadecanoic acid were synthesized and their inhibitory activity against the Leishmania DNA topoisomerase IB enzyme (LdTopIB) determined. Both 2-OMe-17:1 fatty acids were synthesized from 4-bromo-1-pentanol, the olefinic fatty acid in 10 steps and in 7 % overall yield, while the acetylenic fatty acid in 7 steps and in 14 % overall yield. The 2-OMe-17:0 acid was prepared in 6 steps and in 42 % yield from 1-hexa-decanol. The 2-OMe-17:1 acids inhibited LdTopIB, with the acetylenic acid displaying an EC50 = 16.6 ± 1.1 μM, but the 2-OMe-17:0 acid did not inhibit LdTopIB. The (±)-2-methoxy-6Z-heptadecenoic acid preferentially inhibited LdTopIB over the human TopIB enzyme. Unsaturation seems to be a prerequisite for effective inhibition, rationalized in terms of weak intermolecular interactions between the active site of LdTopIB and either the double or triple bonds of the fatty acids. Toxicity toward Leishmania donovani promastigotes was also investigated, resulting in the order acetylenic > olefinic > saturated with the (±)-2-methoxy-6-heptadecynoic acid displaying an EC50 = 74.0 ± 17.1 μM. Our results indicate that α-methoxylation decreases the toxicity of C17:1 fatty acids toward L. donovani promastigotes, but improves their selectivity index.

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41

Zhang, Fenbao, Michael E. Broczkowski, Michael C. Jennings, and Richard J. Puddephatt. "Oxidative addition chemistry of dimethyl(dipyridyl ketone)platinum(II)." Canadian Journal of Chemistry 83, no. 6-7 (June 1, 2005): 595–605. http://dx.doi.org/10.1139/v05-028.

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The dimethylplatinum(II) complex [PtMe2(DPK)] (DPK = di-2-pyridyl ketone) undergoes easy oxidative addition to give platinum(IV) complexes. For example, reaction of [PtMe2(DPK)] with MeI gave [PtIMe3(DPK)], reaction with N-chlorosuccinimide in methanol gave [PtCl(OMe)Me2(DPK)], and reaction with [FN(CH2CH2)2NCH2Cl][BF4]2 in MeCN gave [PtF(NCMe)Me2(DPK)][BF4]. In several cases, the ketone group of the DPK ligand took part in the reactions. For example, oxidation of [PtMe2(DPK)] by air or hydrogen peroxide gave [Pt(OH)Me2(DPKOH)] (DPKOH = κ3-NN′O-(2-C5H4N)2C(OH)O), which reacted with HCl to give [PtClMe2(DPKOH)] or with excess acetyl chloride to give [PtCl2Me2(DPK)]. Reaction of [PtMe2(DPK)] with methyl triflate in MeCN solution gave [PtMe3(NCMe)(DPK)][OTf], which reacted with more MeOTf in the presence of base to give [PtMe3{DPC(OMe)2}][OTf], where DPC(OMe)2 = κ3-NN′O-(2-C5H4N)2C(OMe)2. Hydrolysis of [PtF(NCMe)Me2(DPK)][BF4] gave [Pt{NHC(=O)Me}Me2(DPKOH)], which crystallized in partially protonated form as an unusual supramolecular polymer [Pt{NHC(=O)Me}Me2(DPKOH)]·0.5HBF4.Key words: platinum, oxidative addition, ketone, pyridyl.

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42

Itazaki, Masumi, Yuka Shigesato, and Hiroshi Nakazawa. "Synthesis, characterization, and crystal structure of cis-[Pt(Me)2{PPh2(OMe)}2] and the conversion into cis-[Pt(OH2)2{PPh2(OMe)}2][OTf]2." Heteroatom Chemistry 22, no. 3-4 (2011): 371–76. http://dx.doi.org/10.1002/hc.20692.

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43

Chen, Qin, Lidun Ma, Shuncheng Liu, and Jon Zubieta. "Structural characterization of the pentamolybdate anion, [(MoO4)2{Mo3O8(OMe)}]-3, and isolation of the [Mo3O8(OMe)]+ trinuclear core in the squarate complex [{Mo3O8(OMe)}(C4O4)2]3-." Journal of the American Chemical Society 111, no. 15 (July 1989): 5944–46. http://dx.doi.org/10.1021/ja00197a067.

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44

Wagler, Jörg, and Gerhard Roewer. "Syntheses of Allyl- and 3-Silylpropyl-substituted Salen-like Tetradentate Ligands via Hypercoordinate Silicon Complexes." Zeitschrift für Naturforschung B 61, no. 11 (November 1, 2006): 1406–12. http://dx.doi.org/10.1515/znb-2006-1114.

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The reaction of allylchlorosilanes (AllSiCl3, AllSiPhCl2) with the tetradentate salen-like ligand 1, o-HO-p-MeO-C6H3-C(Ph)=N-(CH2)2-N=C(Ph)-C6H3-p-OMe-o-OH, yields pentacoordinate silicon complexes of an allyl-substituted ligand system (o-O-p-MeO-C6H3-C(Ph)=N-(CH2)2- N-C(Ph,All)-C6H3-p-OMe-o-O)SiR (2a: R = Ph, 3: R = Cl). The allyl shift step involved in the formation of 2a and 3 probably occurs via an intermediate hexacoordinate silicon complex. This reaction is diastereoselective. The missing diastereomer of 2 (2b) was prepared using an alternative synthesis route, which starts from the trimethylsilyl derivative of ligand 1 o-Me3SiO-p-MeO-C6H3-C(Ph)=N- (CH2)2-N=C(Ph)-C6H3-p-OMe-o-OSiMe3. The diastereomers of 2 obtained from modified reaction pathways give rise to suggestions about the mechanism of formation of these complexes. Further functionalization of the allyl-substituted ligand system of 3 was carried out by hydrosilylation with HSiCl3 to yield complex 4 (o-O-p-MeO-C6H3-C(Ph)=N-(CH2)2-N-C(Ph)[(CH2)3-SiCl3]- C6H3-p-OMe-o-O)SiCl.

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45

de Araújo, Erisvaldo Amarante, Fernando Sabia Tallo, Alex Sandro Felisberto Oliveira, Gustavo Saad Silva El Toghlobi, Rafael Augusto Arantes, Rafael Balsimelli, Bruno Kehrwald-Balsimelli, et al. "Cardiotoxic Effects Produced by Omeprazole and Methylene Blue in an Animal Model of Cardiac Ischemia and Reperfusion and Potential Implications for the Pharmacological Strategy for Vasoplegic Syndrome." Biomedicines 12, no. 3 (March 6, 2024): 582. http://dx.doi.org/10.3390/biomedicines12030582.

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Defined as systemic hypotension caused by intense vasodilation due to the loss of systemic vascular resistance, vasoplegic syndrome (VS) is associated with elevated morbidity and mortality in humans. Although vasopressors such as norepinephrine and vasopressin are the first-choice drugs for VS treatment, several other drugs such as methylene blue (MB) can be used as adjuvant therapy including rescue therapy. To develop new pharmacological strategies to reduce the risk of VS, we investigated the effects of treatments with MB (2 mg/kg/IV), omeprazole (OME, 10 mg/kg/IV), and their combination in an animal model of cardiac ischemia–reperfusion (CIR). The ventricular arrhythmia (VA), atrioventricular block (AVB), and lethality (LET) incidence rates caused by CIR (evaluated via ECG) and serum levels of the cardiac lesion biomarkers creatine kinase–MB (CK-MB) and troponin I (TnI) in adult rats pretreated with saline solution 0.9% and submitted to CIR (SS + CIR group) were compared to those pretreated with MB (MB + CIR group), OME (OME + CIR group), or the MB + OME combination (MB + OME + CIR group). The AVB and LET incidence rates in the MB + CIR (100%), OME + CIR (100%), and MB + OME + CIR (100%) groups were significantly higher compared to the SS + CIR group (60%). The serum level of CK-MB in these groups were also significantly higher compared to the SS + CIR group, demonstrating that the treatments before CIR with MB, OME, and MB + OME produced similar effects in relation to cardiac function and the occurrence of lesions. These results demonstrate that the treatment of animals subjected to the CIR protocol with OME produced the same effects promoted by the treatment with MB, which may suggest the possibility of using OME alone or in combination with MB in medical clinics in treatment of VS.

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46

Frontain, Raymond-Jean. "Kipling's"Follow Me 'Ome"and 2 Samuel 1." ANQ: A Quarterly Journal of Short Articles, Notes and Reviews 22, no. 2 (April 2009): 37–48. http://dx.doi.org/10.3200/anqq.22.2.37-48.

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47

Kosman, Joanna, and B. Juskowiak. "2’-OMe-RNA Analogues of Peroxidase-mimicking DNAzymes." Procedia Engineering 168 (2016): 626–29. http://dx.doi.org/10.1016/j.proeng.2016.11.230.

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48

Champness, N. R., A. M. Hopkins, and G. Reid. "trans-[Mo(CO)4{P(OMe)3}2]." Acta Crystallographica Section C Crystal Structure Communications 52, no. 4 (April 15, 1996): 797–99. http://dx.doi.org/10.1107/s010827019501479x.

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49

Koelle, Ulrich. "The Tentacular Chemistry of [Cp*Ru(OMe)]2‡." Chemical Reviews 98, no. 4 (June 1998): 1313–34. http://dx.doi.org/10.1021/cr960363a.

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50

Held, Maximilian, Yannic Tönges, Dominik Pélerin, Martin Härtl, Georg Wachtmeister, and Jakob Burger. "On the energetic efficiency of producing polyoxymethylene dimethyl ethers from CO2 using electrical energy." Energy & Environmental Science 12, no. 3 (2019): 1019–34. http://dx.doi.org/10.1039/c8ee02849d.

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Polyoxymethylene dimethyl ether (OME) are a high-potential and carbon-neutral synthetic e-fuel. This is the first comprehensive study to report the energetic efficiency of the production of OME from CO₂ and electrical energy.

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Journal articles on the topic '2'OME'

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