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[formula: see text] Apoptolidin (1) is a novel oncolytic lead that induces apoptosis in transformed cell lines with exceptional selectivity. We report the isolation and characterization of a ring-expanded macrolide isomer of apoptolidin: isoapoptolidin (2). The solution conformation of isoapoptolidin is described. The rate of isomerization was measured under biologically relevant conditions and found to approach equilibrium within the time frame of most cell-based assays. Isoapoptolidin's ability to inhibit mitochondrial F0F1-ATPase is over 10-fold less than that of apoptolidin. 相似文献
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Oxidative cleavage of the C-20/C-21 bond in apoptolidin (1) provides two fragments of similar complexity, facilitating a divide-and-diversify strategy for the determination of the structural basis for apoptolidin's biological activity, the remarkably selective induction of apoptosis in sensitive cell lines. The ability of compounds derived from this cleavage to inhibit mitochondrial F(0)F(1)-ATPase is reported. [structure: see text] 相似文献
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Here we report a cavitand with a photochemical switch as one of the container walls. The azo-arene switch undergoes photoisomerization when subjected to UV light producing a self-fulfilled cavitand. This process is thermally and photochemically reversible. The reported cavitand binds small molecules and these guests can be ejected from the cavitand through this photochemical process. 相似文献
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Orion Ciftja 《Physics letters. A》2010,374(7):981-767
The most popular model for a two-dimensional electronic system considers electrons moving in a background of uniform positive charge. Studies of finite systems employing a spherical geometry (electrons on the surface of a sphere) or a disk geometry background are numerous. The same cannot be said for a square geometry, who after all, would be the geometry of choice for quantum Hall states in a Landau gauge. A background represented by a uniformly charged square seems to be perceived as too costly from a computational point of view. By using simple transformations, we show that the Coulomb self-energy and the electrostatic potential of a uniformly charged square can be exactly calculated and poses no difficulty. The current results can be used in systematic studies of properties of finite systems of electrons embedded in a positive background in the form of a uniformly charged square. 相似文献
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[structure: see text] Apoptolidin (1) exhibits potent and highly selective apoptosis inducing activity against sensitive cancer cell lines and is hypothesized to act by inhibition of mitochondrial F(0)F(1)-ATP synthase. A series of apoptolidin derivatives, including a new intermolecular Diels-Alder adduct, were analyzed for antiproliferative activity in E1A-transformed rat fibroblasts. Potent F(0)F(1)-ATPase inhibition was not a sufficient determinant of antiproliferative activity for several analogues, suggesting the existence of a secondary biological target or more complex mode of action for apoptolidin. 相似文献
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Daniel Decato Michael Jahnke Orion Berryman 《Acta Crystallographica. Section C, Structural Chemistry》2023,79(9):344-352
Three conformational polymorphs of 3-(azidomethyl)benzoic acid, C8H7N3O2, are reported. All three structures maintain similar carboxylic acid dimers and π–π stacking. Crystal structure analysis and computational evaluations highlight the azidomethyl group as a source of conformational polymorphism, thus having potential implications in the design of solid-state reactions. 相似文献
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E. Colineau A. Hen J.-P. Sanchez J.-C. Griveau N. Magnani R. Eloirdi I. Halevy P. Gaczyński I. Orion A. B. Shick R. Caciuffo 《Hyperfine Interactions》2016,237(1):80
Rare-earth-based compounds R2T17 (R=Rare earth; T=Transition metal) have been extensively studied and developed for applications as permanent magnets. The actinide-based analogues, however, are much less documented and we report here about the magnetic properties of Np2Co17 and Np2Ni17, as inferred from 237Np Mössbauer spectroscopy, the best resonance in actinides, and specific heat. 相似文献
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Cangelosi VM Sather AC Zakharov LN Berryman OB Johnson DW 《Inorganic chemistry》2007,46(22):9278-9284
The As-pi interaction, in conjunction with reversible As-thiolate bond formation, is used to direct the self-assembly of dinuclear As2L2Cl2 (L = a dithiolate) macrocycles that exist as equilibrium mixtures of both syn and anti diastereomers. The diastereomeric excess of these self-assembly reactions is controlled in a predictable manner by prudent choice of different achiral, isomeric ligands. A general method for the preparation of As2L2Cl2 macrocycles is established, and strategies to control the diastereoselective self-assembly of regioisomeric macrocycles in solution and the crystalline state are described. A mechanism for the interconversion between diastereomers (a slow process on the NMR time scale) is suggested, and variable-temperature NMR spectroscopic data show that the diastereomeric excess (de) decreases with increasing temperature. anti-As2(L2,6)2Cl2 crystallizes in monoclinic space group P2(1)/n with a = 6.3949(13), b = 19.675(4), c = 10.967(2) A, beta = 106.817(3) degrees , and Z = 2. anti-As2(L1,5)2Cl2 crystallizes in monoclinic space group P2(1)/c with a = 6.813(4), b = 19.085(12), c = 10.277(6) A, beta = 107.788(10) degrees , and Z = 4. syn-As2(L1,4)2Cl2.CHCl3 crystallizes in triclinic space group P(-) with a = 19.313(4), b = 19.923(4), c = 24.508(5) A, alpha = 78.110(4) degrees , beta = 78.860(5) degrees , gamma = 89.183(5) degrees , and Z = 12. As2(L1,4)2Cl2.C6H6 crystallizes in monoclinic space group P2(1)/n with a = 10.3332(7), b = 34.375(2), c = 17.8593(12) A, beta = 98.9650(10) degrees , and Z = 8. 相似文献