Branch Rankin (peacefelony6)
Four water-soluble macrocycles were chosen to explore the photodecomposition behaviours of quaternized 9-alkoxy-substituted anthracene (AnQA). Significantly, a highly charged macrocyclic skeleton leads to extremely close packing among the anthryl rings, providing a favourable hydrophobic environment for singlet oxygen, leading to rapid oxidation to produce the photoproducts under sunlight irradiation.New Zn(ii), Cd(ii) and Hg(ii) complexes of saccharinate (sac) and 2,6-bis(2-benzimidazolyl)pyridine (bzimpy), [Zn(bzimpy)2](sac)2·2H2O (Zn), [Cd(sac)2(bzimpy)] (Cd) and [Hg(sac)2(bzimpy)] (Hg), were prepared and fully characterized by spectroscopic methods and X-ray crystallography. In vitro anticancer screening in A549 (lung), MCF-7 (breast) and HT29 (colon) cell lines showed that Zn was highly cytotoxic against A549 and MCF-7 cells with IC50 values of 1.74 ± 0.06 and 3.15 ± 0.10 μM, respectively, and Hg demonstrated potent cytotoxic activity in MCF-7 cells (8.61 ± 0.98 μM), while Cd and bzimpy exhibited moderate growth inhibitory activities in all of the cell lines. In addition, they showed significantly lower toxicity towards normal human breast epithelial MCF10A cells. Moreover, the complexes exhibited significantly high nuclease activity towards plasmid DNA and their interactions with DNA were assessed by gel electrophoresis and DNA docking. Zn and Hg induced G0/G1 cell arrest and apoptotic cell death detected via typical DNA condensation/fragmentation, annexin V staining and caspase 3/7 activity in A549 and MCF-7 cells. These complexes further caused depolarization of mitochondria and oxidative damage of genomic DNA following excessive production of reactive oxygen species (ROS).In this article, we report the synthesis and use of iminosydnone-based profluorophores as bioorthogonal cleavable linkers for imaging applications. These linkers react with cycloalkynes via subsequent [3+2] cycloaddition and retro Diels-Alder reactions, allowing simultaneous release of two dyes in biological media.Depending on the molar ratio employed, the reaction of ScCl3(thf)3 with Li[CH(SiMe3)2] afforded the bis and tris(alkyl) ate complexes [ScCH(SiMe3)22(μ-Cl)2Li(thf)2]2 and Sc[CH(SiMe3)2]3(μ-Cl)Li(thf)3, respectively, in moderate yields. Treatment of these mixed alkyl/chlorido complexes with MeLi gave the mixed alkyl complexes [ScCH(SiMe3)22(μ-Me)2Li(thf)2]2 and Sc[CH(SiMe3)2]3(μ-Me)Li(thf)3. Aiming at homoleptic Sc[CH(SiMe3)2]3 both of the mixed [CH(SiMe3)2]/Me complexes were treated with AlMe3. Although LiAlMe4 separation occurred, aluminium complex Al[CH(SiMe3)2]Me2(thf) was the only isolable crystalline complex. Ate complexes [ScCH(SiMe3)22(μ-Me)2Li(thf)2]2 and [Sc(CH2SiMe3)4][Li(thf)4] revealed the maximum downfield 45Sc NMR chemical shifts of 888.0 and 933.4 ppm, respectively, reported to date. The synthesis of putative Sc[CH(SiMe3)2]3 was also attempted via the aryloxide route applying complexes Sc(OC6H2tBu2-2,6-Me-4)3 and [Sc(OC6H3iPr2-2,6)3]2 along with Li[CH(SiMe3)2] but the outcome was inconclusive. Instead, a cyclic octamer was found for Li[CH(SiMe3)2] in the solid state.A one-pot reaction is used to make a series of [5]rotaxanes. The protocol involves simultaneous threading-followed-by-stoppering to trap a macrocycle (dibenzo[24]crown-8, DB24C8) on an axle to form a mechanically interlocked molecule (MIM) - in this case a rotaxane - and the condensation of an aldehyde with a pyrrole to form a porphyrin precursor. For each [5]rotaxane, a different combination of recognition site and stoppering group was used; the protonation state of the [5]rotaxane can be used to generate different co-conformational states for each [5]rotaxane making these systems potential multi-state switches for further study in solution or the solid-state.Food matrix interactions with polyphenols can affect their bioavailability and as a consequence may modulate their biological effects. The aim of this study was to determine if the matrix and its processing
