A ferrocene containing o-aminoanilide, N1-(2-aminophenyl)-N8-ferrocenyloctanediamide (2b, Pojamide) displayed nanomolar potency vs HDAC3. In comparison to RGFP966, a potent and selective HDAC3 inhibitor, Pojamide displayed superior activity in HCT116 colorectal cancer cell invasion assays; however, TCH106 and romidepsin, potent HDAC1 inhibitors, outperformed Pojamide in cellular proliferation and colony formation assays. Together, these data suggest that HDAC1,3 inhibition is desirable to achieve maximum anticancer benefits. Additionally, we explored Pojamide-induced redox pharmacology. Indeed, treating HCT116 cells with Pojamide, SNP (sodium nitroprusside), and glutathione (GSH) led to greatly enhanced cytotoxicity and DNA damage, attributed to activation to an Fe(III) species.
The chytrid fungus Batrachochytrium dendrobatidis (Bd) is notorious amongst current conservation biology challenges, responsible for mass mortality and extinction of amphibian species. World trade in amphibians is implicated in global dissemination. Exports of South African Xenopus laevis have led to establishment of this invasive species on four continents. Bd naturally infects this host in Africa and now occurs in several introduced populations. However, no previous studies have investigated transfer of infection into co-occurring native amphibian faunas. A survey of 27 U.K. institutions maintaining X. laevis for research showed that most laboratories have low-level infection, a risk for native species if animals are released into the wild. RT-PCR assays showed Bd in two introduced U.K. populations of X. laevis, in Wales and Lincolnshire. Laboratory and field studies demonstrated that infection levels increase with stress, especially low temperature. In the U.K, native amphibians may be exposed to intense transmission in spring when they enter ponds to spawn alongside X. laevis that have cold-elevated Bd infections. Exposure to cross-infection has probably been recurrent since the introduction of X. laevis, >20 years in Lincolnshire and 50 years in Wales. These sites provide an important test for assessing the impact of X. laevis on Bd spread. However, RT-PCR assays on 174 native amphibians (Bufo, Rana, Lissotriton and Triturus spp.), sympatric with the Bd-infected introduced populations, showed no foci of self-sustaining Bd transmission associated with X. laevis. The abundance of these native amphibians suggested no significant negative population-level effect after the decades of co-occurrence. (C) 2015 The Authors. Published by Elsevier Ltd.
Fragments based on the VEGFR2i Semaxanib (SU5416, (vascular endothelial growth factor receptor-2 inhibitor) and the HDACi (histone deacetylase inhibitor) SAHA (suberanilohydroxamic acid) have been merged to form a range of low molecular weight dual action hybrids. Vindication of this approach is provided by SAR, docking studies, in vitro cancer cell line and biochemical enzyme inhibition data as well as in vivo Xenopus data for the lead molecule (Z)-N1-(3-((1H-pyrrol-2-yl) methylene)-2-oxoindolin-5-yl)N8- hydroxyoctanediamide 6.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
(E)- and (Z)-3-Ferrocenylmethylidene-1,3-dihydro-2H-indol-2-ones 1 have been structurally modified in order to explore SAR against a range of kinases. Of note is the submicromolar to low micromolar inhibition of DYRK3 and 4 by a number of complexes. Screening using Xenopus embryos showed some of the compounds to have potent antiangiogenisis activity.
1,3-Dihydro-2H-indol-2-one (1) undergoes microwave-mediated Knoevenagel condensations with 1,2,3,4,5-pentaphenylferrocene carboxaldehyde (2b) or (eta(4)-tetraphenyl-cyclobutadiene)(eta(5)-cyclopentadienylcarboxaldehyde)cobalt (2c) to afford metallocene-substituted 3-methylidene-1,3-dihydro-2H-indol-2-one 4 or 5, respectively, in excellent yields as separable E,Z-sfereoisomeric mixtures. Both 4 and 5 exhibited poor kinase inhibition and no appreciable cytotoxicity toward a leukemia cell line, attributed to the steric bulk of the metallocene substituents.
The ferrocene analogue 4b had an IC50 = 4 nM (HDAC1), 180 nM (HDAC8) and was effective in a Xenopus model of tubulin deacetylation. Analogue 4a displayed mainly μM IC50 values against HDACs apart from HDAC6 (IC50 = 69 nM).
Poor nuclear entry, especially into nondividing cells, is a limiting factor in nonviral gene delivery. We have engineered a novel chimeric vector relying on the controlled assembly of a TAT-tagged multisubunit DNA binding protein (EcoR124I) with expression plasmids containing the EcoR124I recognition site. Molecular interactions of this molecular assembly were studied by electrophoretic mobility shift assay and atomic force microscopy. Maintenance of nanocomplexes in an appropriate stoichiometric ratio was both necessary and sufficient to produce a significant (>8-fold) increase in the activity of the therapeutic alpha-galactosidase A enzyme after intramuscular administration in the mouse model of Fabry disease. To our knowledge, this is the first molecular targeting system significantly enhancing plasmid-based expression in skeletal muscle. Coinjection with pluronic SP1017 produced further enhancement of gene expression, demonstrating cumulative effects of the increased nuclear delivery by TAT chimeras and transcription activation by the pluronic. Cell penetration peptides (CPP), such as TAT, have been shown to improve delivery of macromolecules, when linked directly. However, in our system TAT-enhanced targeting took place even though it was linked to the plasmid DNA molecule indirectly via two noncovalent bonds. Therefore, this proof-of principle result indicates that TAT (and potentially other CPP) can be used for targeting modular chimeric vectors and therapeutic nanodevices.