Novel trans-platinum complexes of the histone deacetylase inhibitor valproic acid; synthesis, in vitro cytotoxicity and mutagenicity

The first examples of Pt complexes of the well known anti-epilepsy drug and histone deacetylase inhibitor, valproic acid (VPA), are reported. Reaction of the Pt(II) am(m)ine precursors trans-[PtCl2(NH3)(py)] and trans-[PtCl2(py)2] with silver nitrate and subsequently sodium valproate gave trans-[Pt(VPA−1H)2(NH3)(py)] and trans-[Pt(VPA−1H)2(py)2], respectively. The valproato ligands in both complexes are bound to the Pt(II) centres via the carboxylato functionality and in a monodentate manner. The X-ray crystal structure of trans- [Pt(VPA−1H)2(NH3)(py)] is described. Replacement of the dichlorido ligands in trans-[PtCl2(py)2] and trans- [PtCl2(NH3)(py)] by valproato ligands (VPA−1H) to yield trans-[Pt(VPA−1H)2(py)2] and trans-[Pt(VPA−1H)2 (NH3)(py)] respectively, significantly enhanced cytotoxicity against A2780 (parental) and A2780 cisR (cisplatin resistant) ovarian cancer cells. The mutagenicity of trans-[Pt(VPA−1H)2(NH3)(py)] and trans-[Pt (VPA−1H)2(py)2] was determined using the Ames test and is also reported

Novel trans-platinum complexes of the histone deacetylase inhibitor valproic acid; synthesis, in vitro cytotoxicity and mutagenicity

The first examples of Pt complexes of the well known anti-epilepsy drug and histone deacetylase inhibitor, valproic acid (VPA), are reported. Reaction of the Pt(II) am(m)ine precursors trans-[PtCl2(NH3)(py)] and trans-[PtCl2(py)2] with silver nitrate and subsequently sodium valproate gave trans-[Pt(VPA−1H)2(NH3)(py)] and trans-[Pt(VPA−1H)2(py)2], respectively. The valproato ligands in both complexes are bound to the Pt(II) centres via the carboxylato functionality and in a monodentate manner. The X-ray crystal structure of trans- [Pt(VPA−1H)2(NH3)(py)] is described. Replacement of the dichlorido ligands in trans-[PtCl2(py)2] and trans- [PtCl2(NH3)(py)] by valproato ligands (VPA−1H) to yield trans-[Pt(VPA−1H)2(py)2] and trans-[Pt(VPA−1H)2 (NH3)(py)] respectively, significantly enhanced cytotoxicity against A2780 (parental) and A2780 cisR (cisplatin resistant) ovarian cancer cells. The mutagenicity of trans-[Pt(VPA−1H)2(NH3)(py)] and trans-[Pt (VPA−1H)2(py)2] was determined using the Ames test and is also reported

Methylsulfanyl-Stabilized Rotamers of Cobalt Bis(dicarbollide)

Methylsulfanyl derivatives of cobalt bis(dicarbollide), [8,8â\u80²-(MeS)2-3,3â\u80²-Co(1,2-C2B9H10)2]â\u80\u93, [4,4â\u80²-(MeS)2-3,3â\u80²-Co(1,2-C2B9H10)2]â\u80\u93, and [4,7â\u80²-(MeS)2-3,3â\u80²-Co(1,2-C2B9H10)2]â\u80\u93, were synthesized through the reactions of CoCl2with [10-MeS-7,8-C2B9H11]â\u80\u93and [9-MeS-7,8-C2B9H11]â\u80\u93in strong alkaline aqueous media. The 4,4â\u80²-(rac) and 4,7â\u80²-(meso) isomers were separated by column chromatography as the tetrabutylammonium salts. The structures of [Bu4N][8,8â\u80²-(MeS)2-3,3â\u80²-Co(1,2-C2B9H10)2], [Bu4N][4,4â\u80²-(MeS)2-3,3â\u80²-Co(1,2-C2B9H10)2], and [Bu4N][4,7â\u80²-(MeS)2-3,3â\u80²-Co(1,2-C2B9H10)2] were determined through single-crystal X-ray diffraction. In the solid state, the rotation of the two dicarbollide ligands with respect to each other is hampered by the formation of intramolecular CH···S(Me) hydrogen bonds between the ligands, and this results in the stabilization of definite rotamers, namely, the transoid conformation for the 8,8â\u80² isomer and the gauche conformations for the 4,4â\u80² and 4,7â\u80² isomers. These data are in a good agreement with the results of quantum-chemical calculations

Nonlinear optical properties of chalcogenopyrylium- terminated heptamethine dyes in multiple polymer hosts

Z-scan and linear loss measurements on polymethine-polymer blends with varied chalcogens and hosts confirm polymethine aggregation as the primary interaction influencing solidstate NLO properties for ultrafast all-optical signal-processing. © OSA 2017

Linear and Third-Order Nonlinear Optical Properties of Chalcogenopyrylium-Terminated Heptamethine Dyes with Rigid, Bulky Substituents

The aggregation of chalcogenopyrylium-terminated heptamethine dyes in high-chromophore density films can be substantially suppressed by attachment of rigid, bulky substituents that project out of the plane of the conjugated π-system of the dye, allowing the retention in the solid state of favorable linear and nonlinear optical properties relevant to all-optical signal processing (AOSP). Dye structures are systematically engineered with a range of out-of-plane substituents to investigate the impacts on the optical properties at 1550 nm in the solid state. Large magnitudes of the third-order susceptibility are obtained for solid films. Very high values of the two-photon figure-of-merit (2PA-FOM), an important parameter for AOSP, are observed in dilute solutions of seleno- and telluropyrylium dyes (in several cases >30). In the case of the telluropyrylium dye, the 2PA-FOM is not measureable for 50 wt% blends with polymers. Blends of the selenopyrylium examples exhibit 2PA-FOM values that, although decreased substantially relative to the solution values, in some cases meet the requirements for AOSP. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei