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Abstract: Titanocene dichloride and budotitane have opened a new chapter in medicinal chemistry of titanium(IV) complexes being novel non-platinum antitumor metallic agents. Numerous efforts have led to the discovery of the diamino bis-phenolato titanium(IV) complexes. Among which, the [ONNO] and [ONON] type ligands namely Salan, Salen and Salalen coordinated titanium(IV) alkoxyl complexes have demonstrated significantly enhanced aqueous stability, their in vitro and in vivo antitumor efficacy, mechanism of action, structure-activity relationships and combined tumor therapy have been intensively investigated. Replacement of the labile alkoxyls with a second chelator resulted in structural rigid titanium(IV) complexes, which showed exceedingly good aqueous stability and potent antitumor activity both in vitro and in vivo. The unique ligand system successfully allowed the access of isotopic [45Ti]Titanium(IV) complexes, post-synthetic modification, facile synthetic protocols and antitumor congeneric zirconium(IV) and hafnium(IV) complexes. This review presents recent research progress in the field of antitumor group 4 metal complexes stabilized with phenolato ligands; especially their structure-activity relationships are summarized.

Sleep debt (SD) is one of the important triggers for causing not only physiological and mental illness but also dangerous work. Therefore, achieving an early and objective assessment of SD is of great significance in the precaution against SD-related diseases and unsafe work. Here, an ultrasensitive electrochemical immunosensor was constructed for analysis of SD biomarker amyloid-β (Aβ). The gold nanoparticles/chitosan-coated polyaniline-functionalized activated carbon (AuNPs/AC@PANI@CS) composites were employed as the sensing platforms. Since PANI and AC can form an effective conductive path, it can effectively enhance the penetration of electrolytes on the electrode surface and the rapid transport of charges and ions, significantly enhancing the electrochemical response signal of the immunosensor. Under the optimized experimental conditions, the fabricated immunosensor had a wide linear range of 1.95 pg mL

Four novel Salan Hf

Novel anti-tumoral diamino-bis-(phenolato) [ONON] type titanium

C27H25N3O10Ti, monoclinic, P21/n (no. 14), a = 11.3366(11) Å, b = 11.0253(11) Å, c = 23.7160(2) Å, β = 100.839(2)°, V = 2911.4(5) Å3, Z = 4, R gt (F) = 0.0615, wR ref (F 2) = 0.1411, T = 296(2) K.

C33H29N3O6Ti, monoclinic, C2/c (no. 15), a = 27.4022(15) Å, b = 14.0345(7) Å, c = 17.0047(10) Å, β = 116.009(3)°, V = 5877.3(6) Å3, Z = 8, R gt (F) = 0.0369, wRref (F 2) = 0.1125, T = 100(2) K.

One trimetallic compound (μ-η2-Ni-1)[W(CO)5]2 (NiW2) was prepared by reaction of the Ni(II) dithiolate metalloligand, [Ni-bme-dach] where bme-dach = bis-(mercaptoethyl)diazacycloheptane, with W(CO)6 in CH2Cl2 under a certain treatment. Two solvent-free polymorphs of NiW2 (I and II) and two solvates NiW2(CH2Cl2) (III) and NiW2(C6H6) (IV) were obtained by crystallization in various solvent conditions. Conformations I and II exhibit concomitant polymorphisms in CH2Cl2 solvent system. However, conformations of III and IV were obtained in mixed solvent system of CH2Cl2 with CHCl3 and benzene, respectively. For morph II*, it was obtained by heating treatment of conformation II at 160 °C for 20 min. Two low-valent metallic W0(CO)5 groups in I to IV were bridged by Ni-1 in the transoid modes, giving W-W distances of 5.576(17) A to 6.024(3) A.

Four novel bidentate phosphine-Pd complexes coordinated by NiN2S2 metallodithiolate ligands were synthesized and characterized, including XRD analysis; these redox-active complexes are stable in air, and they survive column chromatography on silica gel. The Ni–Pd bimetallic complexes are demonstrated to be precatalyst for Suzuki–Miyaura cross-coupling reactions. The best of these has an overall yield of over 99% under only 1% catalyst loading. The role of NiN2S2 as a stabilizing bidentate ligand that is also oxidizable may account for its efficacy in the support of the catalysis.

Herein we report the synthesis and structural characterization of a series of novel Zr(IV)salan complexes. The initial metalation product [(L1)2Zr] is highly water sensitive while ligand exchanged [L1Zr(dipic)] hydrolyses slowly with a bis-hydroxo Zr(IV) species identified by MS as an intermediate. [L1Zr(dipic)] is cytotoxic in the range of cisplatin against two human carcinoma cell lines. published

A series of novel sulfonamide substituted heteroleptic salan titanium(IV)-bis-chelates complexed to 2,6-pyridinedicarboxylic acid were synthesized, structurally characterized and evaluated for their anticancer activity against two human carcinoma cell lines. All cytotoxic complexes showed complete inhibition of cell growth at active concentration, two complexes based on pyrrolidine and azepane substituted sulfonamides displayed IC50 values below 1.7 μM and are more cytotoxic than cisplatin in both tested cell lines. The azepane substituted complex [L3Ti(dipic)] exhibited excellent activity with an IC50 value of 0.5 ± 0.1 μM in Hela S3 and 1.0 ± 0.1 μM in Hep G2.

An efficient palladium-catalyzed tandem amination approach was developed in one step to afford functionalized 4-quinolones in good to excellent yields from easily accessible o-haloaryl acetylenic ketones and primary amines.

A simple and efficient palladium-catalyzed amidation–hydrolysis reaction has been developed to afford N-aryl monosubstituted carboxamides in good to excellent yields from easily accessible ketone-derived gem-dihaloolefins and aryl amines.

A simple and efficient palladium-catalyzed amidation-hydrolysis reaction has been developed to afford N-aryl monosubstituted carboxamides in good to excellent yields from easily accessible ketone-derived gem-dihaloolefins and aryl amines.