Active Cytotoxic Reagents Based on Non-metallocene Non-diketonato Well-Defined <i>C</i><sub>2</sub>-Symmetrical Titanium Complexes of Tetradentate Bis(phenolato) Ligands
作者:Michal Shavit、Dani Peri、Cesar M. Manna、Jacob S. Alexander、Edit Y. Tshuva
DOI:10.1021/ja0753086
日期:2007.10.1
of non-Cp-based non-diketonato-based C2-symmetrical octahedral Ti(IV) complexes of dianionic diaminebis(phenolato) ligands, which are conveniently obtained as single isomers in quantitative yields, leads to appreciable cytotoxicity against colon and ovarian cells with a non-transferrin-dependent cell penetration mechanism. The ligand structural features including steric demands, symmetry, and aromaticity
Single-step synthesis of salans and substituted salans by Mannich condensation
作者:Edit Y Tshuva、Natalie Gendeziuk、Moshe Kol
DOI:10.1016/s0040-4039(01)01264-3
日期:2001.9
A convenient route for the synthesis of a variety of salan-type compounds is introduced. The synthesis is based on a single-step Mannichcondensation between readily available starting materials: primary or secondary amines, formaldehyde and substituted phenols. This methodology is suitable for the preparation of chiral salans as well, which may find applications in asymmetric catalysis.
Four linear trinuclear manganese complexes containing ligands with an N2O2 donor set have been prepared and characterized structurally and magnetically. The complexes have the general formula [Mn-3(L-n)(2)(OAc)(2)(OCH3)(2)] (n = 1, 2, 3, 4. H2L1 = N,N'-dimethyl-N,N'-(2-hydroxy-4,5-dimethylbenzyl)ethylenediamine, H2L2 = N,N-bis(3,4-dimethyl-2-hydroxybenzyl)-N-(2-pyridylmethyl)amine, H2L3 = N,N-bis(3,4-dimethyl-2-hydroxybenzyl)-N,N'-dimethylethylenediamine, H2L4 = N,N-bis(3,4-dimethyl-2-hydroxybenzyl)-2-amino-ethanol). X-ray single-crystal structure analyzes of the complexes show that the linear Mn-III-Mn-II-Mn-III cores are triply bridged by phenolate. acetate (syn-syn), and MeO- groups with the Mn-III and Mn-II distances in the range 3.123(3)-3.167(4)angstrom. Magnetic studies show that the spin exchange coupling constants (J) between Mn-III and Mn-II ions range from -1.58(1) to 1.15(3) cm(-1) ((H) over cap = -2J((S) over cap (1) center dot (S) over cap (2) + (S) over cap (1) center dot (S) over cap (3))). The antiferromagnetic and ferromagnetic interactions were analyzed based on the structural features, and the Mn-III-O-Mn-II bond angles have been found to be the dominant factor affecting the intermetallic magnetic coupling. (C) 2012 Elsevier Ltd. All rights reserved.
ACTIVE NON-METALLOCENE PRE-CATALYST AND METHOD FOR TACTIC CATALYTIC POLYMERIZATION OF ALPHA-OLEFIN MONOMERS