Acetate as a model for aspartate-based CXCR4 chemokine receptor binding of cobalt and nickel complexes of cross-bridged tetraazamacrocycles

Abstract

Ni and Co complexes of cross-bridged vs. unbridged tetraazamacrocycle acetate complexes reveal preferences likely to impact CXCR4 antagonist interactions.

An ethylene cross-bridged pentaazamacrocycle and its Cu2+complex: constrained ligand topology and excellent kinetic stability

“…Numerous studies 5,6 have demonstrated that the first-row transition metal complexes of these ethylene cross-bridged tetraazamacrocycles are among the most kinetically stable towards harsh acidic/basic conditions of known synthetic transition metal complexes. Yet, their tetradentate nature ensures labile coordination sites that allow reactivity and/or binding ability that has made these complexes favoured for catalytic, [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21] biomedical imaging, [22][23][24][25][26][27][28][29][30] and inorganic drug compound [31][32][33][34][35] applications.…”

A Bridge too Far? Comparison of Transition Metal Complexes of Dibenzyltetraazamacrocycles with and without Ethylene Cross-Bridges: X-ray Crystal Structures, Kinetic Stability, and Electronic Properties

“…Cross-bridged tetraazamacrocycles that have an additional two-carbon bridge between non-adjacent nitrogen atoms of a tetraazamacrocycle, which are particularly rigid and lead to very kinetically stable metal complexes, have been extensively studied by Weisman [ 1 , 2 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 ], Springborg [ 13 , 14 , 15 ], Hubin [ 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 ], Archibald [ 24 , 25 , 26 , 27 , 28 , 29 , 30 ], Tripier [ 31 , 32 , 33 , 34 , 35 , 36 ], and others [ 37 , 38 , 39 ]. This stability conferred on these transition metal complexes shows great promise in such applications as homogeneous catalysis [ 40 , 41 , 42 , 43 ], inorganic drug candidates [ 20 , 24 , 26 , 27 , 44 , 45 , 46 ], and biomedical imaging agents [ ...…”

Expanding and quantifying the crystal chemistry of the flexible ligand 15aneN5

“…1 above. 8–12 These are desirable traits for restricting the complex coordination geometry 13–18 and for applications where the kinetic stability of the complex is desirable, such as in biological or medical uses, 19–29 or in catalytic reactions under harsh conditions. 30–42 Recently, we have decided to investigate ethylene cross-bridged analogues of the larger pentaazamacrocycles, hoping to produce similarly useful, kinetically stable coordination complexes.…”