Optical and H NMR techniques have been applied to the study of a few metal complexes (Co, Fe, and Yb) of the antitumor antibiotic streptonigrin (SN) produced by Streptomyces flocculus to elucidate the structure of the complexes. The hyperfine-shifted H NMR signals of these paramagnetic complexes were fully assigned by means of relaxation and two-dimensional NMR techniques. These studies reveale...

The ladder-like structure of the tetranuclear title compound, [Sn(4)(C(6)H(5))(4)Cl(2)O(2)(OH)(2)(C(9)H(13)N)(2)(C(9)H(12)N)(2)]Cl(2)·10CDCl(3), consists of two five- and two six-coordinated Sn(IV) atoms bridged by oxide or hydroxide groups. The chelating ligands reveal rather strong Sn-N bonds [2.517 (4) Å], but the protonated dimethylamino groups in the periphery of the complex show no intera...

The asymmetric unit of the title complex, [Sn(CH(3))(C(6)H(5))(C(10)H(8)NO)Cl], consists of two independent mol-ecules, both of which have the N,O-chelated Sn(IV) atom in a cis-C(2)SnNOCl trigonal-bipyramidal geometry [C-Sn-C = 124.82 (8) and 137.69 (8)°]. The Cl atom of the mol-ecule with the smaller C-Sn-C angle inter-acts weakly with the Sn(IV) atom of the mol-ecule with the wider C-Sn-C ang...

The new potential tracer of bone imaging, AHBDP-Sn(II)-TcO.3H(2)O was synthesized by reducing the TcO(4) (-) to TcO(2) (+) in the presence of AHBDP and Sn(ll)'s reducing agent. We found that tin rapidly forms a stable complex with AHBDP, giving AHBDP-Sn(II).3H(2)O. In the excess of AHBDP-Sn(ll).3H(2)O, the AHBDP-Sn(II).3H(2)O coordinates with TcO(2) (+) to give AHBDP-Sn(II)-TcO.3H(2)O which cou...

The title tetra-nuclear Sn(IV) complex, [Sn(4)(C(4)H(9))(8)(C(10)H(6)NO(2))(4)O(2)], is a cluster built up by inversion symmetry around the central Sn(2)O(2) ring. The coordination geometries of the Sn atoms involved can be classified into two types: the five-coordinate Sn atoms of the central Sn(2)O(2) core have a trigonal-bipyramidal geometry, with axial positions occupied by a μ(3)-O atom an...