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The second-generation xanthate ligand 4-PyCH 2 OCS 2 Na, consisting of a backbone functionalized O -alkyldithiocarbonate donor set, has been prepared. The reaction of this ligand with either Ph 3 SnCl or (Ph 3 P) 2 CuNO 3 yields the neutral monometallic complexes [4-PyCH 2 OCS 2 SnPh 3 ] and [4-PyCH 2 OCS 2 Cu(PPh 3 ) 2 ], respectively. These compounds were characterized by 1 H NMR and UV–Vis spectroscopies, and in solid state by single crystal X-ray diffraction. The structure of [4-PyCH 2 OCS 2 SnPh 3 ] consists of a mono-dimensional coordination polymer, formed by the monodentate coordination of the O CS 2 − group to the Sn(IV) center, in combination with the coordination of the pyridine group to an adjacent tin atom. In the case of [4-PyCH 2 OCS 2 Cu(PPh 3 ) 2 ], the xanthate ligand coordinates to the Cu(I) center in an isobidentate fashion, leaving the pyridine moiety free. These monometallic complexes act as metalloligands toward the [Rh 2 (OAc) 4 ] dimer, producing the tetrametallic derivatives [Rh 2 (OAc) 4 ]·2[4-PyCH 2 OCS 2 SnPh 3 ] and [Rh 2 (OAc) 4 ]·2[4-PyCH 2 OCS 2 Cu(PPh 3 ) 2 ], respectively. These compounds were investigated in solution phase using 1 H NMR and UV–Vis techniques, and it is proposed that the formation of the first compound proceeds via a two-step process, while the formation of the latter is a one-step process. [ABSTRACT FROM AUTHOR]

Highlights: [•] Ditopic dithiophosphonate ligands have been prepared. [•] Sn(IV) and Cu(I) complexes have been synthesized and characterized. [•] X-ray diffractions studies were performed. [•] π–π and CH⋯π interactions support supramolecular structures of these complexes. [Copyright &y& Elsevier]

Abstract: Nowadays, investigation for possible therapeutic applications of various metal-based drugs attracts the scientific interest worldwide. The triorganotin compound bis[triphenyltin(IV)](3-carboxy-pyridine-2-thionato) (SnMNA), was tested for its anti-proliferative and antitumor activities. Cytotoxic activity was assessed by Trypan blue and 3-(4.5-dimethylthiazol-2-yl)-2.5-diphenyltetrazolium bromide assay (MTT). SnMNA exhibited potent cytotoxic effects against leiomyosarcoma cells (LMS) and human breast adenocarcinoma cells (MCF-7), which is 200 times stronger than that of cisplatin. Moreover, SnMNA induced significant apoptosis in LMS and MCF-7 cells characterized by flow cytometry analysis and DNA fragmentation. Acute and chronic toxicity studies on Wistar rats caused kidney and lung toxicity at a single dose of 80mg/kgBody Weight (BW) or four repeated doses of 8mg/kgBW once per week. Furthermore, antitumor activity studies on sarcoma bearing Wistar rats revealed that SnMNA complex at four repeated doses of 5.4mg/kgBW every three days prolonged mean survival time of the animal at 200% and decreased mean tumor growth rate (MTGR) compared to the control group (p <0.05). It is noteworthy to mention that the 30% (3 out of 10) of the bearing animals were totally cured. These findings indicate that SnMNA might be a promising new antitumor agent. [ABSTRACT FROM AUTHOR]

Abstract: Heavy group 13 and 14 analogs of the poly(pyrazolyl)borates are the subject of this review. Within these, the most extensive research has been performed on the study of polypyrazolylgallates Me2Ga(R2pz)2]− (R=H or Me) and [MeGa(pz)3]−, and their complexes with transition metals. In this review, the common features shared with the boron analogs are presented and contrasted. Other recently reported series of group 13 analogs are the alkali polypyrazolylaluminates Na[(R2pz)3 ] with R=Me, t Bu; R′=M. The complexes with one or two pyrazolyl ligands on aluminum display anagostic Al–CH3⋯Na interactions, these interactions are persistent even if complexes were obtained from solutions with THF that normally coordinate alkali ions. The polypyrazolylsilane ligands Me2Si(R2pz)2 and MeSi(R2pz)3 with R=H, Me are remarkably easy to obtain and isolate, in contrast is the fact that the carbon analogs are much harder to obtain and isolate in reasonable yields. Therefore it is surprising that the chemistry of the former ligands is not as developed as could be anticipated. Nevertheless there are examples of the use of these silanes as ligands with the following transition metals: Cr, Mn, Cu, Zn, Sc and Zr. The heavier group 14 analogs with Ge and Sn display coordination patterns with alkali and alkaline ions that resemble those observed with the borates and aluminates. The formation of cationic bimetallic cages of the type [E2(R2pz)3]+ and neutral complexes [E2(R2pz)4] has also been observed that can be consider formal isomers of the alkenes. The use of these compounds as ligands has been recently reported. [Copyright &y& Elsevier]

Abstract: The organometallic tin(IV) complexes [SnPh2(SRF)2] SRF = −SC6F4-4-H (1), −SC6F5 (2), were synthesized and their reactivity with [MCl2(PPh3)2] M=Ni, Pd and Pt explored. Thus, transmetallation products were obtained affording polymeric [Ni(SRF)(μ-SRF)] n , monomeric cis-[Pt(PPh3)2(SC6F4-4-H)2] (3) and cis-[Pt(PPh3)2(SC6F5)2] (4) and dimeric species [Pd(PPh3)(SC6F4-4-H)(μ-SC6F4-4-H)]2 (5) and [Pd(PPh3)(SC6F5)(μ-SC6F5)]2 (6) for Ni, Pt and Pd, respectively. The crystal structures of complexes 1, 2, 3, 4 and 6 were determined. [Copyright &y& Elsevier]

Abstract: Treatment of dibenzyltin dichloride with 1 equiv. of 2-amino-1-cyclopentene-1-carbodithioic acid (ACDA) gave Bz2SnCl(ACDA) (1) that contains five coordinate tin. Reaction of 2 equiv. of ammonium 2-amino-1-cyclopentene-1-carbodithioic acid (AACD) with Bz2SnCl2 and then recrystallization from THF produced Bz2Sn(ACDA)2 ·THF 2 in which the coordination geometry around the Sn is highly distorted from octahedral. Bz3Sn(ACDA) (3) was obtained from reaction of Bz3SnCl with 1 equiv. of AACD. The crystal structure of 3 indicates a Sn–S′ interaction [3.0823(5)Å] that distorts the tin coordination geometry from that of an ideal tetrahedron. In 1–3 the tin atom is also coordinated to one carbon atom of each benzyl group. The products were characterized by IR and NMR (1H, 13C, 119Sn) spectroscopy and elemental analysis. [Copyright &y& Elsevier]

The electronic structure of newly synthesized tin anticancer complexes coordinating one, two and four tin atoms has been studied both at semiempirical level and by using ab initio methods at the correlation level. The most probable structures of the systems under consideration have been determined being in a good agreement with the relevant experimental results. The compounds show very effective antitumor cytotoxic activity against A549 and HSMC cells. [Copyright &y& Elsevier]

The dithiocarboxylato complexes of tin, Bz2SnCl(EtACDA) (1a) Bz=benzyl, Bz2Sn(EtACDA)2 (1b), and Bz3Sn(EtACDA) (1c) have been synthesized by the reaction of Bz2SnCl2 or Bz3SnCl with 2-N-ethylamino-1-cyclopentene-1-carbodithioic acid (HEtACDA). The reaction of 2-amino-1-cyclopente-1-carbodithioic acid (H2ACDA) with benzylamine, gave 2-N-benzylamino-1-cyclopente-1-carbodithioic acid (HBzACDA) (2), which reacts with Bz2SnCl2 or Bz3SnCl to give Bz2SnCl(BzACDA) (3a), Bz2Sn(BzACDA)2 (3b) and Bz3Sn(BzACDA) (3c). The products were characterized by IR and NMR (1H, 13C and 119Sn) spectroscopies and elemental analysis. The crystal structures of 1c, 2 and 3b have also been determined. In all the complexes Sn is bound asymmetrically to the dithiocarboxylato ligand through two sulfur atoms. The orientation of the ligands is determined by NH⋯S hydrogen bonds. [Copyright &y& Elsevier]