Exploring the Coordination of Plutonium and Mixed Plutonyl-Uranyl Complexes of Imidodiphosphinates.

The coordination chemistry of plutonium(IV) and plutonium(VI) with the complexing agents tetraphenyl and tetra-isopropyl imidodiphosphinate (TPIP- and TIPIP-) is reported. Treatment of sodium tetraphenylimidodiphosphinate (NaTPIP) and its related counterpart with peripheral isopropyl groups (NaTIPIP) with [NBu4]2[PuIV(NO3)6] yields the respective PuIV complexes [Pu(TPIP)3(NO3)] and [Pu(TIPIP)2(NO3)2] + [PuIV(TIPIP)3(NO3)]. Similarly, the reactions of NaTPIP and NaTIPIP with a Pu(VI) nitrate solution lead to the formation of [PuO2(HTIPIP)2(H2O)][NO3]2, which incorporates a protonated bidentate TIPIP- ligand, and [PuO2(TPIP)(HTPIP)(NO3)], where the protonated HTPIP ligand is bound in a monodentate fashion. Finally, a mixed U(VI)/Pu(VI) compound, [(UO2/PuO2)(TPIP)(HTPIP)(NO3)], is reported. All these actinyl complexes remain in the +VI oxidation state in solution over several weeks. The resultant complexes have been characterized using a combination of X-ray structural studies, NMR, optical, vibrational spectroscopies, and electrospray ionization mass spectrometry. The influence of the R-group (R = phenyl or iPr) on the nature of the complex is discussed with the help of DFT studies.

Insights into the structural patterns of the antileishmanial activity of bi- and tricyclic N-heterocycles.

The influence of various structural patterns in a series of novel bi- and tricyclic N-heterocycles on the activity against Leishmania major and Leishmania panamensis has been studied and compounds that are active in the low micromolar region have been identified. Both quinolines and tetrahydrooxazinoindoles (TOI) proved to have significant antileishmanial activities, while substituted indoles were inactive. We have also showed that a chloroquine analogue induces Leishmania killing by modulating macrophage activation.

Unexpected reactivity and coordination in gallium(III) and indium(III) chloride complexes with geometrically constrained thio- and selenoether ligands.

Reaction of GaCl(3) with 1 mol equiv of [14]aneS(4) in anhydrous CH(2)Cl(2) gives the exocyclic chain polymer [GaCl(3)([14]aneS(4))] (1) whose structure confirms trigonal bipyramidal coordination at Ga with a planar GaCl(3) unit. In contrast, using [16]aneS(4) and GaCl(3) or [16]aneSe(4) and MCl(3) (M = Ga or In) in either a 1:1 or a 1:2 molar ratio produces the anion-cation complexes [GaCl(2)([16]aneS(4))][GaCl(4)] (2) and [MCl(2)([16]aneSe(4))][MCl(4)] (M = Ga, 3 and M = In, 4) containing trans-octahedral cations with endocyclic macrocycle coordination. The ligand-bridged dimer [(GaCl(3))(2){o-C(6)H(4)(SMe)(2)}] (5) is formed from a 2:1 mol ratio of the constituents and contains distorted tetrahedral Ga(III). This complex is unusually reactive toward CH(2)Cl(2), which is activated toward nucleophilic attack by polarization with GaCl(3), producing the bis-sulfonium species [o-C(6)H(4)(SMeCH(2)Cl)(2)][GaCl(4)](2) (6), confirmed from a crystal structure. In contrast, the xylyl-based dithioether gives the stable [(GaCl(3))(2){o-C(6)H(4)(CH(2)SEt)(2)}] (8). However, replacing GaCl(3) with InCl(3) with o-C(6)H(4)(CH(2)SEt)(2) preferentially forms the 4:3 In:L complex [(InCl(3))(4){o-C(6)H(4)(CH(2)SEt)(2)}(3)] (9) containing discrete tetranuclear moieties in which the central In atom is octahedrally coordinated to six bridging Cl's, while the three In atoms on the edges have two bridging Cl's, two terminal Cl's, and two mutually trans S-donor atoms from different dithioether ligands. GaCl(3) also reacts with the cyclic bidentate [8]aneSe(2) to form a colorless, extremely air-sensitive adduct formulated as [(GaCl(3))(2)([8]aneSe(2))] (10), while InCl(3) gives [InCl(3)([8]aneSe(2))] (14). Very surprisingly, 10 reacts rapidly with O(2) gas to give initially the red [{[8]aneSe(2)}(2)][GaCl(4)](2) (11) and subsequently the yellow [{[8]aneSe(2)}Cl][GaCl(4)] (12). The crystal structure of the former confirms a dimeric [{[8]aneSe(2)}(2)](2+) dication, derived from coupling of two mono-oxidized {[8]aneE(2)}(+•) cation radicals to form an Se-Se bond linking the rings and weaker transannular 1,5-Se···Se interactions across both rings. The latter (yellow) product corresponds to discrete doubly oxidized {[8]aneSe(2)}(2+) cations (with a primary Se-Se bond across the 1,5-positions of the ring) with a Cl(-) bonded to one Se. Tetrahedral [GaCl(4)](-) anions provide charge balance in each case. These oxidation reactions are clearly promoted by the Ga(III) since [8]aneSe(2) itself does not oxidize in air. The new complexes have been characterized in the solid state by IR and Raman spectroscopy, microanalysis, and X-ray crystallography where possible. Where solubility permits, the solution characteristics have been probed by (1)H, (77)Se{(1)H}, and (71)Ga NMR spectroscopic studies.

Gender, BMI and side-to-side differences in spinal accessory nerve conduction from the upper and middle components of the trapezius muscle.

INTRODUCTION: There is a variety of testing methods described in the literature for the spinal accessory nerve (SAN). This study aims to evaluate side-to-side, gender, and BMI differences with surface recording from the upper and middle trapezius using a standard distance to the upper trapezius. METHODS: Subjects underwent bilateral SAN conduction testing with the active recording electrodes over the superior border of the upper trapezius, midway between the acromion and the C7 spinous process, and over the middle trapezius 3 cm medial to the vertebral border of the scapula. RESULTS: Mean latency values were 2.17 ± 0.22 msec and 3.14 ± 0.40 msec for the upper and middle trapezius, respectively. Mean amplitude values were 8.02 ± 2.2 mV for the upper trapezius and 3.96 ± 1.77 mV for the middle trapezius. The mean side-to-side latency difference was 7.8% for the upper and 9.5% for the middle trapezius, while the mean side-to-side amplitude difference was 18.2% for the upper and 37.6% for the middle trapezius. BMI had a significant inverse effect on upper and middle trapezius amplitudes such that both males and females with lower BMI had larger amplitudes. There was a significant gender difference for upper and middle trapezius latency with faster latency values observed in females. CONCLUSIONS: SAN conduction with surface recording from the upper and middle trapezius is well tolerated. Side-to-side differences may be the best way to evaluate both amplitude and latency, so bilateral testing is essential in light of anatomical variation and BMI effects on amplitude.

Predictive genetic profiles for regional lymph node metastasis in primary cutaneous melanoma: a case-matched pilot study.

Melanoma confers an estimated lifetime risk of one in 50 for 2016. Clinicopathologic staging and sentinel lymph node biopsy (SLNB) have been the standard of care for T2 and T3 lesions. Molecular biomarkers identified in the primary lesion suggestive of metastatic potential may offer a more conclusive prognosis of these lesions. Our purpose was to investigate molecular mutations in primary melanoma that were predictive for micrometastasis as defined by a positive sentinel lymph node (SLN) in a case-controlled manner: nine patients with negative SLN and nine with positive SLN. The two cohorts were statistically identical as shown by a t-test for age (P=0.17), race (P=0.18), Breslow depth (P=0.14), Clark level (P=0.33), host response (P=0.17), ulceration (P=0.50), satellite nodules (P=0.17), lymphovascular invasion (P=0.50), and mitotic activity (P=0.09). While no single gene was significantly associated with SLN status, multivariate analysis using classification and regression tree assessment revealed two unique gene profiles that completely represented regional metastases in our cohort as defined by a positive SLN: PIK3CA (+) NRAS (-) and PIK3CA (-) ERBB4 (-) TP53 (+) SMAD4 (-). These profiles were identified in 89% of the patients with positive SLN; none of these profiles were identified in the SLN-negative cohort. We identified two unique gene profiles associated with positive SLN that do not overlap other studies and highlight the genetic complexity that portends the metastatic phenotype in cutaneous melanoma.

Characterization of Three Venom Peptides from the Spitting Spider Scytodes thoracica.

We present the solution-state NMR structures and preliminary functional characterizations of three venom peptides identified from the spitting spider Scytodes thoracica. Despite little sequence identity to other venom peptides, structural characterization reveals that these peptides contain an inhibitor cystine knot motif common to many venom peptides. These are the first structures for any peptide or protein from spiders of the Scytodidae family. Many venom peptides target neuronal ion channels or receptors. However, we have not been able to determine the target of these Scytodes peptides so we can only state with certainty the channels and receptors that they do not target.

Thio-, seleno- and telluro-ether complexes of aluminium(III) halides: synthesis, structures and properties.

The reaction of AlCl3 with Me2E (E = S, Se or Te) or (n)Bu2E (E = Se or Te) in CH2Cl2 under rigorously anhydrous conditions gave the pseudo-tetrahedral complexes [AlCl3(R2E)]. The [AlX3(Me2E)] (X = Br or I, E = S; X = Br, E = Te) were made from toluene solution since attempted syntheses in CH2Cl2 resulted in substantial chloride incorporation. The synthesis of [(AlCl3)2{o-C6H4(CH2SEt)2}], in which the ligand bridges two tetrahedral aluminium centres, and of the six-coordinate trans-[AlX2{MeE(CH2)2EMe}2][AlX4] (X = Cl or Br, E = S, and X = Cl, E = Se) and cis-[AlI2{MeS(CH2)2SMe}2][AlI4] are reported. The tripodal thioether forms [AlCl3{MeC(CH2SMe)3}], which is a chain polymer with κ(2)-coordinated ligand and a tbp arrangement at Al(iii). Chalcogenoether macrocycle complexes [AlCl3([9]aneS3)], [AlCl2([14]aneS4)][AlCl4] and [AlCl2([16]aneSe4)] [AlCl4] are also described. All complexes were characterised by microanalysis, IR and multinuclear NMR ((1)H, (27)Al, (77)Se or (125)Te) spectroscopy as appropriate. In CH2Cl2 solution [AlCl3(Me2S)] with added Me2S forms [AlCl3(Me2S)2], and the [AlX2{MeS(CH2)2SMe}2][AlX4] exist as mixtures of cis and trans isomers which undergo rapid exchange at ambient temperatures. X-Ray crystal structures are reported for [AlCl3(Me2Se], [AlX3(Me2Te)] (X = Cl or Br), trans-[AlCl2{MeE(CH2)2EMe}2][AlCl4] (E = S or Se), cis-[AlI2{MeS(CH2)2SMe}2][AlI4], [AlCl3{MeC(CH2SMe)3}], and for the sulfonium salt [Me2SH][AlCl4]. The aluminium halide chalcogenoether chemistry is compared with the corresponding gallium and indium systems, and the relative Lewis acidities of the metals discussed. Attempts to use [AlCl3((n)Bu2E)] (E = Se or Te) as LPCVD reagents to form aluminium chalcogenide films were unsuccessful.

Hypervalent neutral O-donor ligand complexes of silicon tetrafluoride, comparisons with other group 14 tetrafluorides and a search for soft donor ligand complexes.

The hypervalent adducts of SiF(4), trans-[SiF(4)(R(3)PO)(2)] (R = Me, Et or Ph), cis-[SiF(4){R(2)P(O)CH(2)P(O)R(2)}] (R = Me or Ph), cis-[SiF(4)(pyNO)(2)] and trans-[SiF(4)(DMSO)(2)] have been prepared from SiF(4) and the ligands in anhydrous CH(2)Cl(2), and characterised by microanalysis, IR and VT multinuclear ((1)H, (19)F, (31)P) NMR spectroscopy. The NMR studies show extensive dissociation at ambient temperatures in non-coordinating solvents, but mixtures of cis and trans isomers of the monodentate ligand complexes were identified at low temperatures. Crystal structures are reported for trans-[SiF(4)(R(3)PO)(2)] (R = Me or Ph), and cis-[SiF(4)(pyNO)(2)]. The GeF(4) analogues cis-[GeF(4){R(2)P(O)(CH(2))(n)P(O)R(2)}] (R = Me or Ph, n = 1; R = Ph, n = 2) were similarly characterised and the structures of cis-[GeF(4){R(2)P(O)CH(2)P(O)R(2)}] (R = Me or Ph) determined. The reaction of R(3)AsO (R = Me or Ph) with SiF(4) does not give simple adducts, but forms [R(3)AsOH](+) cations as fluorosilicate salts. SiF(4) adducts of some ether ligands (including THF, 12-crown-4) were also characterised by (19)F NMR spectroscopy in solution at low temperatures (∼190 K), but are fully dissociated at room temperature. Attempts to isolate, or even to identify, SiF(4) adducts with phosphine or thioether ligands in solution at 190 K were unsuccessful, contrasting with the recent isolation and detailed characterisation of GeF(4) analogues. The chemistry of SiF(4) with these oxygen donor ligands, and with soft donors (P, As, S or Se), is compared and contrasted with those of GeF(4), SnF(4) and SiCl(4). The key energy factors determining stability of these complexes are discussed.