New organometallic complexes [M(dppe)(R)] {where M = Pt or Pd, dppe = 1,2-bis(diphenylphosphano)ethane, and R = CFH-x (x = 6,5,4), CFH-3,5, CFH-5,6, CFH-3,6, CF(OMe)-4, and CF(cyclo-CHN)-4, the numbers x refer to the positions of the protons in the polyfluoroaryl ligands} were synthesised either through transmetalation from the dichlorido complexes [M(dppe)Cl] or through ligand exchange using [M(diene)Cl] precursor complexes with diene = 1,5-cyclooctadiene (cod) or 1,5-hexadiene (hex). Alternatively, [M(dppX)Cl(R)] complexes with dppX = dppm (1,1-bis(diphenylphosphano)methane), dppe, dppp (1,3-bis(diphenylphosphano)propane), and dppb (1,4-bis(diphenylphosphano)butane) were prepared in decarboxylation reactions from thallium(i) carboxylates Tl(OCR). The different preparative methods were compared in terms of yield and purity. Structural and spectroscopic data are reported for the new dppX- and diene-M(R) complexes. Antiproliferative activity was investigated for these new complexes against the HT-29 (colon carcinoma) and MCF-7 (breast adenocarcinoma) cell lines, and the active compounds of this first series together with organometallic dppX or hex Pt or Pd complexes were then included in cell tests using L1210 (leukaemia cells) and the cisplatin-resistant L1210/DDP cell line. Remarkably, promising antiproliferative results were found for a few Pt and Pd complexes, while structurally closely related compounds were essentially nontoxic.
The polyfluorophenylsilver complexes [Ag2(C6F4Br‐4)2(py)3] (py = pyridine) (1) and [{Ag2R2(py)2}n] [R = C6F5 (2); C6F4Br‐3 (3); C6F4H‐4 (4)] were prepared in reasonable yields by reactions of silver(I) oxide with the appropriate polyfluorobenzenes in pyridine. This simple and convenient synthesis is selective and does not lead to debromination of C6HF4Br‐(3 or 4). Complex 1 is dinuclear with AgR2 and Ag(py)3 units linked by a bridging polyfluoroaryl group and Ag···Ag interactions, whereas 2–4 are polymeric with alternating AgR2 and Ag(py)2 units similarly linked. The trivalent lanthanoid pyrazolates, [Ln(Ph2pz)3(py)2]·2thf (Ph2pz = 3,5‐diphenylpyrazolate; Ln = Yb, 5, Er, 6, Dy, 7, Lu, 8; thf = tetrahydrofuran), [Ho(Ph2pz)3(py)(thf)] (9), [Ln(Ph2pz)3(py)(dme)]·solv (Ln = Tb, solv = 1.75PhMe, 10, Gd, solv = 1.5dme, 11; dme = 1,2‐dimethoxyethane; PhMe = toluene), [Ln(Ph2pz)3(thf)3] (Ln = La, 12, Ce, 13, Nd, 14), [Ln(tBu2pz)3(py)2] (tBu2pz = 3,5‐di‐tert‐butylpyrazolate; Ln = Yb, 15, Tm, 16, Ho, 17, Dy, 18), [Yb(Phtpz)3(py)2]·PhMe (19) (Phtpz = 3‐Phenyl‐5‐(2′‐thienyl)pyrazolate) and [Nd(ttfpz)3(dme)2] (20) (ttfpz = 3‐(2′‐thienyl)‐5‐(trifluoromethyl)pyrazolate) have been prepared by redox transmetallation/protolysis (RTP) reactions employing lanthanoid metals, pentafluorophenylsilver and the corresponding pyrazoles (pzH) in donor solvents. This is a new synthetic route in which AgC6F5 replaces the more commonly used Hg(C6F5)2 or HgPh2. Yields are good to excellent if long crystallization times are used but the heavier Ln metals require activation with iodine to induce reaction. The monomeric structures exhibit η2‐bound pyrazolate ligands with eight‐coordinate metal atoms for complexes 5–9 and 15–19, nine‐coordinate metal atoms for complexes 10–14, and ten‐coordinate metal atoms for complex 20.
The structures of three adventitiously obtained peroxolanthanoid complexes have been determined, namely, [Yb2(Cp)4(μ-O)2/3(μ-O2)1/3(thf)2] (1) (Cp = cyclopentadienyl; thf = tetrahydrofuran), which has disorder between the bridging oxide and peroxide, [Nd2(o-PhPhForm)4(thf)4(μ-O2)] (2) (o-PhPhForm = N,N′-bis(2-phenylphenyl)formamidinate), and [Eu4(FForm)6(μ-OH)2(μ3-O2)2(μ-diglyme)2]·2diglyme (3) (FForm = N,N′-bis(2-fluorophenyl)formamidinate, diglyme = bis(2-methoxyethyl) ether). In the first two complexes, the peroxide bridges side-on between metals, whereas in the last complex, each peroxide bridges three metals through both oxygen atoms. The first complex was a single crystal amongst a bulk sample of [Yb(Cp)2(pzPh)(thf)] (pzPh = 2-(1′-pyrazolyl)phenyl), prepared by oxidation of dicyclopentadienylytterbium(ii) by bis(2-(1′-pyrazolyl)phenyl)mercury, the structure of which was also determined and showed distorted square planar stereochemistry for mercury.
Introduction: Previous research suggests children diagnosed with autism spectrum disorder (ASD or “autism”) born extremely and very preterm face substantially delayed development than their peers born full-term. Further, children born preterm are proposed to show a unique behavioral phenotype, which may overlap with characteristics of autism, making it difficult to disentangle their clinical presentation. To clarify the presentation of autism in children born preterm, this study examined differences in key indicators of child development (expressive language, receptive language, fine motor, and visual reception) and characteristics of autism (social affect and repetitive, restricted behaviors).Materials and Methods: One fifty-eight children (136 full-term, twenty-two preterm) diagnosed with autism, aged 22–34 months, were identified prospectively using the Social Attention and Communication Surveillance tools during community-based, developmental surveillance checks in the second year of life. Those identified at “high likelihood” of an autism diagnosis were administered the Mullen Scales of Early Learning and the Autism Diagnostic Observation Schedule.Results: The children born preterm and full-term did not differ significantly in their fine motor, visual reception, expressive language, or receptive language skills. No significant differences in social affect and repetitive and restrictive behavior traits were found.Discussion: The findings of this study differs from previous research where children diagnosed with autism born very or extremely preterm were developmentally delayed and had greater autistic traits than their term-born peers. These null findings may relate to the large proportion of children born moderate to late preterm in this sample. This study was unique in its use of a community-based, prospectively identified sample of children diagnosed with autism at an early age. It may be that children in these groups differ from clinic- and hospital-based samples, that potential differences emerge later in development, or that within the autism spectrum, children born preterm and full-term develop similarly. It was concluded that within the current sample, at 2 years of age, children diagnosed with autism born preterm are similar to their peers born full-term. Thus, when clinicians identify characteristics of autism in children born preterm, it is important to refer the child for a diagnostic assessment for autism.
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