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41.
Sarah Fakih Wing Chau Tung Dirk Eierhoff Christian Mock Bernt Krebs 《无机化学与普通化学杂志》2005,631(8):1397-1402
In modern cancer therapy the clinical application of platinum‐based drugs is more and more limited by the occurrence of intrinsic or acquired resistances. In this context the potential use of dinuclear platinum complexes in chemotherapy is increasingly relevant. The novel complexes Pd(Bzdpa)Cl2, Pd2(C4H8(dpa)2)Cl4, and Pt2(C4H8(dpa)2)Cl4 allow a direct comparison of mono‐ and dinuclear palladium and platinum complexes respectively deriving from a 2,2′‐dipyridylamine (Hdpa) ligand system. They were characterized by single crystal X‐ray analysis as well as infrared spectroscopy and elemental analysis. The cisplatin analogous mononuclear palladium complex Pd(Bzdpa)Cl2 ( 1 ) (Bzdpa: (2,2′‐dipyridylbenzyl)amine) belongs to a range of 2,2′‐dipyridylamine‐based compounds which were extensively studied in our laboratories. 1 crystallizes in the orthorhombic space group Pna21 with a = 13.722(3), b = 13.457(3), c = 9.483(2), V = 1751.1(6) Å3, and Z = 4. The metal binding motif of 1 was expanded by a flexible butyl‐linker to form the tetradentate C4H8(dpa)2 ligand. The resulting isotypic dinuclear complexes Pd2(C4H8(dpa)2)Cl4·2CH3CN ( 2 ) and Pt2(C4H8(dpa)2)Cl4·2CH3CN ( 3 ) crystallize in the triclinic space group with a = 7.8427(2), b = 8.7940(2), c = 11.7645 (3), α = 79.219(2)°, β = 84.033(2)°, γ = 87.744(2)°, V = 792.58(3) Å3 ( 2 ) and a = 7.831(5), b = 8.814(5), c = 11.817(5), α = 79.271(5)°, β = 83.571(5)°, γ = 88.063(5)°, V = 796.3(8) Å3 ( 3 ), both with one centrosymmetrical molecule in the unit cell. 相似文献
42.
Stephan Ktte Lutz Stelzig Ralf Wonnemann Bernt Krebs Alexander Steiner 《无机化学与普通化学杂志》2000,626(7):1575-1582
The reaction of cadmium salts with various amounts of the tridentate NS2‐chelating ligands 1‐(2‐mercapto‐acetophenone)‐4‐triphenylmethylthiosemicarbazone (H2L1) and 1‐(5‐mercapto‐3‐methyl‐1‐phenylpyrazole‐4‐carboxaldehyde)‐4‐triphenyl‐methylthiosemicarbazone (H2L2) in the presence of bases like N‐methylimidazole (N–MeIm), pyridine (py) or triethylamine (Et3N) provided a series of novel mono‐, di‐, tri‐ and heptanuclear cadmium complexes. They are of the general formulas [CdL1(N–MeIm)]2 ( 1 ), [CdL1(py)]2 ( 2 ), [CdL2(N–MeIm)]2 ( 3 ), [CdL2(py)3] · 0.25 C6H14 · 0.5 py ( 4 ), [Et3NH]2[Cd3L ] · 7 MeOH ( 5 ), [Et3NH]2[Cd3L ] ( 6 ) and [Et3NH]2[Cd7L ] · 14 MeOH ( 7 ). The compounds were characterized by elemental analysis, IR‐ and 1H‐NMR‐spectroscopy. Single‐crystal X‐ray structure analyses are reported for the complexes 2 , 4 , 5 and 7 . While 2 has a dimeric structure where each cadmium ion is pentacoordinated in a N2S3‐environment, 4 consists of a monomeric cadmium center with distorted octahedral N4S2‐coordination. The complexes 5 and 7 exhibit new structural types for tri‐ and heptanuclear cadmium compounds. It is shown that sulfur bridging might proceed via arylthiolates, iminothiolates or even both functions of the ligand. Aggregation is influenced by various factors like solvents, counterions and ligand properties. 相似文献
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The purpose of this paper is to present a general stochastic calculus
approach to insider trading. We consider a market driven by a standard Brownian
motion $B(t)$ on a filtered probability space $\displaystyle
(\Omega,\F,\left\{\F\right\}_{t\geq 0},P)$ where the coefficients are
adapted to a filtration ${\Bbb G}=\left\{\G_t\right\}_{0\leq t\leq T}$,
with $\F_t\subset\G_t$ for all $t\in [0,T]$, $T>0$ being a fixed terminal time.
By
an {\it insider} in this market we
mean a person who has access to a filtration (information)
$\displaystyle{\Bbb H}=\left\{\H_t\right\}_{0\leq t\leq T}$ which is strictly
bigger than the filtration
$\displaystyle{\Bbb G}=\left\{\G_t\right\}_{0\leq t\leq T}$.
In this context an insider strategy is represented by an
$\H_t$-adapted process
$\phi(t)$ and we interpret all anticipating integrals as
the forward integral defined in
[23] and [25].
We consider an optimal portfolio problem with
general utility for an insider with access to a general information
$\H_t \supset\G_t$ and show that if
an optimal insider portfolio $\pi^*(t)$ of this problem exists, then
$B(t)$ is an $\H_t$-semimartingale, i.e. the enlargement
of filtration property holds. This is a converse of previously
known results in this field.
Moreover, if $\pi^*$ exists
we obtain an explicit expression in terms of $\pi^*$ for the
semimartingale decomposition of $B(t)$ with respect to $\H_t$.
This is a generalization
of results in [16], [20] and [2]. 相似文献
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