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61.
Christiane Fernandes James L. Wardell Janet M. S. Skakle 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(8):o499-o502
The molecule of 2-(hydroxymethyl)-1,3-propanediol, C4H10O3, lies across a mirror plane in space group P21/m, with disorder of both terminal hydroxyl H atoms. The molecules are linked by three O—H⋯O hydrogen bonds which combine to form sheets; in each O—H⋯O bond, the H atom resonates between the two O atoms. In the crystal structure of N,N′-bis[2-hydroxy-1,1-bis(hydroxymethyl)ethyl]malonamide, C11H22N2O8, the molecule lies about a twofold axis and has four strong hydrogen bonds which form a mixture of chains and dimers; these combine to give a three-dimensional supramolecular framework. 相似文献
62.
Dendritic Glycopolymer as Drug Delivery System for Proteasome Inhibitor Bortezomib in a Calcium Phosphate Bone Cement: First Steps Toward a Local Therapy of Osteolytic Bone Lesions 下载免费PDF全文
63.
Dr. Christiane Lang Sebastian Bestgen Dr. Alexander Welle Rouven Müller Prof. Peter W. Roesky Prof. Christopher Barner‐Kowollik 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(42):14728-14731
A platform technology for the creation of spatially resolved surfaces encoded with a monolayer consisting of different metal complexes was developed. The concept entails the light‐triggered activation of a self‐ assembled monolayer (SAM) of UV‐labile anchors, that is, phenacylsulfides, and the subsequent cycloaddition of selected diene‐functionalized metal complexes at defined areas on the surface. The synthesis and characterization of the metal complexes for the UV‐light assisted anchoring on the surface and a detailed study of a short‐chain oligomer model system in solution confirm the high efficiency of the photoreaction. The hybrid materials obtained by this concept can potentially be utilized for the design of highly valuable catalytic or (opto‐)electronic devices. 相似文献
64.
Marius Durea Radu Strugariu Christiane Tammer 《Journal of Optimization Theory and Applications》2017,175(3):738-763
The aim of this paper is to address new approaches, in separate ways, to necessary and, respectively, sufficient optimality conditions in constrained vector optimization. In this respect, for the necessary optimality conditions that we derive, we use a kind of vectorial penalization technique, while for the sufficient optimality conditions we make use of an appropriate scalarization method. In both cases, the approaches couple a basic technique (of penalization or scalarization, respectively) with several results in variational analysis and optimization obtained by the authors in the last years. These combinations allow us to arrive to optimality conditions which are, in terms of assumptions made, new. 相似文献
65.
66.
Ergot alkaloids are toxins and important pharmaceuticals which are produced biotechnologically on an industrial scale. They have been identi?ed in two orders of fungi and three families of higher plants. The most important producers are fungi of the genera Claviceps, Penicillium and Aspergillus (all belonging to the Ascomycota). Chemically, ergot alkaloids are characterised by the presence of a tetracyclic ergoline ring, and can be divided into three classes according to their structural features, i.e. amide- or peptide-like amide derivatives of D-lysergic acid and the clavine alkaloids. Signi?cant progress has been achieved on the molecular biological and biochemical investigations of ergot alkaloid biosynthesis in the last decade. By gene cloning and genome mining, gene clusters for ergot alkaloid biosynthesis have been identi?ed in at least 8 different ascomycete species. Functions of most structure genes have been assigned to reaction steps in the biosynthesis of ergot alkaloids by gene inactivation experiments or biochemical characterisation of the overproduced proteins. 相似文献
67.
The label-free time-resolved reflectometric interference spectroscopy has been used to study the interaction of the human
estrogen receptor alpha (ERa) and different types of ligands. Different possible sensor surface coatings including various
estrogen derivatives were evaluated for their suitability for detection of ERa. The determination of the kinetic and thermodynamic
constants was carried out for the interaction in the heterogeneous phase as well as for the interaction in homogeneous phase.
In addition, the affinity of 11 ligands ranging from natural hormones and pharmaceuticals to endocrine disrupting chemicals
(EDCs) has been determined with this label-free assay format. 相似文献
68.
Christiane Kraus 《Constructive Approximation》2011,33(2):191-217
The aim of this paper is to extend the classical maximal convergence theory of Bernstein and Walsh for holomorphic functions
in the complex plane to real analytic functions in ℝ
N
. In particular, we investigate the polynomial approximation behavior for functions F:L→ℂ, L={(Re z,Im z):z∈K}, of the structure F=g[`(h)]F=g\overline{h}, where g and h are holomorphic in a neighborhood of a compact set K⊂ℂ
N
. To this end the maximal convergence number ρ(S
c
,f) for continuous functions f defined on a compact set S
c
⊂ℂ
N
is connected to a maximal convergence number ρ(S
r
,F) for continuous functions F defined on a compact set S
r
⊂ℝ
N
. We prove that ρ(L,F)=min {ρ(K,h)),ρ(K,g)} for functions F=g[`(h)]F=g\overline{h} if K is either a closed Euclidean ball or a closed polydisc. Furthermore, we show that min {ρ(K,h)),ρ(K,g)}≤ρ(L,F) if K is regular in the sense of pluripotential theory and equality does not hold in general. Our results are based on the theory
of the pluricomplex Green’s function with pole at infinity and Lundin’s formula for Siciak’s extremal function Φ. A properly chosen transformation of Joukowski type plays an important role. 相似文献
69.
70.
Stphane Cordier Kaplan Kirakci Guillaume Pilet Denise Mry Didier Astruc Andr Perrin Christiane Perrin 《Progress in Solid State Chemistry》2005,33(2-4):81-88
The [(M6L12i)L6a]n− and [(M6L8i)L6a] units (a = apical, i = inner) constitute the basic building blocks in the octahedral cluster chemistry. Nano-sized metallic clusters are easily obtained by solid state synthesis with transition elements associated with halogen or chalcogen. The intrinsic properties of M6 cluster units—one or two electron reversible redox process, magnetism and luminescence—depend on the nature of the metal and ligands. The solubilisation of M6 solid state compounds provides [(M6L12i)L6a]n− or [(M6L8i)L6a]n− building blocks with individual properties that can be further used for the design of hybrid organic/inorganic materials. Several examples of solid state precursors are presented as well as substitution reactions of apical ligands in solution. Indeed, hexacyano M6 clusters are obtained by direct reaction of solid state precursors in aqueous KCN solutions. Low dimensional frameworks are subsequently obtained by recrystallisation of hexacyano M6 clusters with transition elements. The functionalisation of cluster proceeds in two steps. The first one consists in the replacement of apical halogens of cluster unit precursors by labile groups as CF3SO3 (triflate) or solvent molecules after solution reaction. The second one consists in the substitution of the labile groups by functionalised phenolate or pyridine ligands. 相似文献