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101.
An acylation‐Finkelstein approach to radioiodination of bioactives: The role of amide group anchimeric assistance 下载免费PDF全文
Richard Fjellaksel Damir Dugalic Taye B. Demissie Patrick J. Riss Ole‐Kristian Hjelstuen Rune Sundset Jørn H. Hansen 《Journal of Physical Organic Chemistry》2018,31(7)
Herein, we report a straightforward sequential acylation‐Finkelstein approach to achieve iodination of amine containing bioactives. The utility was demonstrated by successful radiolabelling with 123I in high radiochemical yield. Moreover, microwave‐assisted Finkelstein reaction can be employed to enhance conversion and reaction rates to obtain the desired iodides. The method is of interest for radioiodination of amine‐containing bioactives. The mechanistic details of the iodination process were studied by kinetics and density functional theory calculations, which revealed the mechanistic complexity of the reaction involving amide group anchimeric assistance. We disclose a number of fundamental aspects of amide group anchimeric assistance in substitution reactions. 相似文献
102.
Avdic Senada Beganovic Adnan Lagumdzija Armin Pehlivanovic Beco Demirovic Damir Kadic Irma 《Journal of Radioanalytical and Nuclear Chemistry》2019,320(3):535-542
Journal of Radioanalytical and Nuclear Chemistry - This paper deals with the first study of the indoor to outdoor ambient dose equivalent rates ratio measured in and around the historic objects at... 相似文献
103.
Damir Vuki?evi? Sonja Nikoli? Nenad Trinajsti? 《Journal of mathematical chemistry》2009,45(2):538-543
The definition of the path-Zagreb matrix for (chemical) trees PZ and its generalization to any (molecular) graph is presented. Additionally, the upper bound of , where G
n
is a graph with n vertices is given. 相似文献
104.
The Anti-Kekulé number of a connected graph G is the smallest number of edges that have to be removed from G in such way that G remains connected but it has no Kekulé structures. In this paper it is proved that the Anti-Kekulé number of all fullerenes
is either 3 or 4 and that for each leapfrog fullerene the Anti-Kekulé number can be established by observing finite number
of cases not depending on the size of the fullerene. 相似文献
105.
Klavdija Kutnar Dragan Marušič Damir Vukičević 《Journal of mathematical chemistry》2009,45(2):406-416
It is shown that given a fullerene F with the number of vertices n divisible by 4, and such that no two pentagons in F share an edge, the corresponding leapfrog fullerene Le(F) contains a long cycle of length 3n − 6 missing out only one hexagon. 相似文献
106.
A discrete time invariant linear state/signal system Σ with a Hilbert state space and a Kren signal space has trajectories (x(),w()) that are solutions of the equation , where F is a bounded linear operator from into with a closed domain whose projection onto is all of . This system is passive if the graph of F is a maximal nonnegative subspace of the Kren space . The future behavior of a passive system Σ is the set of all signal components w() of trajectories (x(),w()) of Σ on with x(0)=0 and . This is always a maximal nonnegative shift-invariant subspace of the Kren space , i.e., the space endowed with the indefinite inner product inherited from . Subspaces of with this property are called passive future behaviors. In this work we study passive state/signal systems and passive behaviors (future, full, and past). In particular, we define and study the input and output maps of a passive state/signal system, and the past/future map of a passive behavior. We then turn to the inverse problem, and construct two passive state/signal realizations of a given passive future behavior , one of which is observable and backward conservative, and the other controllable and forward conservative. Both of these are canonical in the sense that they are uniquely determined by the given data , in contrast earlier realizations that depend not only on , but also on some arbitrarily chosen fundamental decomposition of the signal space . From our canonical realizations we are able to recover the two standard de Branges–Rovnyak input/state/output shift realizations of a given operator-valued Schur function in the unit disk. 相似文献
107.
Damir Z. Arov 《Journal of Functional Analysis》2009,256(12):3892-3327
Let Z be a maximal nonnegative subspace of a Kre?n space X, and let X/Z be the quotient of X modulo Z. Define
H(Z)={h∈X/Z|sup{−X[x,x]|x∈h}<∞}. 相似文献
108.
The recently introduced atom-bond connectivity (ABC) index has been applied up to now to study the stability of alkanes and the strain energy of cycloalkanes. Here, mathematical properties of the ABC index of trees are studied. Chemical trees with extremal ABC values are found. In addition, it has been proven that, among all trees, the star tree, Sn, has the maximal ABC value. 相似文献
109.
A passive linear discrete time invariant s/s (state/signal) system Σ=(V;X,W) consists of a Hilbert (state) space X, a Kre?n (signal) space W, a maximal nonnegative (generating) subspace V of the Kre?n space K:=−X[?]X[?]W. The sets of trajectories (x(⋅);w(⋅)) generated by V on the discrete time intervals I⊂Z are defined by
110.
Damir Barisic David Schneider Ccilia Maichle‐Mssmer Reiner Anwander 《Angewandte Chemie (International ed. in English)》2019,58(5):1515-1518
The half‐open rare‐earth‐metal aluminabenzene complexes [(1‐Me‐3,5‐tBu2‐C5H3Al)(μ‐Me)Ln(2,4‐dtbp)] (Ln=Y, Lu) are accessible via a salt metathesis reaction employing Ln(AlMe4)3 and K(2,4‐dtbp). Treatment of the yttrium complex with B(C6F5)3 and tBuCCH gives access to the pentafluorophenylalane complex [{1‐(C6F5)‐3,5‐tBu2‐C5H3Al}{μ‐C6F5}Y{2,4‐dtbp}] and the mixed vinyl acetylide complex [(2,4‐dtbp)Y(μ‐η1:η3‐2,4‐tBu2‐C5H4)(μ‐CCtBu)AlMe2], respectively. 相似文献