Activation of Propargylic Alcohols Derived from Hormonal Steroids by the Indenyl−Ruthenium(II) Complex [RuCl(η5-C9H7)(PPh3)2]:  Experimental and Theoretical Evidence of an Allenylidene−Vinylvinylidene Equilibrium

A versatile approach to the valorization of propargylic alcohols is reported, enabling controlled access to three different products from the same starting materials. Firstly, a general method for the hydroamination of propargylic alcohols with anilines is described using gold catalysis to give 3-hydroxy imines with complete regioselectivity. These 3-hydroxyimines can be reduced to give 1,3-aminoalcohols with high syn seletivity. Alternatively, by using a catalytic quantity of aniline, 3-hydroxyketones can be obtained in high yield directly from propargylic alcohols. Further manipulation of the reaction conditions enables the selective formation of 3-aminoketones via a rearrangement/hydroamination pathway.

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Solvent-Ligand Interactions in Colloidal Nanocrystals

10.26434/chemrxiv.6447884 ◽

2018 ◽

Author(s):

Jonathan De Roo ◽

Nuri Yazdani ◽

Emile Drijvers ◽

Alessandro Lauria ◽

Jorick Maes ◽

...

Keyword(s):

Direct Method ◽

Line Broadening ◽

H Nmr ◽

Size Dependent ◽

Line Shape Analysis ◽

Wide Range ◽

Nanocrystal Synthesis ◽

Ligand Interactions ◽

Indispensable Tool ◽

Theoretical Evidence

Although solvent-ligand interactions play a major role in nanocrystal synthesis, dispersion formulation and assembly, there is currently no direct method to study this. Here we examine the broadening of 1H NMR resonances associated with bound ligands, and turn this poorly understood descriptor into a tool to assess solvent-ligand interactions. We show that the line broadening has both a homogeneous and a heterogeneous component. The former is nanocrystal-size dependent and the latter results from solvent-ligand interactions. Our model is supported by experimental and theoretical evidence that correlates broad NMR lines with poor ligand solvation. This correlation is found across a wide range of solvents, extending from water to hexane, for both hydrophobic and hydrophilic ligand types, and for a multitude of oxide, sulfide and selenide nanocrystals. Our findings thus put forward NMR line shape analysis as an indispensable tool to form, investigate and manipulate nanocolloids.

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NEUROBLASTOMA IMMUNOTHERAPY

Problems in oncology ◽

10.37469/0507-3758-2019-65-2-181-187 ◽

2019 ◽

Vol 65 (2) ◽

pp. 181-187

Author(s):

Aleksandr Druy ◽

Svetlana Kuleva

Keyword(s):

T Cells ◽

Monoclonal Antibodies ◽

High Risk ◽

Checkpoint Inhibitors ◽

Innate And Adaptive Immunity ◽

Car T Cells ◽

Car T ◽

Membrane Antigens ◽

Theoretical Evidence ◽

Blocking Antibodies

The recent data about innate and adaptive immunity against neuroblastoma are described in the article. The era of neuroblastoma immunotherapy started since the evidence of anti-GD2 monoclonal antibodies efficiency. Nowadays monoclonal antibodies against GD2 are introduced into schemes of maintenance therapy for high-risk neuroblastoma patients. Developing of T-cells expressing chimeric antigen receptor (CAR-T cells) directed to membrane antigens is the perspective of neuroblastoma immunotherapy. PD1/PD-L1 blocking antibodies as immune checkpoint inhibitors have the theoretical evidence of potential effectiveness. Application of immunotherapeutic approaches in high-risk neuroblastoma patients together with conventional multimodal therapies requires further investigation.

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