Synthesis of tridentate amine Pt(II) complexes and study of their reactions with purine and pyrimidine bases

1994 ◽  
Vol 72 (5) ◽  
pp. 1225-1229
Author(s):  
Fernande D. Rochon ◽  
Guylaine Laperrière
Keyword(s):  
The Other ◽  
New Method ◽  
Direct Reaction ◽  
Chloro Complexes ◽  
Methyl Group ◽  
Alkyl Groups ◽  
Nmr Techniques ◽  
Pyrimidine Bases ◽  
The One ◽  
Derivatives Of

Complexes of the type [Pt(L)X] where L is a tridentate N ligand and X = Cl or I, were synthesized and characterized. Three of the ligands are N-derivatives of diethylenetriamine, (2-aminoethyl)(N-dimethyl-2-aminoethyl)amine, (2-aminoethyl)(N-diethyl-2-aminoethyl)amine, and (2-aminoethyl)(N-methyl-2-aminoethyl)N-methylamine. The other two ligands are di(3-amino-propyl)amine and (2-aminoethyl)(3-aminopropyl)amine. A new method for the synthesis of the chloro complexes from the direct reaction of the amine with K2[PtCl4] was developed. The reactions of these five compounds with several purine and pyrimidine bases were studied by NMR techniques. The Pt(II) complexes containing two five-membered chelates were shown to be more reactive than the one containing two six-membered rings, while the complex containing one five- and one six-membered chelates showed intermediate reactivity. For the diethylenetriamine derivatives, the complexes containing ligands with two alkyl groups on the same terminal N atom were more reactive than the one containing one methyl group on a terminal N atom and one methyl group on a non-terminal N atom.

Optimal Camera Placement in a Virtual Environment

2021 ◽  
pp. 247-260
Author(s):  
Hocine Chebi
Keyword(s):  
Real Time ◽  
Virtual Environment ◽  
The Other ◽  
New Method ◽  
Camera Placement ◽  
Virtual Camera ◽  
Clear Vision ◽  
Transmission Of Information ◽  
The One ◽  
Visual Properties

Camera placement in a virtual environment consists of positioning and orienting a 3D virtual camera so as to respect a set of visual or cinematographic properties defined by the user. Carrying out this task is difficult in practice. Indeed, the user has a clear vision of the result he wants to obtain in terms of the arrangement of the objects in the image. In this chapter, the authors identify three areas of research that are relatively little covered by the literature dedicated to camera placement and which nevertheless appear essential. On the one hand, existing approaches offer little flexibility in both solving and describing a problem in terms of visual properties, especially when it has no solution. They propose a flexible solution method which computes the set of solutions, maximizing the satisfaction of the properties of the problem, whether it is over constrained or not. On the other hand, the existing methods calculate only one solution, even when the problem has several classes of equivalent solutions in terms of satisfaction of properties. They introduce the method of semantic volumes which computes the set of classes of semantically equivalent solutions and proposes a representative of each of them to the user. Finally, the problem of occlusion, although essential in the transmission of information, is little addressed by the community. Consequently, they present a new method of taking into account occlusion in dynamic real-time environments.

Synthesis of 2-Deoxy-β-D-ribonucleosides and 2,3-Dideoxy-β-D-pentofuranosides on Immobilized Bacterial Cells

1994 ◽  
Vol 59 (10) ◽  
pp. 2303-2330 ◽  
Author(s):  
Ivan Votruba ◽  
Antonín Holý ◽  
Hana Dvořáková ◽  
Jaroslav Günter ◽  
Dana Hocková ◽  
...  
Keyword(s):  
The Other ◽  
Bacterial Cells ◽  
Amino Groups ◽  
E Coli ◽  
Pyrimidine Series ◽  
Acceptor Activity ◽  
Dependent Strain ◽  
Pyrimidine Bases ◽  
Heterocyclic Bases ◽  
Derivatives Of

Alginate gel-entrapped cells of auxotrophic thymine-dependent strain of E. coli catalyze the transfer of 2-deoxy-D-ribofuranosyl moiety of 2'-deoxyuridine to purine and pyrimidine bases as well as their aza and deaza analogs. All experiments invariably gave β-anomers; in most cases, the reaction was regiospecific, affording N9-isomers in the purine and N1-isomers in the pyrimidine series. Also a 2,3-dideoxynucleoside can serve as donor of the glycosyl moiety. The acceptor activity of purine bases depends only little on substitution, the only condition being the presence of N7-nitrogen atom. On the other hand, in the pyrimidine series the activity is limited to only a narrow choice of mostly short 5-alkyl and 5-halogeno uracil derivatives. Heterocyclic bases containing amino groups are deaminated; this can be avoided by conversion of the base to the corresponding N-dimethylaminomethylene derivative which is then ammonolyzed. The method was verified by isolation of 9-(2-deoxy-β-D-ribofuranosyl) derivatives of adenine, guanine, 2-chloroadenine, 6-methylpurine, 8-azaadenine, 8-azaguanine, 1-deazaadenine, 3-deazaadenine, 1-(2-deoxy-β-D-ribofuranosyl) derivatives of 5-ethyluracil, 5-fluorouracil, and 9-(2,3-dideoxy-β-D-pentofuranosyl)hypoxanthine, 9-(2,3-dideoxy-β-D-pentofuranosyl)-6-methylpurine, and other nucleosides.

Polyhedral boron derivatives of porphyrins and phthalocyanines

2001 ◽  
Vol 05 (11) ◽  
pp. 767-781 ◽  
Author(s):  
VLADIMIR I. BREGADZE ◽  
IGOR B. SIVAEV ◽  
DETLEF GABEL ◽  
DIETER WÖHRLE
Keyword(s):  
Neutron Capture ◽  
Tumor Therapy ◽  
The Other ◽  
Medical Applications ◽  
Neutron Capture Therapy ◽  
Current Interest ◽  
Boron Compounds ◽  
Other Hand ◽  
The One ◽  
Derivatives Of

The synthesis of compounds containing polyhedral boron cages and porphyrin or phthalocyanine units connected covalently in one molecule is reviewed. The importance of these compounds arises, on the one hand, from the use of polyhedral boron derivatives in neutron capture therapy for cancer; on the other hand, porphyrins and phthalocyanines are known as photosensitizers in photodynamic tumor therapy. Current interest in the binding of polyhedral boron compounds to porphyrins and phthalocyanines is due to the observation that porphyrins and phthalocyanines show improved uptake and good persistence in tissues. Medical applications of compounds containing polyhedral boron cages and porphyrin or phthalocyanine units in one molecule are briefly discussed.

Two New Reagents for the Fluorescence Derivatization of NH and OH Containing Compounds

1983 ◽  
Vol 38 (2) ◽  
pp. 248-250 ◽  
Author(s):  
Reinhold Wintersteiger ◽  
Otto S. Wolfbeis
Keyword(s):  
Ring Closure ◽  
The Other ◽  
Fluorescence Derivatization ◽  
Methyl Group ◽  
Derivatives Of

Abstract The synthesis of three new reagents, namely the bromomethyl derivatives of a pyrano-[3,2-c]benzopyran (2b) and of 11H-pyrido[1,2-b]quinazolin-11-one (3b, d) is described. Introduction of the reactive bromomethyl group was accomplished in one case (2 b) by a ring closure reaction using ethyl y-chloroacetoacetate, and in the other cases (3 b, d) by bromination of a methyl group using N-bromosuccinimide. 2 b is suitable for the derivatization of barbiturates, whilst 3d reacts with oxygen nucleophiles like alcohols, phenols or carboxylates.

A New Method and Device for Temperature Measurement Using One-Dimensional Heat Equation

1994 ◽  
Author(s):  
Nicolae A. Damean
Keyword(s):  
Heat Equation ◽  
Temperature Measurement ◽  
Low Temperatures ◽  
Principal Component ◽  
The Other ◽  
New Method ◽  
Gradient Algorithm ◽  
One Dimensional ◽  
The One ◽  
The Mathematical Model

Abstract A new method and device for temperature measurement are presented. The method reduces the measurement of the unknown temperature to the solving of an optimal control problem, using a numerical computer. The device consists of a hardware part including some conventional transducers and a software one. The problem of temperature measurement, according to this method, is mathematically modelled by means of the one-dimensional heat equation, describing the heat transfer through the device. The principal component of the device is a rod. The variation of the temperature which is produced near one end of the rod is determined using some temperature measurements in the other end of the rod, the mathematical model and a type of gradient algorithm. This device works as an attenuator of high temperatures and as an amplifier of low temperatures.

Natural and Synthetic Rubber. XIV. A Structural Formula for Ebonite

1934 ◽  
Vol 7 (3) ◽  
pp. 520-524
Author(s):  
Thomas Midgley ◽  
Albert L. Henne ◽  
A. F. Shepard
Keyword(s):  
Carbon Atom ◽  
Structural Formula ◽  
The Other ◽  
Pyrolysis Products ◽  
Methyl Group ◽  
Synthetic Rubber ◽  
The One ◽  
Natural And Synthetic

Abstract A formula for ebonite has been proposed, where sulfur is linked to a carbon atom bearing a methyl group on the one side and to the next third carbon atom of the rubber chain on the other side This formula is based on a consideration of the pyrolysis products of ebonite.

scholarly journals Higgs inflation and its extensions and the further refining dS swampland conjecture

2021 ◽  
Vol 81 (12) ◽  
Author(s):  
Yang Liu
Keyword(s):  
Scalar Potential ◽  
Cosmological Parameters ◽  
The Other ◽  
De Sitter ◽  
Inflation Model ◽  
Link Type ◽  
Second Derivatives ◽  
The One ◽  
Derivatives Of ◽  
Inflationary Models

AbstractOn the one hand, Andriot and Roupec (Fortsch Phys, 1800105, 2019) proposed an alternative refined de Sitter conjecture, which gives a natural condition on a combination of the first and second derivatives of the scalar potential (Andriot and Roupec 2019). On the other hand, in our previous article (Liu in Eur Phys J Plus 136:901, 2021) , we have found that Palatini Higgs inflation model is in strong tension with the refined de Sitter swampland conjecture (Liu 2021). Therefore, following our previous research, in this article we examine if Higgs inflation model and its two variations: Palatini Higgs inflation and Higgs-Dilaton model (Rubio in Front Astron Space Sci, 10.3389/fspas.2018.00050, 2019) can satisfy the “further refining de Sitter swampland conjecture” or not. Based on observational data (Ade et al., Phys Rev Lett 121:221301, 2018; Akrami et al., Planck 2018 results. X. Constraints on inflation, arXiv:1807.06211 [astro-ph.CO], 2018; Aghanim et al., Planck 2018 results: VI. Cosmological parameters, arXiv:1807.06209 [astro-ph.CO], 2018), we find that these three inflationary models can always satisfy this new swampland conjecture if only we adjust the relevant parameters a, $$b = 1-a$$ b = 1 - a and q. Therefore, if the “further refining de Sitter swampland conjecture” does indeed hold, then the three inflationary models might all be in “landscape”.

scholarly journals D. A. Entin. Experiments with reconstruction of the facial skeleton (a new method of direct prosthetics in resection of the upper jaw). With Prof. S.S. Girgolav, Military Medical Academy., Gos. Izd., 1924, 158 pp., 16 figures and 1 drawing

1925 ◽  
Vol 21 (2) ◽  
pp. 214-215
Author(s):  
P. Glushkov
Keyword(s):  
Elastic Material ◽  
Individual Case ◽  
The Other ◽  
New Method ◽  
Facial Skeleton ◽  
Military Medical Academy ◽  
Dental Technician ◽  
Medical Academy ◽  
Upper Jaw ◽  
The One

On the one hand, Entin aimed to simplify the technique of making direct prostheses for the operation, making it accessible to an ordinary dental technician, and on the other hand, to construct a prosthesis that would meet the principle of exact morphological and anatomical-topographic individualization in each individual case. In pursuit of both these objectives, he developed a prosthesis in a soft, elastic material and made it inflatable and pneumatic according to Schiltski's idea.

scholarly journals Applying Rigor to Agile Research and Innovation Projects Guided by Product Development

2020 ◽  
Author(s):  
Alberto Tejero ◽  
Gonzalo León
Keyword(s):  
Product Development ◽  
The Other ◽  
New Method ◽  
Scientific Quality ◽  
Research And Innovation ◽  
Other Hand ◽  
Great Utility ◽  
Innovation Projects ◽  
The One

This article, as a main contribution, shows a new agile way to manage and monitor R&I projects, by monitoring product development. In addition, a new way of calculating the rigor of this type of projects is presented using the “3D rigor method”, based on obtaining the rigor measures of the product, process and reputation of the project researchers. Thanks to this new method, it is possible to know the rigor of an R&I project at any time during its development, which enables its monitoring and management to adapt it to the interests and needs of each situation. On the one hand, this method is presented as a tool of great utility for new researchers, since it will allow them to guide the development of their R&I project in an agile way, adjusted to the speed of the current times, while maintaining minimum levels of rigor and scientific quality. On the other hand, the method is highly recommended for all those organizations that promote and support the development of new R&I projects, enabling them to mentor and guide the projects towards the achievement of specific objectives and viable projects.

scholarly journals XIV. On some new derivatives of chloroform

1856 ◽  
Vol 7 ◽  
pp. 135-138 ◽  
Keyword(s):  
Hydrochloric Acid ◽  
Chemical Reactions ◽  
The Other ◽  
The One ◽  
Derivatives Of

According to the results of recent researches in the constitution of salts and the methods thence introduced of explaining chemical reactions, it is equally correct to represent such a reaction as that of hydrochloric acid on hydrate of potash, as consisting in an exchange of hydrogen of the one for potassium of the other, or of chlorine in one for peroxide of hydrogen in the other.

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