Four-fold click reactions: Generation of tetrahedral methane- and adamantane-based building blocks for higher-order molecular assemblies

2009 ◽  
Vol 7 (22) ◽  
pp. 4734 ◽  
Author(s):  
Oliver Plietzsch ◽  
Christine Inge Schilling ◽  
Mariyan Tolev ◽  
Martin Nieger ◽  
Clemens Richert ◽  
...  
Keyword(s):  
Building Blocks ◽  
Higher Order ◽  
Molecular Assemblies ◽  
Click Reactions

Microsized Structures Fabricated with Nanoparticles as Building Blocks

1998 ◽  
Vol 536 ◽  
Author(s):  
Yongchi Tian ◽  
A. D. Dinsmore ◽  
S. B. Qadri ◽  
B. R. Ratna
Keyword(s):  
Radial Growth ◽  
Building Blocks ◽  
Higher Order ◽  
Surfactant Templating ◽  
Order Structures

AbstractHere we report a nanoparticulate route to Y2O3 nanofibers (~50 nm in diameter and a few micrometers in length) and for the radial growth of ZnS spheres (200-800 nm diameter). Well-defined higher order structures are developed upon thermostatically aging the dispersions of monomeric nanocrystals. The shapes of the “macromolecules„ are correlated to primary monomeric nanocrystallites, the growing time and temperature, and surfactant templating agents. It is anticipated that this approach should inspire fabrication of nanoparticulate structures by using primary nanoparticles as monomers.

Synthesis of Sterically Congested Carbamates of Carbohydrates through Organic Base Catalysis

Synthesis ◽  
2019 ◽  
Vol 51 (15) ◽  
pp. 2897-2908 ◽  
Author(s):  
Anji Chen ◽  
Dan Wang ◽  
Lalith P. Samankumara ◽  
Guijun Wang
Keyword(s):  
Hydroxy Group ◽  
Current Method ◽  
Building Blocks ◽  
Base Catalysis ◽  
Organic Base ◽  
Molecular Assemblies ◽  
Effective Catalyst ◽  
Organic Bases ◽  
Derivatives Of ◽  
General Method

4,6-O-Benzylidene acetal protected α-methoxy d-glucose and d-glucosamine are useful building blocks for the syntheses of carbohydrate derivatives and functional molecular assemblies. In this research, we have developed a general method for the preparation of C-3 carbamate derivatives of densely functionalized glucose and glucosamine with isocyanates using organic bases as catalysts. Without a suitable catalyst, the C-3 hydroxy group of the glucosamine derivative could not be converted into the corresponding carbamates when treated with isocyanates. Several organic bases were screened as the catalysts for the reactions, and we discovered that 5.0 mol% of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) was an effective catalyst for the carbamoylation reaction. A library of both alkyl and aryl carbamate derivatives of the two sterically congested carbohydrates have been effectively synthesized using the current method.

“Chemistry-on-the-complex”: functional RuIIpolypyridyl-type sensitizers as divergent building blocks

2018 ◽  
Vol 47 (20) ◽  
pp. 7577-7627 ◽  
Author(s):  
Tina Mede ◽  
Michael Jäger ◽  
Ulrich S. Schubert
Keyword(s):  
Solar Cells ◽  
Energy Conversion ◽  
Dye Sensitized Solar Cells ◽  
Building Blocks ◽  
Molecular Assemblies ◽  
Ruthenium Polypyridyl ◽  
Dye Sensitized ◽  
Biomedical Diagnosis ◽  
Sensitized Solar Cells

Ruthenium polypyridyl type complexes are potent photoactive compounds, and have found – among others – a broad range of important applications in the fields of biomedical diagnosis and phototherapy, energy conversion schemes such as dye-sensitized solar cells (DSSCs) and molecular assemblies for tailored photo-initiated processes.

scholarly journals A fast and versatile cross-linking strategy via o-phthalaldehyde condensation for mechanically strengthened and functional hydrogels

2020 ◽  
Author(s):  
Zhen Zhang ◽  
Chaoliang He ◽  
Yan Rong ◽  
Hui Ren ◽  
Tianran Wang ◽  
...  
Keyword(s):  
Condensation Reaction ◽  
Building Blocks ◽  
Order Rate Constant ◽  
Cross Linking ◽  
Click Reactions ◽  
Oxime Formation ◽  
Cross Links ◽  
Poly Ethylene ◽  
Molecule Model ◽  
First Time

Abstract Fast and catalyst-free cross-linking strategy is of great significance for construction of covalently cross-linked hydrogels. Here, we report the condensation reaction between o-phthalaldehyde (OPA) and N-nucleophiles (primary amine, hydrazide and aminooxy) for hydrogel formation for the first time. When four-arm poly(ethylene glycol) (4aPEG) capped with OPA was mixed with various N-nucleophile-terminated 4aPEG as building blocks, hydrogels were formed with superfast gelation rate, higher mechanical strength and markedly lower critical gelation concentrations, compared to benzaldehyde-based counterparts. Small molecule model reactions indicate the key to these cross-links is the fast formation of heterocycle phthalimidine product or isoindole (bis)hemiaminal intermediates, depending on the N-nucleophiles. The second-order rate constant for the formation of phthalimidine linkage (4.3 M−1 s−1) is over 3000 times and 200 times higher than those for acylhydrazone and oxime formation from benzaldehyde, respectively, and comparable to many cycloaddition click reactions. Based on the versatile OPA chemistry, various hydrogels can be readily prepared from naturally derived polysaccharides, proteins or synthetic polymers without complicated chemical modification. Moreover, biofunctionality is facilely imparted to the hydrogels by introducing amine-bearing peptides via the reaction between OPA and amino group.

scholarly journals Investigation of the Reactivity of 1-Azido-3-Iodobicyclo[1.1.1]pentane under “Click” Reaction Conditions

2020 ◽  
Author(s):  
Elisabeth Sitte ◽  
Brendan Twamley ◽  
nitika grover ◽  
Mathias Senge
Keyword(s):  
Click Reaction ◽  
Chemical Properties ◽  
Building Blocks ◽  
Dipolar Cycloaddition ◽  
Coupling Reactions ◽  
Reaction Conditions ◽  
One Pot ◽  
Click Reactions ◽  
Drug Molecules ◽  
Physical And Chemical

The bicyclo[1.1.1]pentane (BCP) unit exhibits special physical and chemical properties and is under scrutiny as a bioisostere in drug molecules. We employed methodologies for the synthesis of different BCP triazole building blocks from one precursor, 1-azido-3-iodobicyclo[1.1.1]pentane, by Cu(I)-catalyzed 1,3-dipolar cycloaddition (“click”) reactions and integrated cycloaddition-Sonogashira coupling reactions. Thereby, we accessed three classes of substituted BCP derivatives: 1,4-disubstituted triazoles, 5-iodo-1,4,5-trisubstituted triazoles and 5-alkynylated 1,4,5-trisubstituted triazoles. This gives entry to the synthesis of multiply substituted BCP triazoles either on a modular or a one-pot basis. These methodologies were further utilized for appending large chromophoric porphyrin moieties onto the BCP core.

MAXWELL BRANE COSMOLOGY WITH HIGHER-ORDER STRING CURVATURE CORRECTIONS, A NONMINIMALLY COUPLED SCALAR FIELD, DARK MATTER–DARK ENERGY INTERACTION AND A VARYING SPEED OF LIGHT

2009 ◽  
Vol 18 (02) ◽  
pp. 289-318 ◽  
Author(s):  
R. A. EL-NABULSI
Keyword(s):  
Dark Matter ◽  
Dark Energy ◽  
Scalar Field ◽  
Friedmann Equation ◽  
Building Blocks ◽  
Higher Order ◽  
Alternative Theory ◽  
Speed Of Light ◽  
Energy Interaction ◽  
Curvature Term

We investigate the cosmological effects of an alternative theory of gravity on the four-dimensional Randall–Sundrum braneworld of type II with a higher-order string curvature term added to the action. We discuss the possibility of a varying speed of light, which has recently attracted considerable attention, in the presence a Maxwell field and of a dynamically evolving bulk scalar field nonminimally coupled to scalar curvature in a quadratic form, together with a dark matter–dark energy interaction term. After deriving the modified Friedmann equation on the brane, as well as the scalar field equations, we then analyze the dynamical equations obtained so far. Special attention is paid to scaling solutions which could be important building blocks in constructing the models of dark energy. The constructed model exhibits several features of cosmological and astrophysical interest for both the early and the late universe, consistent with recent observations, in particular the ones concerned with celerity of light, four and five gravitational constants, black hole masses and entropies.

scholarly journals Single molecule protein stabilisation translates to macromolecular mechanics of a protein network

Soft Matter ◽  
2020 ◽  
Vol 16 (27) ◽  
pp. 6389-6399 ◽  
Author(s):  
Matt D. G. Hughes ◽  
Sophie Cussons ◽  
Najet Mahmoudi ◽  
David J. Brockwell ◽  
Lorna Dougan
Keyword(s):  
Single Molecule ◽  
Building Blocks ◽  
Globular Proteins ◽  
Molecular Properties ◽  
Protein Network ◽  
Biological Functions ◽  
Molecular Assemblies ◽  
Protein Stabilisation ◽  
Macromolecular Mechanics

Folded globular proteins are attractive building blocks for biomaterials as their robust structures carry out diverse biological functions. These biomaterials are ideal to study the translation of molecular properties to multi-molecular assemblies.

Template-based fabrication of spatially organized 3D bioactive constructs using magnetic low-concentration gelation methacrylate (GelMA) microfibers

Soft Matter ◽  
2020 ◽  
Vol 16 (16) ◽  
pp. 3902-3913 ◽  
Author(s):  
Tao Sun ◽  
Yibing Yao ◽  
Qing Shi ◽  
Huaping Wang ◽  
Paolo Dario ◽  
...  
Keyword(s):  
Building Blocks ◽  
Higher Order ◽  
Low Concentration

A new template-based method to apply low-concentration GelMA microfibers as building blocks for higher-order cellular assembly.

Sign in / Sign up

Export Citation Format

Share Document