Single-step formulation of levodopa-based nanotheranostics – strategy for ultra-sensitive high longitudinal relaxivity MRI guided switchable therapeutics

We report here that a series of O-bridged ring fused spiro piperidone-cyclopropane derivatives 3 can be constructed in a single step by the one-pot reaction of 1-acylcyclopropanecarboxamides 1 with polarized...

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Comparative study of different catalysts for the direct conversion of cellulose to sorbitol

Green Processing and Synthesis ◽

10.1515/gps-2014-0091 ◽

2015 ◽

Vol 4 (2) ◽

Cited By ~ 4

Author(s):

Lucília S. Ribeiro ◽

José J.M. Órfão ◽

Manuel Fernando R. Pereira

Keyword(s):

Direct Conversion ◽

Single Step ◽

Raw Material ◽

Added Value ◽

Supported Metal Catalysts ◽

One Pot ◽

Hydrolytic Hydrogenation ◽

Renewable Raw Material ◽

Pre Treatment ◽

The One

AbstractThe catalytic conversion of lignocellulosic biomass to obtain high added value compounds and fuels is a rapidly developing field. Given the abundance of this renewable raw material and its reduced impact on the food chain, it is an attractive source for obtaining chemicals or fuels in the context of a sustainable economy. In this work, bi-functional catalysts were developed that were capable of performing in a single step the hydrolysis and hydrogenation of cellulose to produce compounds that may be used in the production of fine chemicals or easily converted into fuels (e.g., sorbitol). Different activated carbon (AC) supported metal catalysts were examined for the one-pot hydrolytic hydrogenation of cellulose. Among the prepared catalysts, 0.4% Ru/AC was shown to be the most active and selective for the conversion of cellulose into sorbitol. When microcrystalline cellulose was used, a conversion of 32% was reached after 5 h of reaction, with a selectivity to sorbitol of 30%. Moreover, ball-milled cellulose allowed attaining conversions over 50%, with selectivities to sorbitol of 45%. The results obtained showed that Ru/AC is effective for the hydrolytic hydrogenation of cellulose to sugar alcohols and that the conversion can be greatly improved by using the substrate after pre-treatment by ball-milling.

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2-Ketoglutarate-Generated In Vitro Enzymatic Biosystem Facilitates Fe(II)/2-Ketoglutarate-Dependent Dioxygenase-Mediated C–H Bond Oxidation for (2s,3r,4s)-4-Hydroxyisoleucine Synthesis

International Journal of Molecular Sciences ◽

10.3390/ijms21155347 ◽

2020 ◽

Vol 21 (15) ◽

pp. 5347

Author(s):

Xiao-Ran Jing ◽

Huan Liu ◽

Yao Nie ◽

Yan Xu

Keyword(s):

Amino Acids ◽

Raw Materials ◽

Cascade Reaction ◽

Single Step ◽

One Pot ◽

Bond Functionalization ◽

Hydroxy Amino ◽

Enzymatic Systems ◽

The One

Fe(II)/2-ketoglutarate-dependent dioxygenase (Fe(II)/2-KG DO)-mediated hydroxylation is a critical type of C–H bond functionalization for synthesizing hydroxy amino acids used as pharmaceutical raw materials and precursors. However, DO activity requires 2-ketoglutarate (2-KG), lack of which reduces the efficiency of Fe(II)/2-KG DO-mediated hydroxylation. Here, we conducted multi-enzymatic syntheses of hydroxy amino acids. Using (2s,3r,4s)-4-hydroxyisoleucine (4-HIL) as a model product, we coupled regio- and stereo-selective hydroxylation of l-Ile by the dioxygenase IDO with 2-KG generation from readily available l-Glu by l-glutamate oxidase (LGOX) and catalase (CAT). In the one-pot system, H2O2 significantly inhibited IDO activity and elevated Fe2+ concentrations of severely repressed LGOX. A sequential cascade reaction was preferable to a single-step process as CAT in the former system hydrolyzed H2O2. We obtained 465 mM 4-HIL at 93% yield in the two-step system. Moreover, this process facilitated C–H hydroxylation of several hydrophobic aliphatic amino acids to produce hydroxy amino acids, and C–H sulfoxidation of sulfur-containing l-amino acids to yield l-amino acid sulfoxides. Thus, we constructed an efficient cascade reaction to produce 4-HIL by providing prerequisite 2-KG from cheap and plentiful l-Glu and developed a strategy for creating enzymatic systems catalyzing 2-KG-dependent reactions in sustainable bioprocesses that synthesize other functional compounds.

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Single-Step Organization of Plasmonic Gold Metamaterials with Self-Assembled DNA Nanostructures

Research ◽

10.34133/2019/7403580 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10 ◽

Cited By ~ 7

Author(s):

Shaokang Ren ◽

Jun Wang ◽

Chunyuan Song ◽

Qian Li ◽

Yanjun Yang ◽

...

Keyword(s):

Large Scale ◽

Single Step ◽

High Yield ◽

Great Promise ◽

Dna Nanostructures ◽

One Pot ◽

Dna Tiles ◽

Surface Enhanced Raman ◽

Self Assembled ◽

The One

Self-assembled DNA nanostructures hold great promise as nanoscale templates for organizing nanoparticles (NPs) with near-atomistic resolution. However, large-scale organization of NPs with high yield is highly desirable for nanoelectronics and nanophotonic applications. Here, we design five-strand DNA tiles that can readily self-assemble into well-organized micrometer-scale DNA nanostructures. By organizing gold nanoparticles (AuNPs) on these self-assembled DNA nanostructures, we realize the fabrication of one- and two-dimensional Au nanostructures in single steps. We further demonstrate the one-pot synthesis of Au metamaterials for highly amplified surface-enhanced Raman Scattering (SERS). This single-step and high-yield strategy thus holds great potential for fabricating plasmonic metamaterials.

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A Series of Metal-Organic Frameworks for Selective CO2 Capture and Catalytic Oxidative Carboxylation of Olefins

10.26434/chemrxiv.7068509 ◽

2018 ◽

Author(s):

Huong T. D. Nguyen ◽

Y B. N. Tran ◽

Hung N. Nguyen ◽

Tranh C. Nguyen ◽

Felipe Gándara ◽

...

Keyword(s):

Room Temperature ◽

Gas Adsorption ◽

New Materials ◽

One Pot ◽

Acid Gas ◽

Naphthalene Diimide ◽

Styrene Carbonate ◽

Metal Organic ◽

Adsorption Of Co ◽

The One

<p>Three novel lanthanide metal˗organic frameworks (Ln-MOFs), namely MOF-590, -591, and -592 were constructed from a naphthalene diimide tetracarboxylic acid. Gas adsorption measurements of MOF-591 and -592 revealed good adsorption of CO<sub>2</sub> (low pressure, at room temperature) and moderate CO<sub>2</sub> selectivity over N<sub>2</sub> and CH<sub>4</sub>. Accordingly, breakthrough measurements were performed on a representative MOF-592, in which the separation of CO<sub>2</sub> from binary mixture containing N<sub>2</sub> and CO<sub>2</sub> was demonstrated without any loss in performance over three consecutive cycles. Moreover, MOF-590, MOF-591, and MOF-592 exhibited catalytic activity in the one-pot synthesis of styrene carbonate from styrene and CO<sub>2</sub> under mild conditions (1 atm CO<sub>2</sub>, 80 °C, and solvent-free). Among the new materials, MOF-590 revealed a remarkable efficiency with exceptional conversion (96%), selectivity (95%), and yield (91%). </p><br>

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A Short Synthesis of (+)-Brefeldin C via Enantioselective Radical Hydroalkynylation

10.26434/chemrxiv.8397731.v1 ◽

2019 ◽

Author(s):

Lars Gnägi ◽

Severin Vital Martz ◽

Daniel Meyer ◽

Robin Marc Schärer ◽

Philippe Renaud

Keyword(s):

Total Synthesis ◽

Natural Product ◽

Oxidation State ◽

Single Step ◽

Radical Process ◽

Target Molecule ◽

Short Synthesis ◽

The One

<div><div><div><div><p>A very concise total synthesis of (+)-brefeldin C starting from 2-furanylcyclopentene is described. This approach is based on an unprecedented enantioselective radical hydroalkynylation process to introduce the two cyclopentane stereocenters in a single step. The use of a furan substituent allows to achieve a high trans diastereoselectivity during the radical process and it contains the four carbon atoms C1–C4 of the natural product in an oxidation state closely related to the one of the target molecule. The eight-step synthesis require six product purifications and it provides (+)-brefeldin C in 18% overall yield.</p></div></div></div></div>

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A Study on the Rearrangement of Dialkyl 1-Aryl-1-hydroxymethylphosphonates to Benzyl Phosphates

Current Organic Chemistry ◽

10.2174/1385272824666200226114306 ◽

2020 ◽

Vol 24 (4) ◽

pp. 465-471 ◽

Cited By ~ 2

Author(s):

Zita Rádai ◽

Réka Szabó ◽

Áron Szigetvári ◽

Nóra Zsuzsa Kiss ◽

Zoltán Mucsi ◽

...

Keyword(s):

Quantum Chemical ◽

Room Temperature ◽

Phase Transfer ◽

One Pot ◽

Substrate Dependence ◽

Triethylbenzylammonium Chloride ◽

One Step ◽

The Pudovik Reaction ◽

The One ◽

Solid Liquid

The phospha-Brook rearrangement of dialkyl 1-aryl-1-hydroxymethylphosphonates (HPs) to the corresponding benzyl phosphates (BPs) has been elaborated under solid-liquid phase transfer catalytic conditions. The best procedure involved the use of triethylbenzylammonium chloride as the catalyst and Cs2CO3 as the base in acetonitrile as the solvent at room temperature. The substrate dependence of the rearrangement has been studied, and the mechanism of the transformation under discussion was explored by quantum chemical calculations. The key intermediate is an oxaphosphirane. The one-pot version starting with the Pudovik reaction has also been developed. The conditions of this tandem transformation were the same, as those for the one-step HP→BP conversion.

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An Overview of the One-pot Synthesis of Imidazolines

Current Organic Chemistry ◽

10.2174/1385272824999201001153735 ◽

2020 ◽

Vol 24 (20) ◽

pp. 2341-2355

Author(s):

Thaipparambil Aneeja ◽

Sankaran Radhika ◽

Mohan Neetha ◽

Gopinathan Anilkumar

Keyword(s):

Asymmetric Catalysis ◽

Organic Compounds ◽

Ring Opening ◽

Ecological Impact ◽

Chiral Auxiliary ◽

One Pot ◽

One Pot Synthesis ◽

The One ◽

Synthetic Intermediate ◽

Heterocyclic Moiety

One-pot syntheses are a simple, efficient and easy methodology, which are widely used for the synthesis of organic compounds. Imidazoline is a valuable heterocyclic moiety used as a synthetic intermediate, chiral auxiliary, chiral catalyst and a ligand for asymmetric catalysis. Imidazole is a fundamental unit of biomolecules that can be easily prepared from imidazolines. The one-pot method is an impressive approach to synthesize organic compounds as it minimizes the reaction time, separation procedures, and ecological impact. Many significant one-pot methods such as N-bromosuccinimide mediated reaction, ring-opening of tetrahydrofuran, triflic anhydrate mediated reaction, etc. were reported for imidazoline synthesis. This review describes an overview of the one-pot synthesis of imidazolines and covers literature up to 2020.

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Synthesis and Kinetics of Highly Substituted Piperidines in the Presence of Tartaric Acid as a Catalyst

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207321666180228115130 ◽

2018 ◽

Vol 21 (4) ◽

pp. 302-311

Author(s):

Younes Ghalandarzehi ◽

Mehdi Shahraki ◽

Sayyed M. Habibi-Khorassani

Keyword(s):

Ambient Temperature ◽

Tartaric Acid ◽

Aromatic Aldehydes ◽

One Pot ◽

Rate Determining Step ◽

State Approximation ◽

Solvent Free Conditions ◽

Steady State Approximation ◽

Absorbance Changes ◽

The One

Aim & Scope: The synthesis of highly substituted piperidine from the one-pot reaction between aromatic aldehydes, anilines and β-ketoesters in the presence of tartaric acid as a catalyst has been investigated in both methanol and ethanol media at ambient temperature. Different conditions of temperature and solvent were employed for calculating the thermodynamic parameters and obtaining an experimental approach to the kinetics and mechanism. Experiments were carried out under different temperature and solvent conditions. Material and Methods: Products were characterized by comparison of physical data with authentic samples and spectroscopic data (IR and NMR). Rate constants are presented as an average of several kinetic runs (at least 6-10) and are reproducible within ± 3%. The overall rate of reaction is followed by monitoring the absorbance changes of the products versus time on a Varian (Model Cary Bio- 300) UV-vis spectrophotometer with a 10 mm light-path cell. Results: The best result was achieved in the presence of 0.075 g (0.1 M) of catalyst and 5 mL methanol at ambient temperature. When the reaction was carried out under solvent-free conditions, the product was obtained in a moderate yield (25%). Methanol was optimized as a desirable solvent in the synthesis of piperidine, nevertheless, ethanol in a kinetic investigation had none effect on the enhancement of the reaction rate than methanol. Based on the spectral data, the overall order of the reaction followed the second order kinetics. The results showed that the first step of the reaction mechanism is a rate determining step. Conclusion: The use of tartaric acid has many advantages such as mild reaction conditions, simple and readily available precursors and inexpensive catalyst. The proposed mechanism was confirmed by experimental results and a steady state approximation.

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