Tyrosine-Selective Bioconjugation with Iminoxyl Radicals

A novel Tyr-selective protein bioconjugation using the water-soluble persistent iminoxyl radical is described. The conjugation proceeded with high Tyr-selectivity and short reaction time under biocompatible conditions (room temperature in buffered media under air). The stability of the conjugates was tunable depending on the steric hindrance of iminoxyl. The presence of sodium ascorbate and/or light irradiation promoted traceless deconjugation, restoring the native Tyr structure. The method is applied to the synthesis of a protein-dye conjugate and further derivatization to azobenzene-modified peptides.

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Visible Light Assisted Hantzsch Reaction: Synthesis of Polycyclic Dihydropyridines

Letters in Organic Chemistry ◽

10.2174/1570178615666181107095151 ◽

2019 ◽

Vol 16 (8) ◽

pp. 676-682

Author(s):

Ankusab Noorahmadsab Nadaf ◽

Kalegowda Shivashankar

Keyword(s):

Reaction Time ◽

Light Intensity ◽

Ammonium Acetate ◽

Low Cost ◽

Aromatic Aldehydes ◽

Light Irradiation ◽

High Yield ◽

Short Reaction Time ◽

Green Protocol ◽

Dihydropyridine Derivatives

The polycyclic dihydropyridine nucleus represents the heterocyclic system of invaluable core motifs with wide applications in chemical, biological and physical properties. Although this kind of compounds have been extensively synthesized by other groups, the synthesis of these compounds under CFL light intensity were not explored. The synthesis of polycyclic dihydropyridine derivatives were achieved through the reaction of 4-hydroxycoumarin, aromatic aldehydes and ammonium acetate under CFL light irradiation conditions. A series of polycyclic dihydropyridine derivatives were prepared under CFL light irradiation conditions with high yield, short reaction time, ambient condition and without the use of catalyst. The results displayed an efficient method for the synthesis of polycyclic dihydropyridine derivatives. Clean profile, short reaction time, low cost and use of CFL light intensity instead of catalyst making it a genuinely green protocol.

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Hypervalent Iodine(III)-Catalyzed Epoxidation of β-Cyanostyrenes

Synthesis ◽

10.1055/s-0039-1690621 ◽

2019 ◽

Vol 51 (23) ◽

pp. 4473-4486 ◽

Cited By ~ 1

Author(s):

Saeesh R. Mangaonkar ◽

Fateh V. Singh

Keyword(s):

Reaction Time ◽

Room Temperature ◽

Hypervalent Iodine ◽

Short Reaction Time ◽

Convenient Approach

A convenient approach for the synthesis of β-cyanoepoxides is illustrated by iodine(III)-catalyzed epoxidation of electron-deficient β-cyanostyrenes, wherein the active catalytic iodine(III) species was generated in situ. The epoxidation of β-cyanostyrenes was performed using 10 mol% PhI as precatalyst in the presence of 2.0 equivalents Oxone as an oxidant and 2.4 equivalents of TFA as an additive at room temperature under ultrasonic radiations. The β-cyanoepoxides were isolated in good to excellent yields in a short reaction time.

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Synthesis of Epihalohydrins by Dehydrohalogenation of Glycerol Dihalohydrins - Utilization of a Basic Ion-Exchange Resin

Australian Journal of Chemistry ◽

10.1071/ch9921327 ◽

1992 ◽

Vol 45 (8) ◽

pp. 1327

Author(s):

M Dargelos ◽

ME Borredon ◽

A Gaset

Keyword(s):

Reaction Time ◽

Ion Exchange ◽

Room Temperature ◽

Exchange Resin ◽

Ion Exchange Resin ◽

Organic Medium ◽

Short Reaction Time ◽

Hydrolysis Of

Dehydrohalogenation of a mixture of glycerol 1,3- and 2,3-dihalohydrins by a strong basic ion-exchange resin (IRA 440 and A 26) at room temperature in an organic medium quantitatively leads to the corresponding epihalohydrin (1a; X = Cl), and (1b; X = Br) in a very short reaction time. Hydrolysis of the epihalohydrin does not occur under these conditions.

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Efficient Copper-Catalyzed Synthesis of Substituted Pyrazoles at Room Temperature

Synlett ◽

10.1055/s-0037-1610330 ◽

2018 ◽

Vol 29 (20) ◽

pp. 2689-2692 ◽

Cited By ~ 6

Author(s):

Haifeng Wang ◽

Xiangli Sun ◽

Shuangling Zhang ◽

Guanglu Liu ◽

Chunjie Wang ◽

...

Keyword(s):

Reaction Time ◽

Catalytic System ◽

Efficient Method ◽

Room Temperature ◽

Copper Catalyst ◽

Condensation Reaction ◽

Reaction Conditions ◽

Short Reaction Time ◽

Acid Catalyzed ◽

Substituted Pyrazoles

An efficient method for the synthesis of pyrazoles through a copper-catalyzed condensation reaction has been developed. The new catalytic system not only maintained a broad substrate scope but was also active under acid-free reaction conditions, overcoming the conventional requirement for an acid-catalyzed system. Furthermore, the copper catalyst enabled this reaction to be performed at room temperature and in a short reaction time.

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A Green, Expeditious, One-Pot Synthesis of 3, 4-Dihydropyrimidin-2(1H)-ones Using a Mixture of Phosphorus Pentoxide-Methanesulfonic Acid at Ambient Temperature

ISRN Organic Chemistry ◽

10.5402/2012/415645 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 6

Author(s):

Amulrao Borse ◽

Mahesh Patil ◽

Nilesh Patil ◽

Rohan Shinde

Keyword(s):

Reaction Time ◽

Ambient Temperature ◽

Room Temperature ◽

Simple Procedure ◽

Methanesulfonic Acid ◽

Phosphorus Pentoxide ◽

One Pot ◽

Short Reaction Time ◽

Solvent Free Conditions ◽

High Yields

An expeditious, one-pot method for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones using a mixture of phosphorus pentoxide-methanesulfonic acid (Eaton’s reagent) at room temperature under solvent-free conditions is described. The salient features of this method include short reaction time, green aspects, high yields, and simple procedure.

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Rapid Reduction of Alkenes and Alkynes over Pd Nanoparticles Supported on Sulfonated Porous Carbon

Journal of Chemistry ◽

10.1155/2013/268649 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7

Author(s):

Arash Shokrolahi ◽

Abbas Zali ◽

Kamal Ghani

Keyword(s):

Reaction Time ◽

Porous Carbon ◽

Room Temperature ◽

Heterogeneous Reaction ◽

Low Cost ◽

Pd Nanoparticles ◽

Rapid Reduction ◽

Short Reaction Time ◽

Novel Method ◽

High Yields

A novel method has been introduced for rapid reduction of alkenes and alkynes, which may be attractive for chemical industries. This method has some advantages such as simplicity and low cost of reactants. Pd supported on sulfonated porous carbon (SPC) was used as a new catalyst for reduction of alkenes and alkynes to the corresponding alkanes using sodium borohydride. The heterogeneous reaction was conducted in open air at room temperature to produce the desired saturated compounds in high yields (over 96%) and in short reaction time (15 minutes).

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A Study on Linseed Oil Modified Waterborne Polyurethane Coatings

Materials Science Forum ◽

10.4028/www.scientific.net/msf.686.528 ◽

2011 ◽

Vol 686 ◽

pp. 528-532 ◽

Cited By ~ 1

Author(s):

Jian Bing Chen ◽

Qiang Guo ◽

Jin Liang Sun ◽

Xian Li Shao ◽

Zhi Jun Nie

Keyword(s):

Weight Loss ◽

Reaction Time ◽

Room Temperature ◽

Linseed Oil ◽

Waterborne Polyurethane ◽

Polyurethane Coating ◽

Structure And Properties ◽

Polyurethane Coatings ◽

The Stability

The waterborne polyurethane coatings modified by linseed oil were prepared in a method of ammonolysis. The influence of reaction time and temperature of the linseed oil ammonolysis on structure and properties of the waterborne polyurethane coatings was investigated and discussed. It has been shown in this work that the preferred ammonolysis temperature would be 102~118°C, the reaction time could be about 80 min, and structure of the modified waterborne polyurethane was analysed by FTIR. The touch-dry time of the modified waterborne polyurethane with drier would be shorter than that of non-modified waterborne polyurethane, normally in a week, and the stability of the modified waterborne polyurethane coating in water could stand for 3 months under room temperature. The TGA results of the coatings showed that the weight loss started at about 294°C.

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Highly Efficient Recyclable Sol Gel Polymer Catalyzed One Pot Difunctionalization of Alkynes

Molecules ◽

10.3390/molecules23081879 ◽

2018 ◽

Vol 23 (8) ◽

pp. 1879

Author(s):

Justin Domena ◽

Carlos Chong ◽

Qiaxian Johnson ◽

Bhanu Chauhan ◽

Yalan Xing

Keyword(s):

Reaction Time ◽

Room Temperature ◽

Functional Group ◽

Sol Gel ◽

One Pot ◽

Short Reaction Time ◽

Metal Free ◽

Highly Efficient

Amino-bridged gel polymer P1 was discovered to catalyze alkyne halo-functionalization in excellent yields, regioselectivity, functional group compatibility, and recyclability. We have observed that both aromatic and aliphatic alkynes can be converted to α,α-dihalogenated ketones in the presence of polymer P1 under metal-free conditions at room temperature within a short reaction time.

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Phosphomolybdic Acid (PMA)-catalyzed One-pot Synthesis of 2,3- Dihydroquinazolines

Letters in Organic Chemistry ◽

10.2174/1570178615666181108104155 ◽

2019 ◽

Vol 16 (8) ◽

pp. 683-687

Author(s):

Chuanhuan Chen ◽

A. Xuejiao ◽

Xia Li ◽

Guoli Huang ◽

Bo Liu

Keyword(s):

Reaction Time ◽

Present Method ◽

Room Temperature ◽

Phosphomolybdic Acid ◽

New Method ◽

High Yield ◽

One Pot ◽

Short Reaction Time ◽

One Pot Synthesis

We have developed a new method for the synthesis of 2,3-dihydroquinazolin-4(1H)-ones in good to excellent yields via phosphomolybdic acid (PMA)-catalyzed cyclocondensation of 2- aminobenzamides with aldehydes or ketones in N,N-dimethylformamide (DMF) at room temperature. The present method proves to be efficient in terms of short reaction time, high yield, simple workup and easy purification.

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