Effect of the Carboxyl Functional Group at the Edges of Graphene on the Signal Sensitivity of Dopamine Detection

A modular approach was used in the synthesis of the 3-(diphenylamino)carbazolyl- functionalized 2-(4-(dimethylamino)benzylidene)-1H-indene-1,3(2H)-dione (DMABI) derivatives. For this purpose, carboxyl functional group was introduced into the framework of DMABI molecule. Additionally, a regioselective method for substitution of carbonyl group of DMABI with dicyanomethylene group was investigated and verified using the heteronuclear multiple bond correlation NMR spectra. Steglich esterification method was used to connect the 3‑(diphenylamino)carbazolyl moiety via an unconjugated spacer. The UV-Vis absorption spectra and molecular energy level data were obtained for the evaluation of the synthesized compounds as donor materials in bulk-heterojunction solar cells.

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Adsorption of Pesticidal Compounds Bearing a Single Carboxyl Functional Group and Biogenic Amines by Humic Fraction-Immobilized Silica Gel

Journal of Agricultural and Food Chemistry ◽

10.1021/jf400242c ◽

2013 ◽

Vol 61 (15) ◽

pp. 3600-3610 ◽

Cited By ~ 9

Author(s):

Cheng-Sheng Chen ◽

Shushi Chen

Keyword(s):

Biogenic Amines ◽

Silica Gel ◽

Functional Group ◽

Carboxyl Functional Group ◽

Humic Fraction

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Assessing the Conformational Equilibrium of Carboxylic Acid via QM and MD Studies on Acetic Acid

10.26434/chemrxiv.7374131.v1 ◽

2018 ◽

Author(s):

Victoria T. Lim ◽

Christopher I. Bayly ◽

Laszlo Fusti-Molnar ◽

David Mobley

Keyword(s):

Acetic Acid ◽

Molecular Modeling ◽

Carboxylic Acids ◽

Functional Group ◽

Careful Examination ◽

Hydrogen Atoms ◽

Biomolecular Systems ◽

General Belief ◽

Dynamics Simulations ◽

Carboxyl Functional Group

Accurate hydrogen placement in molecular modeling is crucial for studying the interactions and dynamics of biomolecular systems. It is difficult to locate hydrogen atoms from many experimental structural characterization approaches, such as due to the weak scattering of x-ray radiation. Hydrogen atoms are usually added and positioned in silico when preparing experimental structures for modeling and simulation. The carboxyl functional group is a prototypical example of a functional group that requires protonation during structure preparation. To our knowledge, when in their neutral form, carboxylic acids are typically protonated in the syn conformation by default in classical molecular modeling packages, with no consideration of alternative conformations, though we are not aware of any careful examination of this topic. Here, we investigate the general belief that carboxylic acids should always be protonated in the syn conformation. We calculate and compare the relative energetic stabilities of syn and anti acetic acid using ab initio quantum mechanical calculations and atomistic molecular dynamics simulations. We show that while the syn conformation is the preferred state, the anti state may in some cases also be present under normal NPT conditions in solution.

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Assessing the Conformational Equilibrium of Carboxylic Acid via QM and MD Studies on Acetic Acid

10.26434/chemrxiv.7374131 ◽

2018 ◽

Author(s):

Victoria T. Lim ◽

Christopher I. Bayly ◽

Laszlo Fusti-Molnar ◽

David Mobley

Keyword(s):

Acetic Acid ◽

Molecular Modeling ◽

Carboxylic Acids ◽

Functional Group ◽

Careful Examination ◽

Hydrogen Atoms ◽

Biomolecular Systems ◽

General Belief ◽

Dynamics Simulations ◽

Carboxyl Functional Group

Accurate hydrogen placement in molecular modeling is crucial for studying the interactions and dynamics of biomolecular systems. It is difficult to locate hydrogen atoms from many experimental structural characterization approaches, such as due to the weak scattering of x-ray radiation. Hydrogen atoms are usually added and positioned in silico when preparing experimental structures for modeling and simulation. The carboxyl functional group is a prototypical example of a functional group that requires protonation during structure preparation. To our knowledge, when in their neutral form, carboxylic acids are typically protonated in the syn conformation by default in classical molecular modeling packages, with no consideration of alternative conformations, though we are not aware of any careful examination of this topic. Here, we investigate the general belief that carboxylic acids should always be protonated in the syn conformation. We calculate and compare the relative energetic stabilities of syn and anti acetic acid using ab initio quantum mechanical calculations and atomistic molecular dynamics simulations. We show that while the syn conformation is the preferred state, the anti state may in some cases also be present under normal NPT conditions in solution.

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Bright Blue, Green, and Red Luminescence from Dye-Sensitized Core@Shell Upconversion Nanophosphors under 800 nm Near-Infrared Light

Materials ◽

10.3390/ma13235338 ◽

2020 ◽

Vol 13 (23) ◽

pp. 5338

Author(s):

A-Ra Hong ◽

Joon Soo Han ◽

Gumin Kang ◽

Hyungduk Ko ◽

Ho Seong Jang

Keyword(s):

Near Infrared ◽

Functional Group ◽

Infrared Light ◽

Core Shell ◽

Dye Sensitized ◽

Nir Light ◽

Light Excitation ◽

Red Luminescence ◽

Carboxyl Functional Group ◽

Bright Blue

In this study, Li-based blue- and green-emitting core@shell (C@S) upconversion nanophosphors (UCNPs) and NaGdF4-based red-emitting C@S UCNPs were synthesized, and IR-808 dyes were conjugated with the C@S UCNPs to enhance upconversion (UC) luminescence. The surface of the as-synthesized C@S UCNPs, which was originally capped with oleic acid, was modified with BF4− to conjugate the IR-808 dye having a carboxyl functional group to the surface of the UCNPs. After the conjugation with IR-808 dyes, absorbance of the UCNPs was significantly increased. As a result, dye-sensitized blue (B)-, green (G)-, and red (R)-emitting UCNPs exhibited 87-fold, 10.8-fold, and 110-fold enhanced UC luminescence compared with B-, G-, and R-emitting Nd3+-doped C@S UCNPs under 800 nm near-infrared (NIR) light excitation, respectively. Consequently, dye-sensitized UCNPs exhibiting strong UC luminescence under 800 nm NIR light excitation have high applicability in a variety of biological applications.

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Robust high-temperature potassium-ion batteries enabled by carboxyl functional group energy storage

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2110912118 ◽

2021 ◽

Vol 118 (35) ◽

pp. e2110912118

Author(s):

Xianlu Lu ◽

Xuenan Pan ◽

Dongdong Zhang ◽

Zhi Fang ◽

Shang Xu ◽

...

Keyword(s):

High Temperature ◽

Energy Storage ◽

Current Density ◽

Functional Group ◽

Specific Capacity ◽

Potassium Ion ◽

Large Radius ◽

High Current ◽

Capacity Retention ◽

Carboxyl Functional Group

The popularly reported energy storage mechanisms of potassium-ion batteries (PIBs) are based on alloy-, de-intercalation-, and conversion-type processes, which inevitably lead to structural damage of the electrodes caused by intercalation/de-intercalation of K+ with a relatively large radius, which is accompanied by poor cycle stabilities. Here, we report the exploration of robust high-temperature PIBs enabled by a carboxyl functional group energy storage mechanism, which is based on an example of p-phthalic acid (PTA) with two carboxyl functional groups as the redox centers. In such a case, the intercalation/de-intercalation of K+ can be performed via surface reactions with relieved volume change, thus favoring excellent cycle stability for PIBs against high temperatures. As proof of concept, at the fixed working temperature of 62.5 °C, the initial discharge and charge specific capacities of the PTA electrode are ∼660 and 165 mA⋅h⋅g−1, respectively, at a current density of 100 mA⋅g−1, with 86% specific capacity retention after 160 cycles. Meanwhile, it delivers 81.5% specific capacity retention after 390 cycles under a high current density of 500 mA⋅g−1. The cycle stabilities achieved under both low and high current densities are the best among those of high-temperature PIBs reported previously.

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Synthesis, Characterization and Alpha Glucosidase Inhibition activity of new Phthalimide Derivatives

Iraqi Journal of Pharmaceutical Sciences ( P-ISSN 1683 - 3597 E-ISSN 2521 - 3512) ◽

10.31351/vol27iss1pp100-108 ◽

2018 ◽

Vol 27 (1) ◽

pp. 100-108

Author(s):

Hassan ALi ◽

Mohammed H. Mohammed ◽

Sajida H. Ismeal

Keyword(s):

Saccharomyces Cerevisiae ◽

Phthalic Anhydride ◽

Inhibitory Activity ◽

Functional Group ◽

Aliphatic Amine ◽

Inhibition Activity ◽

End Products ◽

Ic50 Values ◽

Carboxyl Functional Group ◽

Alpha Glucosidase

Three of imide intermediate products were synthesized by reacting of phthalic anhydride with glycine (2a), and tetrachloro phthalic anhydride with glycine , (S)-2-[(tert-Butoxycarbonyl)amino]-3-aminopropionic acid ( 2b,c) respectively in dry toluene with azeotropic removal of water using Dean- stark apparatus then carboxyl functional group activated by refluxing with thionyl chloride, the resulted acid chloride (3a-c) were reacted with different amine (5-flourouracil, 4-chloroaniline, 4-bromoaniline, 2-amino thiazole, and pyrrolidine) (4a-e) , the resulted products consider as the end products (5a-j) while the compounds (5k-o) required further reaction to deprotect aliphatic amine this achieved by treating the compounds with TFA to remove tert-Butoxycarbonyl group (6a-e). The alpha glucosidase inhibitory activity of some synthesized compounds (5a, 5f, 6a) were tested by using -glucosidase from Saccharomyces cerevisiae, p-nitrophenol glucopyranoside (pNPG) used as substrate and acarbose used as standard. All these test compounds shows excellent inhibitory activity according to IC50 values which is ranging from (4.61-7.32).

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