ChemInform Abstract: Silver-Mediated Direct Amination of Benzoxazoles: Tuning the Amino Group Source from Formamides to Parent Amines.

Aminocoumarins are one of the important core structural systems, present in several biologically and medicinally active compounds. Owing to its natural occurrence, potential pharmacological applications and remarkable versatility as a privileged precursor, several proficient synthetic protocols have been reported in the literature over the past years. The presence of an amino group and enamine carbon enhances its chemical reactivity and thus such functionality is repeatedly used for the construction of various fused and simple heterocycles. This review highlights the preparation of different aminocoumarins and their applications for the construction of a variety of five, six and eight membered fused heterocycles.

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Substituent Effects on the Basicity of ortho-, meta- and para-substituted N1,N1-Dimethyl-N2-phenylformamidines in Ethanol and in Water

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19920113 ◽

1992 ◽

Vol 57 (1) ◽

pp. 113-118

Author(s):

Ewa Daniela Raczyńska

Keyword(s):

Quantitative Analysis ◽

Aqueous Ethanol ◽

Substituent Effects ◽

Amino Group

The relative δpKa values of ortho-, meta-, and para-substituted N1,N1-dimethyl-N2-phenylformamidines obtained in 95.6% aqueous ethanol have been compared with those in water. The comparison shows only some differences in the ortho substituent effects. The meta and para substituent effects in ethanol are not very different from those in water. Quantitative analysis of the experimental δpKa values based on the Taft equation has led to separation of the total electromeric effects into the inductive and mesomeric effects. As compared to the amino group in anilines, the formamidine group is more sensitive to the transmission of the inductive than the mesomeric effects.

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Semisynthesis of peptides - New strategy for specific protection and deprotection of the α-amino group of recombinantly-produced peptide fragments

Collection Symposium Series ◽

10.1135/css199901165 ◽

1999 ◽

Author(s):

Johann M. Brass ◽

Julie Frank ◽

Fred W. Wagner ◽

Hans Stocker ◽

Erich Wünsch

Keyword(s):

Amino Group ◽

Peptide Fragments ◽

New Strategy

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Induced Smectic Phases II. Influence of the Amino Substituent on the Induction of Smectic Phases

Zeitschrift für Naturforschung A ◽

10.1515/zna-1981-1011 ◽

1981 ◽

Vol 36 (10) ◽

pp. 1086-1091 ◽

Cited By ~ 1

Author(s):

F. Schneider ◽

N. K. Sharma

Keyword(s):

Liquid Crystal ◽

Electron Donor ◽

Amino Group ◽

Donor Property ◽

Smectic Phases ◽

Ct Complexes ◽

Induced Smectic Phases

The diagrams of state have been studied for some liquid crystal mixtures which show the induction of smectic phases. Each of the systems studied contains one component with an amino group which influences the polarity and the electron donor property of the molecules. The discussion of the diagrams of state, of the thickness of the smectic layers and of the colours of the mixtures, which indicate the formation of CT complexes, shows that existing models can not explain the induction of smectic phases.

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The site of attachment of retinal in bacteriorhodopsin. The epsilon-amino group in Lys-41 is not required for proton translocation.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)34165-6 ◽

1982 ◽

Vol 257 (15) ◽

pp. 8596-8599 ◽

Cited By ~ 4

Author(s):

K S Huang ◽

M J Liao ◽

C M Gupta ◽

N Royal ◽

K Biemann ◽

...

Keyword(s):

Proton Translocation ◽

Amino Group

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Catalytic Antioxidant Activity of Bis-Aniline-Derived Diselenides as GPx Mimics

Molecules ◽

10.3390/molecules26154446 ◽

2021 ◽

Vol 26 (15) ◽

pp. 4446

Author(s):

Giancarlo V. Botteselle ◽

Welman C. Elias ◽

Luana Bettanin ◽

Rômulo F. S. Canto ◽

Drielly N. O. Salin ◽

...

Keyword(s):

Antioxidant Activity ◽

Hydrogen Bond ◽

Electronic Properties ◽

Partial Charge ◽

Amino Group ◽

Diphenyl Diselenide ◽

Charge Delocalization ◽

Ipso Substitution ◽

Efficient Route ◽

Catalytic Performances

Herein, we describe a simple and efficient route to access aniline-derived diselenides and evaluate their antioxidant/GPx-mimetic properties. The diselenides were obtained in good yields via ipso-substitution/reduction from the readily available 2-nitroaromatic halides (Cl, Br, I). These diselenides present GPx-mimetic properties, showing better antioxidant activity than the standard GPx-mimetic compounds, ebselen and diphenyl diselenide. DFT analysis demonstrated that the electronic properties of the substituents determine the charge delocalization and the partial charge on selenium, which correlate with the catalytic performances. The amino group concurs in the stabilization of the selenolate intermediate through a hydrogen bond with the selenium.

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Water-promoted dehydrative coupling of 2-aminopyridines in heptane via a borrowing hydrogen strategy

RSC Advances ◽

10.1039/d1ra04118e ◽

2021 ◽

Vol 11 (37) ◽

pp. 23144-23150

Author(s):

Taku Nakayama ◽

Hidemasa Hikawa ◽

Shoko Kikkawa ◽

Isao Azumaya

Keyword(s):

Coupling Reaction ◽

Direct Amination ◽

Borrowing Hydrogen ◽

Novel Strategy

We describe a novel strategy for the water-promoted dehydrative coupling reaction in heptane, which offers a sustainable direct amination of alcohols.

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