THEORETICAL ANALYSIS OF THE STRUCTURE AND VIBRATIONAL SPECTR OF ASPARAGINE AND GLUTAMIC AMINO ACIDS IN WATER AT DIFFERENT pH

The objective of this investigation was to develop two cyclobutadiene-steroid derivatives (compounds 6 or 7) to evaluate its theoretical interaction on µ, d, and k opioid-receptors. The synthesis of 6 or 7 was carried out using a series of reactions which involves. 1) addition/cyclization: 2) imination, 3) etherification and 4) oxy-functionalization. Chemical structure of all compounds was confirmed using elemental analysis and NMR spectra. In addition, a theoretical analysis on the interaction of compounds 6 or 7 with µ, d, and k opioid-receptors was evaluated using a docking model. The results showed that 6 or 7 may interact with different type of amino acids residues on surface of the µ, d, and k opioid-receptors. Other data, indicated that inhibition constant (Ki) involved in the interaction of compounds 6 or 7 with k receptor was less compared with the Ki present in the interaction with µ, d, receptors. These data indicated that 1) compounds 6 or 7 show a high affinity by k-receptor; 2) the cyclobutadiene analogs are particularly interesting, because these drugs may constitute a novel therapy for pain.

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Theoretical analysis of apical bonding in copper(II) chelates withN-substituted amino acids

Journal of Applied Crystallography ◽

10.1107/s0021889809047748 ◽

2009 ◽

Vol 43 (1) ◽

pp. 42-47 ◽

Cited By ~ 1

Author(s):

Ante Miličević ◽

Nenad Raos

Keyword(s):

Amino Acids ◽

Theoretical Analysis ◽

Bond Length ◽

Coordination Polyhedron ◽

Naturally Occurring ◽

Steric Crowding ◽

Overlapping Spheres

The interdependence between the side of apical coordination of H2O and steric crowding at the apical positions was investigated on a set of 34 copper(II) bis-complexes withN- andN,N-substituted amino acids. As a measure of steric crowding, overlapping volumesV* were used, calculated using a modified overlapping spheres method. Steric crowding around the apically bonded ligand was the same for this set of complexes as for the copper(II) bis-complexes with naturally occurring amino acids, with the optimal occupied volume values between 1 and 1.5 Å3. The interdependence between the length of the apical bond and distortion of the coordination polyhedron was also studied. The apical bond length showed sigmoidal dependence on the magnitude of distortion.

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Synthesis of β-lactams and cyclo-β-dipeptides from β-amino acids: experimental observations and theoretical analysis

Tetrahedron ◽

10.1016/s0040-4020(00)01169-8 ◽

2001 ◽

Vol 57 (10) ◽

pp. 1883-1890 ◽

Cited By ~ 30

Author(s):

Jaime Escalante ◽

Miguel A González-Tototzin ◽

Judit Aviña ◽

Omar Muñoz-Muñiz ◽

Eusebio Juaristi

Keyword(s):

Amino Acids ◽

Theoretical Analysis

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Chiral Phonons in Biocrystals

10.21203/rs.3.rs-248321/v1 ◽

2021 ◽

Author(s):

Won Jin Choi ◽

Keiichi Yano ◽

Minjeong Cha ◽

Felippe Colombari ◽

Yichun Wang ◽

...

Keyword(s):

Experimental Data ◽

Amino Acids ◽

Theoretical Analysis ◽

Lattice Vibrations ◽

Structure Property ◽

Spectral Signatures ◽

Structure Property Relationships ◽

Left And Right ◽

Collective Vibrations ◽

Chiroptical Spectroscopy

Abstract Chiral phonons are concerted mirror-symmetric movements of atomic groups connected by covalent and intermolecular bonds. Finding chiral phonons in biocrystals is fundamentally and technologically important because these lattice vibrations should be highly specific to their short- and long-range organizations. Based on theoretical and experimental data they might be expected but not identified or utilized. Here we show that terahertz chiroptical spectroscopy enables registration and attribution of chiral phonons in microcrystals of numerous amino acids and dipeptides. Theoretical analysis and computer simulations confirm that sharp mirror-symmetric bands observed for left and right enantiomers originate from collective vibrations of biomolecules interconnected by hydrogen bonds into helical chains. Structure-property relationships for strong phonons with rotatory components in biocrystals were also identified. Bladder stones and health supplements display strong spectral signatures of chiral phonons indicating their immediate importance for biomedicine.

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Theoretical analysis of apical bonding in copper(II) chelates with amino acids

Journal of Applied Crystallography ◽

10.1107/s0021889809023589 ◽

2009 ◽

Vol 42 (5) ◽

pp. 793-797 ◽

Cited By ~ 1

Author(s):

Ante Miličević ◽

Nenad Raos

Keyword(s):

Amino Acids ◽

Theoretical Analysis ◽

Bond Length ◽

Dimethyl Sulfoxide ◽

Coordination Polyhedron ◽

Side Chain ◽

Naturally Occurring ◽

Steric Crowding ◽

Overlapping Spheres

The interdependence between the side of apical coordination (H2O, >C=O, dimethyl sulfoxide and Cl−) and steric crowding at the apical positions was investigated for a set of 20 copper(II) bis complexes with naturally occurring amino acids. As a measure of steric crowding the overlapping volumes,V*, were used, calculated by the modified overlapping spheres method. It was found that the apically coordinated side of a complex is more hindered by the side-chain atoms. In addition, if both sides are apically coordinated, the apical bond is shorter at the more crowded side. The interdependence between the length of the apical bond and distortion of the coordination polyhedron was also studied. The apical bond length shows sigmoidal dependence on the magnitude of distortion, and is also dependent on the kind of distortion (square-pyramidal or tetrahedral).

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Li@C60 complexes with amino acids: A theoretical analysis

Journal of Organometallic Chemistry ◽

10.1016/j.jorganchem.2008.01.008 ◽

2008 ◽

Vol 693 (6) ◽

pp. 1143-1149 ◽

Cited By ~ 13

Author(s):

Abraham F. Jalbout

Keyword(s):

Amino Acids ◽

Theoretical Analysis

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Homochirality as the Signature of Extra-Terrestrial Life

International Astronomical Union Colloquium ◽

10.1017/s0252921100015037 ◽

1997 ◽

Vol 161 ◽

pp. 505-510

Author(s):

Alexandra J. MacDermott ◽

Laurence D. Barron ◽

Andrè Brack ◽

Thomas Buhse ◽

John R. Cronin ◽

...

Keyword(s):

Amino Acids ◽

Protein Synthesis ◽

Optical Rotation ◽

Physical Origin ◽

Natural Choice ◽

Rosetta Mission ◽

Terrestrial Life ◽

Subsurface Layers ◽

Solar System Bodies ◽

Origin Of Homochirality

AbstractThe most characteristic hallmark of life is its homochirality: all biomolecules are usually of one hand, e.g. on Earth life uses only L-amino acids for protein synthesis and not their D mirror images. We therefore suggest that a search for extra-terrestrial life can be approached as a Search for Extra- Terrestrial Homochirality (SETH). The natural choice for a SETH instrument is optical rotation, and we describe a novel miniaturized space polarimeter, called the SETH Cigar, which could be used to detect optical rotation as the homochiral signature of life on other planets. Moving parts are avoided by replacing the normal rotating polarizer by multiple fixed polarizers at different angles as in the eye of the bee. We believe that homochirality may be found in the subsurface layers on Mars as a relic of extinct life, and on other solar system bodies as a sign of advanced pre-biotic chemistry. We discuss the chiral GC-MS planned for the Roland lander of the Rosetta mission to a comet and conclude with theories of the physical origin of homochirality.

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