Conformational analysis of 5-H-dibenzo[a,d]cycloheptene derivatives with flexible amino-substituted side-chains by means of lanthanide induced shifts (LIS). Conformational analysis of highly flexible structures, part III

1992 ◽  
Vol 123 (11) ◽  
pp. 1045-1058 ◽  
Author(s):  
Otmar Hofer ◽  
Walter Weissensteiner
Keyword(s):  
Conformational Analysis ◽  
Flexible Structures ◽  
Side Chains ◽  
Lanthanide Induced Shifts

The solution structure of lidocaine: Conformational analysis and NMR lanthanide-induced shifts

1985 ◽  
Vol 23 (11) ◽  
pp. 945-951 ◽  
Author(s):  
Laurine A. Laplanche ◽  
Garret Vanderkooi ◽  
Halila Jasmani ◽  
Maimunah Mat Suki
Keyword(s):  
Conformational Analysis ◽  
Solution Structure ◽  
Lanthanide Induced Shifts

Synthesis ofL-threo- andL-erythro-[1-13C, 2,3-2H2]amino acids: novel probes for conformational analysis of peptide side chains

1995 ◽  
pp. 1603-1609 ◽  
Author(s):  
Makoto Oba ◽  
Ryuichi Ueno ◽  
Mika Fukuoka (née Yoshida) ◽  
Masatsune Kainosho ◽  
Kozaburo Nishiyama
Keyword(s):  
Amino Acids ◽  
Conformational Analysis ◽  
Side Chains

scholarly journals Conformational Analysis of the Oligosaccharides Related to Side Chains of Holothurian Fucosylated Chondroitin Sulfates

Marine Drugs ◽  
2015 ◽  
Vol 13 (2) ◽  
pp. 936-947 ◽  
Author(s):  
Alexey Gerbst ◽  
Andrey Dmitrenok ◽  
Nadezhda Ustyuzhanina ◽  
Nikolay Nifantiev
Keyword(s):  
Conformational Analysis ◽  
Side Chains ◽  
Chondroitin Sulfates

Effects of side chains in gas-phase amino acids: Conformational analysis and relative stabilities

2009 ◽  
Vol 901 (1-3) ◽  
pp. 81-87 ◽  
Author(s):  
Gang Yang ◽  
Lijun Zhou ◽  
Yuangang Zu ◽  
Yujie Fu ◽  
Rongxiu Zhu ◽  
...  
Keyword(s):  
Amino Acids ◽  
Conformational Analysis ◽  
Gas Phase ◽  
Side Chains ◽  
Relative Stabilities

scholarly journals MICE-PES: An Algorithm for Accurate Conformational Analysis and its Implementation to Natural Products

2021 ◽  
Author(s):  
◽  
Muhammad Ali Hashmi
Keyword(s):  
Conformational Analysis ◽  
Degrees Of Freedom ◽  
Force Fields ◽  
Flexible Structures ◽  
Chemical Properties ◽  
General Purpose ◽  
Field Methods ◽  
Relative Configuration ◽  
Incremental Construction

<p>Secondary metabolites from natural sources have revolutionized the modern drug industry by acting as lead compounds. Many commercial drugs have evolved originally from natural molecules before being synthesized in the laboratory for commercialization. Because of the importance of natural molecules, it is crucial to determine their structural properties carefully as it is essential for their synthesis and studying their pharmacological behaviour. Many natural molecules have flexible structures and can adopt many different conformations in solution at room temperature. Hence, the determination of their relative configuration is a challenging task with the available experimental techniques. For structural analysis of natural molecules and to study their properties, all conformers which might be responsible for their chemical properties have to be considered.  Theoretical chemistry has been very helpful in absolute structure determination of complex and conformationally flexible natural molecules by calculating their theoretical nuclear magnetic resonance, ultraviolet, infra red, and circular dichroism spectra etc. There are a number of software tools that offer conformational analysis by utilizing different molecular mechanics approaches. They produce a large number of possible conformers and are not general purpose, thus compromising accuracy. Apart from that, different force fields available for conformational analysis and minimization have been designed for specific molecular classes and do not produce good results beyond their scope.  In the past, there have been reports about a “build-up procedure” for predicting the low energy conformations of peptides by optimising smaller fragments of the molecule under study and then joining them while minimizing their energies using force fields. Later on, this method was extended to predict the structure of DNA from sequences. This method used force field methods and did not gain much popularity due to its various limitations.  Here, MICE-PES (Method for the Incremental Construction and Exploration of the Potential Energy Surface) is presented, an algorithm which performs a conformational analysis using high level quantum chemical calculations by building the molecule incrementally from its smallest possible analogue whose conformational degrees of freedom are very well separated than the rest of the molecule. MICE-PES has been validated through studies on known biomolecule 3-epi-xestoaminol whose absolute configuration has been determined already by experimental and theoretical methods. MICE-PES has also been used to assign the relative configuration of a natural product (meroterphenol C) whose configuration could not be established experimentally. Overall, the development of MICE-PES will be very helpful in solving problems in the study of conformationally flexible systems, in all aspects of organic chemistry.</p>

Sign in / Sign up

Export Citation Format

Share Document