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7/6/2012 11:49:36 AM Aravamudhan: Chiral Recognition by NMR 1 Distiguishing features for Chirality Such small chiral molecules are complexed with larger host molecules and the NMR spectra of the resulting complex is used for recognizing the chiral form, the R or S. Amino acids are designated by L or D optical isomers (equivalent to R,S designation) that corresponds to the presence of asymmetric carbon / a chiral centre. Most of them experimental studies and not much Computational chemistry is reported on such systems for the calculation of chemical shifts of un complexed host and ligand, for a comparison with the complexes. Thus this presentation is a study reporting a small molecule docking with a larger molecule and the use of calculation of chemical shifts on certain model systems. Just as much as experimentalists use NMR spectroscopy as an analytical tool for structure determination, it is being pointed out that trends using Chemical shift calculations can be so much useful in modeling studies even if the calculated shift values do not reproduce the experimental shift values.

Distiguishing features for Chirality

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Distiguishing features for Chirality. Such small chiral molecules are complexed with larger host molecules and the NMR spectra of the resulting complex is used for recognizing the chiral form, the R or S. - PowerPoint PPT Presentation

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Page 1: Distiguishing features for Chirality

7/6/2012 11:49:36 AM Aravamudhan: Chiral Recognition by NMR 1

Distiguishing features for ChiralitySuch small chiral molecules are complexed with larger host molecules and the NMR spectra of the resulting complex is used for recognizing the chiral form, the R or S.

Amino acids are designated by L or D optical isomers (equivalent to R,S designation) that corresponds to the presence of asymmetric carbon / a chiral centre.

Most of them experimental studies and not much Computational chemistry is reported on such systems for the calculation of chemical shifts of un complexed host and ligand, for a comparison with the complexes.

Thus this presentation is a study reporting a small molecule docking with a larger molecule and the use of calculation of chemical shifts on certain model systems.

Just as much as experimentalists use NMR spectroscopy as an analytical tool for structure determination, it is being pointed out that trends using Chemical shift calculations can be so much useful in modeling studies even if the calculated shift values do not reproduce the experimental shift values.

Page 2: Distiguishing features for Chirality

The JPG Image

The Full publication by Koylu et al

This docked complex does indicate that a Theoretical Calculation would entail the complications of docking studies in the macromolecular regime (the hyperlinks should display the AGL files and the

corresponding exported images). Thus such a supra molecule studies could derive benefit by modeling with small molecules for favorable features to know the specifics which can then be integrated into a set of conditions for a tangible study of the large molecule. This indication for the necessity for a modeling was pursued to gain some insight; and, the full comprehension of the actualities (regarding the Chiral Recognition by NMR using theoretical methods) would require several compilations of the type presented now, and in the remaining parts.Hyperlink-1 Hyperlink-2

Aravamudhan: Chiral Recognition by NMR 27/6/2012 11:49:36 AM

CPUtime-CalcNMRchemShifts.JPG

Page 3: Distiguishing features for Chirality

Variation of NMR spetrum with Concentration of guest

Increasing amount of Guest molecule

The Full publication by Koylu et al

The Full publication by Koylu et al

The Full publication by Koylu et al

8/9/2012 10:22AM 3S.Aravamudhan CRNMR

Return to Slide#2

Page 4: Distiguishing features for Chirality

8/9/2012 10:22AM S.Aravamudhan CRNMR 4

Deleting the Guest molecule from the complex & Calculating NMR

Webmo Jobs links:107509 107510107511 107512

From these results it is evident that the popularly used Crown Ether system is too large for computational investigations

Page 5: Distiguishing features for Chirality

Thursday, April 20, 2023 S.Aravamudhan ICETCS, CUG March 14-15,2013 5

Questions ; Comments ; Remarks Prof.S.Aravamudhan Phone:0364 272 2615Department of Chemistry Mobile: 9862053872North Eastern Hill University Email: [email protected]

Shillong 793003 Meghalaya URL: http://aravamudhan-s.ucoz.com

A link to the facsimile of the participation certificate