Chords, Version 2.0
CHORDS
Interactive Graphical Simulation of Spectral Data
CHORDS 1 (Coherent HOmonucleaR spin Dynamics Simulation)
- CHORDS provides an interactive graphical comparison of spectral simulation.
- Simulates homonuclear J-correlated spectra of weakly and strongly coupled spins, and takes into consideration the experimental acquisition and processing parameters.
- Imports a variety of vendor formats (Bruker, Varian, JEOL, Felix, Triad, NMR-Compass).
- Provides the ability to simulate severly overlapped cross peaks by handling several spin systems simultaneously.
- Performs fast simulations on either complete or partial regions of the spectrum.
- Provides an interactive graphical interface to vary the coupling constants (J) of the spin systems and monitor the simulated spectra.
- Allows for spectral simulation and comparison with experimental data for assisting NMR assignment of Protein, DNA and other natural products.
J-value and Experiment Palettes
Peaks Table from CHORDS
| File | Identifier | X Point | Y Point | X PPM | Y PPM | Intensity |
| Exp | 1 | 3 | 7 | 4.900 | 3.630 | +172133.78 |
| Exp | 2 | 3 | 11 | 4.900 | 3.650 | -201444.23 |
| Exp | 3 | 6 | 8 | 4.915 | 3.635 | +414173.22 |
| Exp | 4 | 6 | 11 | 4.915 | 3.650 | -454572.16 |
| Exp | 5 | 11 | 7 | 4.940 | 3.630 | -397608.03 |
| Exp | 6 | 11 | 11 | 4.940 | 3.650 | +443639.66 |
| Exp | 7 | 12 | 15 | 4.945 | 3.670 | -104149.22 |
| Exp | 8 | 14 | 8 | 4.955 | 3.635 | -144950.03 |
| Exp | 9 | 14 | 11 | 4.955 | 3.650 | +176156.02 |
| Exp | 10 | 16 | 11 | 4.965 | 3.650 | -103079.99 |
Applications
- Spectral simulation and comparison with experimental data for assisting NMR assignment of Protein, DNA and other natural products data.
- Measurement of J-coupling constants.
Academic Origin
CHORDS has been developed by Drs. R. Ajay Kumar and A. Majumdar in the laboratories of Profs. Hosur and Govil at the TATA Institute of Fundamental Research, India. Portions of CHORDS are copyright 1990 through 1994 TATA Institute of Fundamental Research, India, and are exclusively licensed to Spectrum Research, LLC. Title and full ownership rights to the converted/modified CHORDS remain solely with Spectrum Research, LLC. and CHORDS is asserted to be Spectrum's proprietary information and trade secret.
Hardware Requirements
- Silicon Graphics workstations (Irix 5.x & 6.x)
- Sun Workstations (Solaris 2.5 & above)
- Windows NT 4.0 and above & Windows 95/98/2000.
Click here to download a free, trial version of CHORDS
CHORDS References
- Kumar, R. A.; Majumdar, A.; Memorial Sloan-Kettering Cancer Center, New York, NY; Coherent Homonuclear Spin Dynamics Simulation: CHORDS; The 36th ENC Conference, March 26-30, 1995, Boston, MA.
- Majumdar, A. & Hosur, R. V., Prog. NMR Spec 24, 109-158 (1992).
- Cosman, M, Fiala, R, Hingerty, BE, Amin, S, Geacintov, NE, Broyde, S, and Patel, DJ. Solution conformation of (+)-trans-anti-[BP]dG adduct opposite a deletion site in a DNA duplex: intercalation of the covalently attached benzo[a]pyrene into the helix with base displacement of the modified deoxyguanosine into the major groove. Biochemistry, 33:11507-17(94).
- Cosman, M, Fiala, R, Hingerty, BE, Amin, S, Geacintov, NE, Broyde, S, and Patel, DJ. Biochemistry, 33:11518-27(94).
- Cosman, M, Fiala, R, Hingerty, BE, Laryea, A, Amin, S, Geacintov, NE, Broyde, S, and Patel, DJ. Biochemistry, 34:1295-1307(95).
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