NMR spectral database system

The assignment of the monomer solution spectrum was performed by using an NMR spectral database system (SDBS-NMR)54. The signals of the six acetylene carbons from 60.34 to 81.91 ppm in the solution spectrum indicated the monomer structure of a dodec-ahexyne derivative substituted symmetrically by alkyl groups. Since the spectral patterns in Figure 36A are almost the same as those of the monomer, only a small extent of polymerization had occurred during the 30 min after recrystallization. The signal at about... 

The assignment of the monomer solution spectrum was performed by using an NMR spectral database system (SDBS-NMR). The signals of the six acetylene carbons from... 

The National Chemical Laboratory for Industry (NCLl), Japan, has developed an integrated Spectral Database System (SDBS) which is available to users in Japan. AU spectra were deterrnined at NCLl under controUed conditions and are available on a PC/CD-ROM or magnetic tape. The system has both H-nmr (6000 compounds) and C-nmr spectra (5700 compounds), along with searching software. NCLl has also developed an integrated C— H-nmr system that can be used for two-dimensional data elucidation (70,71). 

Figure 5.9. Spectral search at Spectral Database Systems (SDBS). The infrared (IR), nuclear magnetic resonance H-NMR and 13C-NMR), electron spin resonance (ESR), and mass (MS) spectra of organic compounds and common biochemical compounds can be viewed/retrieved from SDBS.

Figure 5.10. Sample spectra retrieval from SDBS. (a) 13C-NMR spectrum in DMSO-d6. (b) -NMR (400 MHz) spectrum in DMSO-d6. (c) Mass spectrum, (d) Infrared spectrum in KBr. Sample spectra (including spectral analysis) of uracil are retrieved from Spectral Database Systems. The structure of uracil (molecular weight = 112) is represented with the number corresponding to the position of carbons and the alphabet denoting the position of protons to facilitate NMR assignments ...

A number of NMR spectral databases exist to aid the natural product chemist in structure elucidation. Speclnfo currently contains 359000 13C NMR spectra and 130 000 3H NMR assigned spectra.106 CSearch is another repository with a number of data sets.107 Both Speclnfo and CSearch provide structure prediction based on the database content. NMRShiftDB is an open access, open submission NMR web database for structures and their NMR spectra. It allows users to predict spectra and search for spectra and structures.108,109 NMRPredict is offered with MestReNova and predicts ll and 13C spectra from a structure.110 The Madison Metabolomics Consortium Database (MMCD http //mmcd.nmrfam.wisc.edu/) is a web-based bioinformatics resource that contains experimental NMR data on 447 compounds.111 Additionally, the system contains information on more than 20 000 small molecules and can be queried using text, structure, NMR, mass and miscellanea.111,112 ChemGate allows users to search for NMR data by structures or substructures and also predicts NMR spectra.113... 

Integrated Spectral DataBase System for Organic Compounds, National Institute of Materials and Chemical Research, Tsukuba, Ibaraki 305-8565, Japan. This database includes infrared, mass spectra, and NMR data (proton and carbon-13) for a number of compounds. 

Peter Lundberg, University of Umea, Sweden, has compiled a very complete list of educational NMR software. It is available from a number of sites, including http //atlas.chemistry.uakron.edu 8080/cdept.docs/ MAGNET/sware.html and the Bruker Web sites. http //www.aist.go.jp/RIODB/SDBS/menu-e.html Integrated Spectral DataBase System for Organic Compounds, National Institute of Materials and Chemical Research, Tsukuba, Ibaraki 305-8565, Japan. This database includes infrared, mass spectra, and NMR data (proton and carbon-13) for a number of compounds. http //www. chem. ucla. edu/ webnmr/... 

National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan, publishes a free spectral database system for organic compounds. The spectra include IR, Raman, NMR, and MS for most compounds. The database may be accessed at www.aist.go.jp/RIODB/SDBS. 

In addition to the intensity, other properties such as polarization are concerned in optical rotatory dispersion and circular dichroism. The various processes give rise to different spectroscopic methods, as summarized in the Table 7.1. Various spectra (UV, IR, NMR and MS) of simple biomolecules can be accessed from Spectral Database Systems (SDBS) of the National Institute of Material and Chemical Research, Japan at http //www.sist.go.jp/RIODB/SDBS/menu-e.html. 

Spectral Database for Organic Compounds (SDBS) is an integrated spectral database system for organic compounds, which includes six different types of spectra, an electron-impact mass spectrum (EI-MS), a Fourier transform infrared spectrum (FT-IR), a H NMR spectrum, a NMR spectrum, a laser Raman spectrum, and an electron spin resonance (ESR) spectrum [72], SDBS is maintained by the National Metrology Institute of Japan (NMU) under the National Instimte of Advanced Industrial Science and technology (AIST). Currently, EI-MS spectrum, H NMR spectrum, C NMR spectrum, FT-IR spectrum, and the compound dictionary are... 

Bio-Rad Laboratories, Informatics Division, Philadelphia, PA (www.bio-rad.com), publishes the Sadtler IR and Raman spectra collections of over 240,000 spectra. They are available in electronic format and in a variety of specialized subsets, including ATR-IR, with collections of controlled and prescription drugs, nutraceuticals, forensics, polymers, and more. Sigma-Aldrich Chemical Company (www.sigma-aldrich.com) publishes over 18,000 FTIR spectra. National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan, publishes a free spectral database system of organic compounds. The spectra include IR, Raman, NMR, and MS for most compounds. The database may be found at www.aist.go.jp/RIODB/SDBS. 

There are two kinds of computer-aided structure elucidation methods logic-oriented and database-oriented approaches. The computer program systems adopted for either approach require a high quality spectral database. The authors have been constructing proton and carbon-13 NMR spectral databases applicable to the computer systems for both approaches for more than 10 years. ... 

Raman, and nmr spectra. An extensive bibliography of older hard-copy ir spectra is given in The Coblent Sodety Desk Book of Infrared Spectra (62). Since the mid-1980s, comprehensive databases have been available in computerized form where the spectra themselves, not merely the bibliographic references, are searchable and displayable. The search algorithms vary considerably among the available systems no algorithm standard exists (ca 1994), but several are under development (63,64). Expert systems, which assist in the automatic interpretation and identification of spectra, have existed for many years but are not commonly used (65). Computerized spectral databases are either local, PC-based, or public. 

The major bottleneck created by these high-throughput NMR techniques is in the analysis of the vast amount of data that is generated. A number of commercial packages are now available that use chemical shift/structure databases to aid in the interpretation of the spectra. However, fully automated spectral analysis systems are still under development. 

The spectral signals are assigned to the HOSE codes that represent the corresponding carbon atom. This approach has been used to create algorithms that allow the automatic creation of "substructure-sub-spectrum databases that are now used in systems for predicting chemical structures directly from NMR. 

Miscellaneous. NIST has a reference database of criticaUy evaluated x-ray photoelectron and Auger spectral data, which is designed to mn on PCs. It is searchable by spectral lines as weU as by element, line energy, and chemical data (82). The Nuclear Quadrapole Resonance Spectra Database at Osaka University of over 10,000 records is avaUable in an MS-DOS version (83). The NCLl system, SDBS, has esr and Raman spectra, along with nmr, ir, and ms data, as described. 

Spectra. The ability to consult collections of standard spectra is crucial in the analysis of unknown compounds A long history of data collection efforts has been aimed at these applications. Among ihe best known of the published handbooks arc the Sadtlcr Spectral Data Sheets, which include ir. Raman, and nmr spectra. On-line sources include the Chemical Information System. Speclnlo. and The Canadian Scientific Numeric Database Service tCAN/SND). 

Finally, for routine applications, our software provides a database management system called BASIS for storage and manipulation of chemical information. BASIS can access generally available spectral libraries from three different spectroscopic techniques (MS, H-NMR and F13C-NMR, IR), and permits the creation of new libraries. For structure elucidation and substructure search of unknown compounds, library search algorithms allow the retrieval of identical and structurally similar spectra. 

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