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Information card for entry 2006749
Preview
| Coordinates | 2006749.cif |
|---|---|
| Original IUCr paper | HTML |
| External links | ChemSpider; PubChem |
| Chemical name | 2-methyl-5,8-dioxo-5,8-dihydro-furo[3,2-g]chromone |
|---|---|
| Formula | C12 H6 O5 |
| Calculated formula | C12 H6 O5 |
| SMILES | c1(cc(=O)c2c(C(=O)c3c(C2=O)cco3)o1)C |
| Title of publication | The Khellin Quinone |
| Authors of publication | Yakoubi, Abderrahman; Jalel Eddine Hila; Habib, Boughzala; Bizid, Abdelmalek |
| Journal of publication | Acta Crystallographica Section C |
| Year of publication | 1997 |
| Journal volume | 53 |
| Journal issue | 12 |
| Pages of publication | 1949 - 1950 |
| a | 7.552 ± 0.003 Å |
| b | 8.172 ± 0.001 Å |
| c | 15.624 ± 0.003 Å |
| α | 90° |
| β | 99.29 ± 0.02° |
| γ | 90° |
| Cell volume | 951.6 ± 0.4 Å3 |
| Cell temperature | 293 ± 2 K |
| Ambient diffraction temperature | 293 ± 2 K |
| Number of distinct elements | 3 |
| Space group number | 14 |
| Hermann-Mauguin space group symbol | P 1 21/c 1 |
| Hall space group symbol | -P 2ybc |
| Residual factor for all reflections | 0.0799 |
| Residual factor for significantly intense reflections | 0.0464 |
| Weighted residual factors for all reflections | 0.1205 |
| Weighted residual factors for significantly intense reflections | 0.1035 |
| Goodness-of-fit parameter for all reflections | 1.093 |
| Goodness-of-fit parameter for significantly intense reflections | 1.19 |
| Diffraction radiation wavelength | 0.71069 Å |
| Diffraction radiation type | MoKα |
| Has coordinates | Yes |
| Has disorder | No |
| Has Fobs | No |
| Revision | Date | Message | Files |
|---|---|---|---|
| 301791 (current) | 2025-08-19 | Add cross-references to PubChem compounds in COD range 2/00 Each referenced PubChem compound corresponds to the full crystal structure. |
2006749.cif |
| 201955 | 2017-10-13 | cif/2/ Marking COD entries in range 2/00 that are known to be related to ChemSpider entries using the _cod_related_entry data loop. |
2006749.cif |
| 176759 | 2016-02-19 | cif/2/ (antanas@echidna.ibt.lt) Replacing _[local]_cod_* tags with their equivalents from the COD CIF dictionary in multiple entries in subrange 2/00. |
2006749.cif |
| 171462 | 2015-12-13 | cif/ (antanas@echidna.ibt.lt) Removing surrounding qoutes ("'") from the _chemical_name_systematic tag values in multiple entries in range 2. |
2006749.cif |
| 134621 | 2015-04-02 | The 'cif_fix_values' script with an option '--fix-only-weighting-scheme' and 'cif_filter' script were run over CIF files which included an incorrect value of the data item '_refine_ls_weighting_scheme'. Read the log for more details. There were more than 18k CIF files with values to modify. Usually these incorrect values include comment with formulas, but values of this data item must be an enumerator. The script creates new data item '_refine_ls_weighting_details' to store these comments with formulas, and writes the enumerator 'calc' as a value of data item '_refine_ls_weighting_scheme'. There exists some exceptions in the script. |
2006749.cif |
| 130086 | 2015-01-23 | cod/ (robertas@burundukas) The 'cif_fix_values' program was applied to CIFs that have generated the validation messages containing tag '_exptl_crystal_density_meas'. 16946 CIFs had a values that were perceived as 'not measured' and they were changed to '?'. The total of 17089 CIFs was changed. Those that were not corrected by 'cif_fix_values' were reformatted by the parser (e.g. a doi tag was moved to another place). The processing command was: mysql -u cod_reader -h www.crystallography.net cod -e \ 'select distinct codid from validation \ where message like \ "%tag%_exptl_crystal_density_meas'\''%"' -NB \ | xargs -i sh -c 'cif_fix_values {} \ | cif_filter --add-cif-header {} \ | sponge {}' |
2006749.cif |
| 91933 | 2013-12-28 | cif/ (saulius@koala.ibt.lt) Adding DOIs that could be assigned unambiguously to the range 2x CIFs. |
2006749.cif |
| 32112 | 2012-02-03 | cif/: committing an update of 45+ thous files, with information appended from the originals. | 2006749.cif |
| 26848 | 2011-09-28 | cif/2/, hkl/2/, html/ Reorganising CIFs of the range 2* into the "prefix-directory" tree. |
2006749.cif |
| 26029 | 2011-09-17 | cif/2/ Reverting changes of revision 25271: ( cd cif/2/; svn merge -r25271:25270 . ) The problem was that the reprocessed files from IUCr, although were more complete, "resurrected" data errors that were corrected in the previous recisions. The additional data that have been extracted during the reprocessing will have to be merged without overwriting the existing values in COD files, except some explicit and controlled cases (such as publication titles and chemical names). |
2006749.cif |
| 25271 | 2011-09-10 | cif/2/ Adding reporocessed IUCr CIFs for the years 1980-2010. The CIFs now contain more complete bibliography, substance names, correctly unfolded text fields (using the CIF line unfolding protocol), explicitely set cell angles, and _cod_data_source_block fields. |
2006749.cif |
| 966 | 2010-01-30 | cif/ Adding _cod_database_code tags to all COD entries. Adding tag description to the cif_cod.dic dictionary so that COD entries can be validated. |
2006749.cif |
| 853 | 2009-11-16 | cif/ Reconstructing spacegroup designators from the symmetry operators were possible. The comands used can be found in the log file reformat-spacegroups-2009.11.14.log committed with the current revision. Only lines that contained spacegroup designators were changed, and all files pass vcif test after the conversion. |
2006749.cif |
| 481 | 2008-11-20 | Changing volume number in numerous Acta Cryst. C published CIFs from 'C[0-9]?[0-9]' into '[0-9]?[0-9]'. This makes the COD CIF collection more uniform, and also helps the deposition scripts to spot potential duplicates more accurately. The command for this transformation was: for i in 2/*.cif; \ do ( \ if grep -q '_journal_volume *C' $i && \ grep -q '_journal_name_full .*Acta *Cryst' $i; \ then \ echo === $i ===; \ perl -i -pe 's/_journal_volume *C/_journal_volume /' $i; \ perl -i -pe \ "s/_journal_name_full .*/_journal_name_full 'Acta Crystallographica Section C'/" $i ; \ fi \ ) done |
2006749.cif |
| 19 | 2008-01-26 | Changing all end-of-line codes from DOS style to UNIX style in all COD CIF files, for more convenient processing: In the cod/cif/ directory: ff \*.cif | xargs perl -i -pe 's/\r\n/\n/' |
2006749.cif |
| 14 | 2008-01-14 | Appending a header with SVN keywords, COD URL and copying policy to all COD CIF files. |
2006749.cif |
| 13 | 2008-01-13 | Setting the svn:keywords property to "Author Date Revision URL Id" for all CIF files in the cod/cif directory. |
2006749.cif |
| 1 | 2007-11-30 | Adding all .cif files from the COD, downloaded in a Cod.zip file on 2007.02.07 (and the same Cod.zip is downloadable today, on 2007.11.29) |
2006749.cif |
All data in the COD and the database itself are dedicated to the
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Users of the data should acknowledge the original authors of the
structural data.