(IUCr) Crystallography Journals Online checkcif report

[Contents scheme]

Acta Cryst. (2010). E66, o404 [ doi:10.1107/S1600536810001704 ]

1-(1-Carboxymethyl-1,4-anhydro-2,3-O-isopropylidene--D-erythrofuranosyl)thymine

G. M. J. Lenagh-Snow, S. F. Jenkinson, A. J. Stewart, G. W. J. Fleet and D. J. Watkin

Online 20 January 2010

Key indicators

Single-crystal X-ray study
T = 150 K
Mean (C-C) = 0.006 Å
R factor = 0.047
wR factor = 0.114
Data-to-parameter ratio = 7.4

checkCIF/PLATON results

No syntax errors found




Alert level B
PLAT910_ALERT_3_B Missing # of FCF Reflections Below Th(Min) .....         26      

Alert level C
PLAT089_ALERT_3_C Poor Data / Parameter Ratio (Zmax .LT. 18) .....       7.43

Author Response: The crystal is Z'=2 and has a non-centrosymmetric space group. The crystal was small and weak and didn't scatter well at high angle.

PLAT340_ALERT_3_C Low Bond Precision on  C-C Bonds (x 1000) Ang ..          6      
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600         27      
PLAT913_ALERT_3_C Missing # of Very Strong Reflections in FCF ....         13      
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600         21      

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           26.06
           From the CIF: _reflns_number_total               3090
           Count of symmetry unique reflns         3163
           Completeness (_total/calc)             97.69%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present         no
PLAT960_ALERT_3_G Number of Intensities with I .LT. - 2*sig(I) ..           1      
PLAT791_ALERT_4_G The Model has Chirality at C9      (Verify) ....          R      
PLAT791_ALERT_4_G The Model has Chirality at C12     (Verify) ....          R      
PLAT791_ALERT_4_G The Model has Chirality at C13     (Verify) ....          R      
PLAT791_ALERT_4_G The Model has Chirality at C33     (Verify) ....          R      
PLAT791_ALERT_4_G The Model has Chirality at C36     (Verify) ....          R      
PLAT791_ALERT_4_G The Model has Chirality at C37     (Verify) ....          R      
PLAT808_ALERT_5_G No Parsable SHELXL style Weighting Scheme Found           !
PLAT929_ALERT_4_G No Interpretable (SHELX) Weight Parameters found          ?

   0 ALERT level A = In general: serious problem
   1 ALERT level B = Potentially serious problem
   5 ALERT level C = Check and explain
  10 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   6 ALERT type 3 Indicator that the structure quality may be low
   9 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check