Facile synthesis and conformation of 3′-O,4′-C-methyleneribonucleosides
Obika, Satoshi; Morio, Ken-ichiro; Hari, Yoshiyuki; Imanishi, Takeshi; Chemical Communications  (1999) 2423–; doi:10.1039/a907218g

data_7110707
_publ_contact_author             'Takeshi Imanishi'
_publ_section_title
;
 Facile synthesis and conformation of
 3&#x2032;-O,4&#x2032;-C-methyleneribonucleosides
;
_journal_issue                   23
_journal_name_full               'Chemical Communications'
_journal_page_first              2423
_journal_paper_doi               10.1039/a907218g
_journal_year                    1999
_chemical_formula_analytical     'C11 H16 N2 O7'
_chemical_formula_moiety         'C11 H14 N2 O6'
_chemical_formula_structural     'C11 H14 N2 O6'
_chemical_formula_sum            'C11 H16 N2 O7'
_chemical_formula_weight         288.26
_chemical_melting_point          119.5(5)
_chemical_name_common
;
3',O-4'-C-methylene-5-methyluridine
;
_chemical_name_systematic
;
3',O-4'-C-methylene-5-methyluridine
;
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_date             98-12-14
_audit_creation_method           SHELXL
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.6242(10)
_cell_length_b                   20.6008(8)
_cell_length_c                   7.2767(11)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    283(2)
_cell_measurement_theta_max      30.0
_cell_measurement_theta_min      25.0
_cell_volume                     1292.8(3)
_computing_cell_refinement       'MSC / AFC (MSC, 1991)'
_computing_data_collection       'MSC / AFC (MSC, 1991)'
_computing_data_reduction        'MSC / AFC (MSC, 1991)'
_computing_molecular_graphics    'ORTEP-II (Johnson, 1994)'
_computing_structure_refinement  'SHELXL-93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS-86 (Sheldrick, 1990)'
_diffrn_ambient_temperature      283(2)
_diffrn_measurement_device       'Rigaku AFC5'
_diffrn_measurement_method       '2theta-omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Rigaku RU-300 rotating Cu anode'
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.54051
_diffrn_reflns_av_R_equivalents  0.0059
_diffrn_reflns_av_sigmaI/netI    0.0213
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       24
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            1177
_diffrn_reflns_theta_max         61.98
_diffrn_reflns_theta_min         4.29
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 200
_diffrn_standards_interval_time  0.6
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    1.075
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.481
_exptl_crystal_density_meas      ?
_exptl_crystal_description       plate
_exptl_crystal_F_000             608
_exptl_crystal_size_max          0.30
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.127
_refine_diff_density_min         -0.166
_refine_diff_density_rms         0.044
_refine_ls_abs_structure_details
;
The absolute configration was assigned to agree with the known chirality
from its precursor D-glucose'
;
_refine_ls_abs_structure_Flack   -0.14(41)
_refine_ls_extinction_coef       0
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_all   1.080
_refine_ls_goodness_of_fit_obs   1.093
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     245
_refine_ls_number_reflns         1155
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.080
_refine_ls_restrained_S_obs      1.093
_refine_ls_R_factor_all          0.0379
_refine_ls_R_factor_obs          0.0321
_refine_ls_shift/esd_max         0.002
_refine_ls_shift/esd_mean        0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[s^2^(Fo^2^)+( 0.0548P)^2^+0.1329P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.0854
_refine_ls_wR_factor_obs         0.0806
_reflns_number_observed          1037
_reflns_number_total             1155
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            907218gsup1.cif
_cod_data_source_block           1
_cod_depositor_comments
;
The following automatic conversions were performed:

'_chemical_melting_point' value '119-120' was changed to '119.5(5)' -
the average value was taken and precision was estimated.

Automatic conversion script
Id: cif_fix_values 1891 2012-01-12 08:04:46Z andrius 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc w=1/[s^2^(Fo^2^)+(
0.0548P)^2^+0.1329P] where P=(Fo^2^+2Fc^2^)/3' was changed to 'calc'.
New tag '_refine_ls_weighting_details' was created. The value of the
new tag was set to 'w=1/[s^2^(Fo^2^)+( 0.0548P)^2^+0.1329P] where
P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_database_code               7110707