A synthesis of carbasugar-sugar pseudodisaccharides via a cycloaddition-cycloreversion reaction of 2H-pyran-2-ones.
Afarinkia, Kamyar; Haji Abdullahi, Mohamed; Scowen, Ian J.; Organic letters 12 (2010) 5564–5566; doi:10.1021/ol102358s

data_1503314
_publ_section_title
;
 A synthesis of carbasugar-sugar pseudodisaccharides via a
 cycloaddition-cycloreversion reaction of 2H-pyran-2-ones.
;
_journal_issue                   23
_journal_name_full               'Organic letters'
_journal_page_first              5564
_journal_page_last               5566
_journal_paper_doi               10.1021/ol102358s
_journal_volume                  12
_journal_year                    2010
_chemical_absolute_configuration syn
_chemical_formula_sum            'C20 H28 O8'
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_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           19
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_symmetry_space_group_name_Hall  'P 2ac 2ab'
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_cell_length_b                   10.1453(8)
_cell_length_c                   38.011(3)
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_computing_publication_material  'Bruker SHELXTL'
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_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.997
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_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
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_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.095
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_exptl_absorpt_correction_T_min  0.9607
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_exptl_crystal_colour            colourless
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_exptl_crystal_density_meas      ?
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_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0736P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1109
_refine_ls_wR_factor_ref         0.1324
_reflns_number_gt                1214
_reflns_number_total             2287
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol102358s_si_002.cif
_cod_data_source_block           mha215ab_imerge
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 

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 
;
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               1503314