Valdecoxib vs. borazavaldecoxib: isoxazole BN/CC isosterism as a case study in designing and stabilizing boron heterocycles.
Boghi, Michele; Hall, Dennis G.; Organic & biomolecular chemistry 16 (2018) 4849–4856; doi:10.1039/c8ob00998h

data_7156278
_publ_section_title
;
 Valdecoxib vs. borazavaldecoxib: isoxazole BN/CC isosterism as a case
 study in designing and stabilizing boron heterocycles.
;
_journal_issue                   26
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              4849
_journal_page_last               4856
_journal_paper_doi               10.1039/c8ob00998h
_journal_volume                  16
_journal_year                    2018
_chemical_formula_moiety         'C16 H14 N2 O2'
_chemical_formula_sum            'C16 H14 N2 O2'
_chemical_formula_weight         266.29
_chemical_name_common            'compound 7'
_chemical_name_systematic
3,7a-Diphenyl-5,6-dihydro[1,3]oxazolo[3,2-d][1,2,4]oxadiazole
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2ybc'
_space_group_name_H-M_alt        'P 1 21/c 1'
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2016/6
_audit_update_record
;
2018-04-17 deposited with the CCDC.
2018-06-08 downloaded from the CCDC.
;
_cell_angle_alpha                90
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_cell_formula_units_Z            4
_cell_length_a                   8.9000(2)
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_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      73.79
_cell_measurement_theta_min      5.41
_cell_volume                     1345.80(7)
_computing_cell_refinement       'Bruker SAINT'
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_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-2016/6 (Sheldrick, 2016)'
_computing_structure_solution    'SHELXD (Schneider & Sheldrick, 2002)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.972
_diffrn_measured_fraction_theta_max 0.966
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0354
_diffrn_reflns_av_unetI/netI     0.0262
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_diffrn_reflns_limit_h_max       11
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_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            9199
_diffrn_reflns_point_group_measured_fraction_full 0.972
_diffrn_reflns_point_group_measured_fraction_max 0.966
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_diffrn_reflns_theta_min         5.406
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_exptl_absorpt_correction_T_min  0.5852
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details   'SADABS 2016/2 (Krause et al., 2015)'
_exptl_crystal_colour            colourless
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_exptl_crystal_description       fragment
_exptl_crystal_F_000             560
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_refine_ls_extinction_method     none
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_refine_ls_matrix_type           full
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_refine_ls_number_reflns         2621
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.034
_refine_ls_R_factor_all          0.0409
_refine_ls_R_factor_gt           0.0403
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0597P)^2^+0.3398P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1058
_refine_ls_wR_factor_ref         0.1064
_reflns_Friedel_coverage         0.000
_reflns_number_gt                2545
_reflns_number_total             2621
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c8ob00998h2.cif
_cod_data_source_block           dgh1706
_cod_depositor_comments
'Adding full bibliography for 7156277--7156280.cif.'
_cod_database_code               7156278
_shelx_shelxl_version_number     2016/6
_shelx_estimated_absorpt_t_min   0.625
_shelx_estimated_absorpt_t_max   0.917
_shelx_res_checksum              175