Seven-Membered Ring Nucleoside Analogues: Stereoselective Synthesis and Studies on Their Conformational Properties.
Habibian, Maryam; Martínez-Montero, Saúl; Portella, Guillem; Chua, Zhijie; Bohle, D. Scott; Orozco, Modesto; Damha, Masad J.; Organic letters 17 (2015) 5416–5419; doi:10.1021/acs.orglett.5b02769

data_1555396
_publ_section_title
;
 Seven-Membered Ring Nucleoside Analogues: Stereoselective Synthesis and
 Studies on Their Conformational Properties.
;
_journal_issue                   21
_journal_name_full               'Organic letters'
_journal_page_first              5416
_journal_page_last               5419
_journal_paper_doi               10.1021/acs.orglett.5b02769
_journal_volume                  17
_journal_year                    2015
_chemical_absolute_configuration unk
_chemical_formula_moiety         'C12 H16 N2 O6, C H4 O'
_chemical_formula_sum            'C13 H20 N2 O7'
_chemical_formula_weight         316.31
_space_group_crystal_system      orthorhombic
_space_group_IT_number           19
_space_group_name_Hall           'P 2ac 2ab'
_space_group_name_H-M_alt        'P 21 21 21'
_atom_sites_solution_hydrogens   mixed
_audit_creation_method           SHELXL-2014/6
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   7.5247(4)
_cell_length_b                   13.1309(7)
_cell_length_c                   15.0660(8)
_cell_measurement_reflns_used    8986
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      27.94
_cell_measurement_theta_min      2.70
_cell_volume                     1488.61(14)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-2014/6 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.953
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0222
_diffrn_reflns_av_unetI/netI     0.0182
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 0.953
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            17089
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 0.930
_diffrn_reflns_theta_full        25.000
_diffrn_reflns_theta_max         28.421
_diffrn_reflns_theta_min         2.057
_diffrn_source                   'fine-focus sealed tube'
_exptl_absorpt_coefficient_mu    0.115
_exptl_absorpt_correction_T_max  0.7457
_exptl_absorpt_correction_T_min  0.7061
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS V2008/1 (Bruker AXS)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.411
_exptl_crystal_description       block
_exptl_crystal_F_000             672
_exptl_crystal_size_max          0.586
_exptl_crystal_size_mid          0.298
_exptl_crystal_size_min          0.239
_refine_diff_density_max         0.426
_refine_diff_density_min         -0.414
_refine_diff_density_rms         0.053
_refine_ls_abs_structure_details
;
 Flack x determined using 1347 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.2(3)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.076
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     215
_refine_ls_number_reflns         3489
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.076
_refine_ls_R_factor_all          0.0376
_refine_ls_R_factor_gt           0.0353
_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^)+(0.0594P)^2^+0.4838P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0976
_refine_ls_wR_factor_ref         0.0993
_reflns_Friedel_coverage         0.699
_reflns_Friedel_fraction_full    1.000
_reflns_Friedel_fraction_max     0.898
_reflns_number_gt                3306
_reflns_number_total             3489
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ol5b02769_si_003.cif
_cod_data_source_block           smhmabs
_cod_database_code               1555396
_shelx_estimated_absorpt_t_min   0.936
_shelx_estimated_absorpt_t_max   0.973
_shelxl_version_number           2014/6
_shelx_res_checksum              79321
_shelx_hkl_checksum              26654