Synthesis and conformational analysis of new cyclobutane-fused nucleosides.
Alibés, Ramon; Alvárez-Larena, Angel; de March, Pedro; Figueredo, Marta; Font, Josep; Parella, Teodor; Rustullet, Albert; Organic letters 8 (2006) 491–494; doi:10.1021/ol052794y

data_1505841
_publ_section_title
;
 Synthesis and conformational analysis of new cyclobutane-fused
 nucleosides.
;
_journal_issue                   3
_journal_name_full               'Organic letters'
_journal_page_first              491
_journal_page_last               494
_journal_paper_doi               10.1021/ol052794y
_journal_volume                  8
_journal_year                    2006
_chemical_formula_sum            'C12 H15 N5 O2'
_chemical_formula_weight         261.29
_chemical_name_systematic
;
(1R,2R,4S,5S)-9-(4-hydroxymethyl-3-oxabicyclo[3.2.0]hept-2-yl)adenine
;
_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   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.873(2)
_cell_length_b                   8.231(2)
_cell_length_c                   18.935(5)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      14.01
_cell_measurement_theta_min      10.05
_cell_volume                     1227.0(5)
_computing_cell_refinement       'CAD4 (Enraf-Nonius)'
_computing_data_collection       'CAD4 (Enraf-Nonius)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-86 (Sheldrick, 1985)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.837
_diffrn_measured_fraction_theta_max 0.837
_diffrn_measurement_device_type  'Enraf-Nonius CAD4'
_diffrn_measurement_method       'omega/2theta scan'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  0.0000
_diffrn_reflns_av_sigmaI/netI    0.0178
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            1049
_diffrn_reflns_theta_full        24.80
_diffrn_reflns_theta_max         24.80
_diffrn_reflns_theta_min         2.15
_diffrn_standards_decay_%        0
_diffrn_standards_interval_time  60
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.101
_exptl_absorpt_correction_T_max  1.000
_exptl_absorpt_correction_T_min  1.000
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.414
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             552
_exptl_crystal_size_max          0.48
_exptl_crystal_size_mid          0.19
_exptl_crystal_size_min          0.12
_refine_diff_density_max         0.121
_refine_diff_density_min         -0.127
_refine_diff_density_rms         0.033
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   4.9(18)
_refine_ls_extinction_coef       0.009(2)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.026
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     182
_refine_ls_number_reflns         1049
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.025
_refine_ls_R_factor_all          0.0348
_refine_ls_R_factor_gt           0.0291
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0596P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0752
_refine_ls_wR_factor_ref         0.0762
_reflns_number_gt                927
_reflns_number_total             1049
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol052794ysi20051118_094225.cif
_cod_data_source_block           c315
_cod_depositor_comments
;
 Removing the "?" symbol from the _chemical_name_systematic data item value.

 Antanas Vaitkus,
 2017-03-30
;
_cod_database_code               1505841