2',3'-Dideoxy-3'-<i>C</i>,2'-<i>N</i>-[(3<i>R</i>,5<i>R</i>)-5-ethoxycarbonyl-2-methyl-1,2-isoxazolidine]ribothymidine
Burkhart, B. M.; Papchikhin, A.; Chattopadhyaya, J.; Sundaralingam, M.; Acta Crystallographica Section C 51 (1995) 1462–1464; doi:10.1107/S0108270194014332

data_2003648
_publ_section_title
2',3'-Dideoxy-3'-<i>C</i>,2'-<i>N</i>-[(3<i>R</i>,5<i>R</i>)-5-ethoxycarbonyl-2-methyl-1,2-isoxazolidine]ribothymidine
_journal_issue                   7
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              1462
_journal_page_last               1464
_journal_paper_doi               10.1107/S0108270194014332
_journal_volume                  51
_journal_year                    1995
_chemical_formula_moiety         'C15 H21 N3 O7'
_chemical_formula_sum            'C15 H21 N3 O7'
_chemical_formula_weight         355.35
_chemical_name_systematic
;
2',3'-dideoxy-3'-C-2'-N-[N(R)-methyl-5-(R)-ethoxycarbonyl-1,2-isoxazolidine]
ribothymidine
;
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_audit_creation_method           SHELXL93
_cell_angle_alpha                90.00
_cell_angle_beta                 93.43(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   5.5020(10)
_cell_length_b                   15.3840(10)
_cell_length_c                   9.918(2)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    295(2)
_cell_measurement_theta_max      30
_cell_measurement_theta_min      22
_cell_volume                     838.0(2)
_computing_cell_refinement       'MSC/AFC Diffractometer Control Software'
_computing_data_collection
;
MSC/AFC Diffractometer Control Software
(Molecular Structure Corporation, 1988)
;
_computing_data_reduction        'MSC/AFC Diffractometer Control Software'
_computing_structure_refinement  'SHELXL93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS86 (Sheldrick, 1990)'
_diffrn_ambient_temperature      295(2)
_diffrn_measurement_device       'Rigaku AFC5S four-circle'
_diffrn_measurement_method       \w/2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71070
_diffrn_reflns_av_R_equivalents  0.0000
_diffrn_reflns_av_sigmaI/netI    0.0589
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       20
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            2010
_diffrn_reflns_theta_max         27.56
_diffrn_reflns_theta_min         2.06
_diffrn_standards_decay_%        4.5
_diffrn_standards_interval_count 50
_diffrn_standards_number         6
_exptl_absorpt_coefficient_mu    0.113
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.408
_exptl_crystal_description       trapezoid
_exptl_crystal_F_000             376
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.38
_exptl_crystal_size_min          0.27
_refine_diff_density_max         0.165
_refine_diff_density_min         -0.144
_refine_ls_abs_structure_details 'Flack  (1983)'
_refine_ls_abs_structure_Flack   -0.74(161)
_refine_ls_extinction_coef       0.0037(25)
_refine_ls_extinction_method     'SHELXL93 (Sheldrick, 1993)'
_refine_ls_goodness_of_fit_all   1.050
_refine_ls_goodness_of_fit_obs   1.091
_refine_ls_matrix_type           full
_refine_ls_number_parameters     291
_refine_ls_number_reflns         2003
_refine_ls_number_restraints     8
_refine_ls_restrained_S_all      1.408
_refine_ls_restrained_S_obs      1.089
_refine_ls_R_factor_all          0.0762
_refine_ls_R_factor_obs          0.0369
_refine_ls_shift/esd_max         0.000
_refine_ls_shift/esd_mean        0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_scheme
; calc w = 1/[\s^2^(F~o~^2^) + (0.0279P)^2^ + 0.1537P]
where P = (F~o~^2^ + 2F~c~^2^)/3
;
_refine_ls_wR_factor_all         0.1311
_refine_ls_wR_factor_obs         0.0834
_reflns_number_observed          1447
_reflns_number_total             2010
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            cr1159.cif
_cod_data_source_block           nt
_cod_original_sg_symbol_H-M      P21
_cod_database_code               2003648