A new short synthesis route for favipiravir and its analogue: Their tautomerization behaviour
Ghosh, Priyanka; Panda, Subhra Jyoti; Purohit, Chandra Shekhar; New Journal of Chemistry 46 (2022) 18824–18831; doi:10.1039/D2NJ02996K

data_7061912
_publ_section_title
;
 A new short synthesis route for favipiravir and its analogue: Their
 tautomerization behaviour
;
_journal_issue                   39
_journal_name_full               'New Journal of Chemistry'
_journal_page_first              18824
_journal_page_last               18831
_journal_paper_doi               10.1039/D2NJ02996K
_journal_volume                  46
_journal_year                    2022
_chemical_formula_moiety         '2(C7 H8 N2 O3), 2(H O0.5)'
_chemical_formula_sum            'C14 H18 N4 O7'
_chemical_formula_weight         354.32
_chemical_name_systematic        Ethyl_3-oxo-4-hydropyrazine-2-carboxylate
_space_group_crystal_system      monoclinic
_space_group_IT_number           13
_space_group_name_Hall           '-P 2yc'
_space_group_name_H-M_alt        'P 1 2/c 1'
_atom_sites_solution_hydrogens   mixed
_atom_sites_solution_primary     dual
_audit_creation_date             2020-12-07
_audit_creation_method
;
Olex2 1.3
(compiled Sep 10 2019 10:52:38 for OlexSys, GUI svn.r5938)
;
_audit_update_record
;
2020-12-07 deposited with the CCDC.	2022-09-21 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 111.662(3)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   20.5834(5)
_cell_length_b                   5.22440(10)
_cell_length_c                   15.7133(4)
_cell_measurement_reflns_used    8546
_cell_measurement_temperature    100.01(10)
_cell_measurement_theta_max      74.6190
_cell_measurement_theta_min      4.6540
_cell_volume                     1570.41(7)
_computing_cell_refinement       'CrysAlisPro 1.171.40.63a (Rigaku OD, 2019)'
_computing_data_collection       'CrysAlisPro 1.171.40.63a (Rigaku OD, 2019)'
_computing_data_reduction        'CrysAlisPro 1.171.40.63a (Rigaku OD, 2019)'
_computing_molecular_graphics    'Olex2 1.3 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.3 (Dolomanov et al., 2009)'
_computing_structure_refinement  'ShelXL 2018/3 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT 2014/5 (Sheldrick, 2014)'
_diffrn_ambient_environment      N~2~
_diffrn_ambient_temperature      100.01(10)
_diffrn_detector                 'Hybrid Pixel Array Detector'
_diffrn_detector_area_resol_mean 5.8140
_diffrn_detector_type            'Pilatus 200K'
_diffrn_measured_fraction_theta_full 0.986
_diffrn_measured_fraction_theta_max 0.961
_diffrn_measurement_details
;
List of Runs (angles in degrees, time in seconds):

  # Type    Start    End  Width  t~exp~   \w     \q     \k     \f   Frames
  1  \w    -70.00  24.00   0.50    2.20    --  -38.50  91.00  97.00  188
  2  \w     -3.00  80.00   0.50    2.20    --   48.56 -91.00 -16.00  166
  3  \w     32.00 106.00   0.50    8.79    --  101.38 -91.00 -16.00  148
  4  \w    104.00 171.00   0.50    8.79    --  101.38  91.00  97.00  134
  5  \w    -14.00  60.00   0.50    2.20    --   48.56 -57.00-180.00  148
  6  \w    -14.00  60.00   0.50    2.20    --   48.56 -57.00  30.00  148
  7  \w    103.00 166.00   0.50    8.79    --  101.38  77.00-180.00  126
  8  \w     32.00 109.00   0.50    8.79    --  101.38-111.00 -30.00  154
  9  \w     37.00 106.00   0.50    8.79    --  101.38 -45.00  60.00  138
 10  \w     33.00 105.00   0.50    8.79    --  101.38 -30.00 -90.00  144
 11  \w    103.00 166.00   0.50    8.79    --  101.38  77.00-120.00  126
 12  \w     39.00 115.00   0.50    8.79    --  101.38 -61.00-180.00  152
 13  \w     37.00 106.00   0.50    8.79    --  101.38 -45.00-180.00  138
 14  \w    103.00 166.00   0.50    8.79    --  101.38  77.00 -30.00  126
 15  \w     37.00 112.00   0.50    2.20    --   48.56  57.00 120.00  150
 16  \w     37.00 112.00   0.50    2.20    --   48.56  57.00-150.00  150
 17  \w     37.00 112.00   0.50    2.20    --   48.56  57.00  60.00  150
 18  \w     37.00 112.00   0.50    2.20    --   48.56  57.00 -30.00  150
 19  \w     98.00 129.00   0.50    8.79    --  101.38  30.00  60.00   62
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type
'SuperNova, Dual, Cu at home/near, Pilatus 200K'
_diffrn_measurement_method       '\w scans'
_diffrn_orient_matrix_type
'CrysAlisPro convention (1999,Acta A55,543-557)'
_diffrn_orient_matrix_UB_11      0.0562744000
_diffrn_orient_matrix_UB_12      0.1408674000
_diffrn_orient_matrix_UB_13      -0.0251176000
_diffrn_orient_matrix_UB_21      0.0476181000
_diffrn_orient_matrix_UB_22      -0.2372019000
_diffrn_orient_matrix_UB_23      0.0282674000
_diffrn_orient_matrix_UB_31      -0.0324155000
_diffrn_orient_matrix_UB_32      -0.1039194000
_diffrn_orient_matrix_UB_33      -0.0984523000
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0414
_diffrn_reflns_av_unetI/netI     0.0275
_diffrn_reflns_Laue_measured_fraction_full 0.986
_diffrn_reflns_Laue_measured_fraction_max 0.961
_diffrn_reflns_limit_h_max       25
_diffrn_reflns_limit_h_min       -25
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            12472
_diffrn_reflns_point_group_measured_fraction_full 0.986
_diffrn_reflns_point_group_measured_fraction_max 0.961
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         75.177
_diffrn_reflns_theta_min         4.623
_diffrn_source                   'micro-focus sealed X-ray tube'
_diffrn_source_type              'SuperNova (Cu) X-ray Source'
_exptl_absorpt_coefficient_mu    1.042
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.69610
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.40.63a (Rigaku Oxford Diffraction, 2019)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            'clear light colourless'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   light
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.499
_exptl_crystal_description       block
_exptl_crystal_F_000             744
_exptl_crystal_preparation       'AS PER MENTIONED IN PAPER'
_exptl_crystal_recrystallization_method 'SLOW EVAPORATION'
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.27
_exptl_crystal_size_min          0.2
_refine_diff_density_max         0.367
_refine_diff_density_min         -0.288
_refine_diff_density_rms         0.066
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.031
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     237
_refine_ls_number_reflns         3121
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.031
_refine_ls_R_factor_all          0.0519
_refine_ls_R_factor_gt           0.0491
_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^)+(0.0900P)^2^+0.7766P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1356
_refine_ls_wR_factor_ref         0.1385
_reflns_Friedel_coverage         0.000
_reflns_number_gt                2876
_reflns_number_total             3121
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d2nj02996k2.cif
_cod_data_source_block           1
_cod_depositor_comments
'Adding full bibliography for 7061906--7061913.cif.'
_cod_database_code               7061912
_shelx_shelxl_version_number     2018/3
_chemical_oxdiff_formula         'C4 H4 N4 O4 '
_shelx_estimated_absorpt_t_max   0.819
_shelx_estimated_absorpt_t_min   0.745
_reflns_odcompleteness_completeness 99.24
_reflns_odcompleteness_iscentric 1
_reflns_odcompleteness_theta     66.97
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups, All N(H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2.a Secondary CH2 refined with riding coordinates:
 C6(H6A,H6B), C13(H13A,H13B)
2.b Aromatic/amide H refined with riding coordinates:
 N2(H2), C3(H3), C4(H4), N4(H4A), C10(H10), C11(H11)
2.c Idealised Me refined as rotating group:
 C7(H7A,H7B,H7C), C14(H14A,H14B,H14C)
;
_shelx_res_checksum              73847
_olex2_exptl_crystal_mounting_method 'MOUNTED ON LOOP'
_olex2_submission_special_instructions 'No special instructions were received'
_oxdiff_exptl_absorpt_empirical_details
;
Empirical correction (ABSPACK) includes:
- Absorption correction using spherical harmonics
- Frame scaling
;
_oxdiff_exptl_absorpt_empirical_full_max 1.697
_oxdiff_exptl_absorpt_empirical_full_min 0.502