3-Methoxalylchromone‒a novel versatile reagent for the regioselective purine isostere synthesis.
Mkrtchyan, Satenik; Iaroshenko, Viktor O.; Dudkin, Sergii; Gevorgyan, Ashot; Vilches-Herrera, Marcelo; Ghazaryan, Gagik; Volochnyuk, Dmitriy M.; Ostrovskyi, Dmytro; Ahmed, Zeeshan; Villinger, Alexander; Sosnovskikh, Vyacheslav Ya; Langer, Peter; Organic & biomolecular chemistry 8 (2010) 5280–5284; doi:10.1039/c0ob00379d

data_7153489
_publ_section_title
;
 3-Methoxalylchromone--a novel versatile reagent for the regioselective
 purine isostere synthesis.
;
_journal_issue                   23
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              5280
_journal_page_last               5284
_journal_paper_doi               10.1039/c0ob00379d
_journal_volume                  8
_journal_year                    2010
_chemical_formula_moiety         '2(C25 H19 N3 O5), C3 H7 N O'
_chemical_formula_sum            'C26.5 H22.5 N3.5 O5.5'
_chemical_formula_weight         477.98
_chemical_name_systematic
;
?
;
_space_group_IT_number           15
_symmetry_cell_setting           monoclinic
_symmetry_Int_Tables_number      15
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/c 1'
_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                 95.317(13)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   12.244(9)
_cell_length_b                   14.288(10)
_cell_length_c                   26.562(19)
_cell_measurement_reflns_used    2621
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      47.038
_cell_measurement_theta_min      4.763
_cell_volume                     4627(6)
_computing_cell_refinement       'Bruker Apex v2.0-2'
_computing_data_collection       'Bruker Apex v2.0-2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'ORTEP-3 (Farrugia, 1997)'
_computing_publication_material  SHELXL-97
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker Apex Kappa II-CCD-diffractometer'
_diffrn_measurement_method       'phi and psi scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0592
_diffrn_reflns_av_sigmaI/netI    0.0790
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       35
_diffrn_reflns_limit_l_min       -34
_diffrn_reflns_number            21990
_diffrn_reflns_theta_full        28.00
_diffrn_reflns_theta_max         28.00
_diffrn_reflns_theta_min         2.20
_exptl_absorpt_coefficient_mu    0.098
_exptl_absorpt_correction_T_max  0.9961
_exptl_absorpt_correction_T_min  0.9741
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 2004)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.372
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             2000
_exptl_crystal_size_max          0.27
_exptl_crystal_size_mid          0.26
_exptl_crystal_size_min          0.04
_refine_diff_density_max         0.200
_refine_diff_density_min         -0.220
_refine_diff_density_rms         0.048
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.954
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     351
_refine_ls_number_reflns         5597
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.954
_refine_ls_R_factor_all          0.1177
_refine_ls_R_factor_gt           0.0490
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0440P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0892
_refine_ls_wR_factor_ref         0.1039
_reflns_number_gt                3081
_reflns_number_total             5597
_reflns_threshold_expression     >2\s(I)
_cod_data_source_file            c0ob00379d.txt
_cod_data_source_block           is_sd047
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_original_formula_sum        'C26.50 H22.50 N3.50 O5.50'
_cod_database_code               7153489