Interpretation of substituent effects on (13)C and (15)N NMR chemical shifts in 6-substituted purines.
Standara, Stanislav; Bouzková, Kateřina; Straka, Michal; Zacharová, Zuzana; Hocek, Michal; Marek, Jaromír; Marek, Radek; Physical chemistry chemical physics : PCCP 13 (2011) 15854–15864; doi:10.1039/c1cp20680j

data_7206435
_publ_section_title
;
 Interpretation of substituent effects on (13)C and (15)N NMR chemical
 shifts in 6-substituted purines.
;
_journal_issue                   35
_journal_name_full               'Physical chemistry chemical physics : PCCP'
_journal_page_first              15854
_journal_page_last               15864
_journal_paper_doi               10.1039/c1cp20680j
_journal_volume                  13
_journal_year                    2011
_chemical_formula_sum            'C13 H9 N5'
_chemical_formula_weight         235.25
_chemical_name_common            7-benzyl-7H-purine-6-carbonitrile
_chemical_name_systematic
;
7-benzyl-7H-purine-6-carbonitrile
;
_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                   4.9475(7)
_cell_length_b                   10.0332(12)
_cell_length_c                   21.929(3)
_cell_measurement_reflns_used    3472
_cell_measurement_temperature    120(2)
_cell_measurement_theta_max      28.2085
_cell_measurement_theta_min      2.293
_cell_volume                     1088.5(3)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      120(2)
_diffrn_detector_area_resol_mean 8.3611
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'KUMA KM4 + CCD'
_diffrn_measurement_method       'rotation method, \w--scan'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Enhance (Mo) X-ray Source'
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0760
_diffrn_reflns_av_sigmaI/netI    0.0610
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       26
_diffrn_reflns_limit_l_min       -25
_diffrn_reflns_number            6624
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         3.45
_exptl_absorpt_coefficient_mu    0.093
_exptl_absorpt_correction_type   none
_exptl_crystal_density_diffrn    1.435
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             488
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.171
_refine_diff_density_min         -0.165
_refine_diff_density_rms         0.041
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.992
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     163
_refine_ls_number_reflns         1910
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.992
_refine_ls_R_factor_all          0.0531
_refine_ls_R_factor_gt           0.0450
_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^)+(0.0375P)^2^+0.2500P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0882
_refine_ls_wR_factor_ref         0.0924
_reflns_number_gt                1733
_reflns_number_total             1910
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c1cp20680j.txt
_cod_data_source_block           rm-1g
_cod_depositor_comments
;
The following automatic conversions were performed:
'_atom_site_symetry_multiplicity' tag replaced with
'_atom_site_symmetry_multiplicity'.

Automatic conversion script
Id: cif_correct_tags 1440 2010-10-19 06:21:57Z saulius 
;
_cod_original_formula_sum        'C13 H9 N5 '
_cod_database_code               7206435