The interplay between hydrogen bonding and π-π stacking interactions in the crystal packing of N1-thyminyl derivatives, and implications for the photo-chemical [2π + 2π]-cycloaddition of thyminyl compounds.
Johnston, Priscilla; Izgorodina, Ekaterina I.; Saito, Kei; Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology 11 (2012) 1938–1951; doi:10.1039/c2pp25228g

data_1515315
_publ_section_title
;
 The interplay between hydrogen bonding and \p-\p stacking interactions in
 the crystal packing of N1-thyminyl derivatives, and implications for the
 photo-chemical [2\p + 2\p]-cycloaddition of thyminyl compounds.
;
_journal_issue                   12
_journal_name_full
'Photochemical &amp; photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology'
_journal_page_first              1938
_journal_page_last               1951
_journal_paper_doi               10.1039/c2pp25228g
_journal_volume                  11
_journal_year                    2012
_chemical_formula_moiety         'C8 H10 N2 O4'
_chemical_formula_sum            'C8 H10 N2 O4'
_chemical_formula_weight         198.18
_chemical_name_common            'Thymine PropOic'
_chemical_name_systematic
;
Thymine propanoic acid
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 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                 101.90(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   4.9130(10)
_cell_length_b                   20.405(4)
_cell_length_c                   8.5920(17)
_cell_measurement_temperature    100(2)
_cell_volume                     842.8(3)
_computing_cell_refinement       XDS
_computing_data_collection       'Blu Ice'
_computing_data_reduction        XDS
_computing_molecular_graphics    X-Seed
_computing_publication_material  CIFTAB
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.903
_diffrn_measured_fraction_theta_max 0.903
_diffrn_measurement_device_type  '\f goniostat with quantum 210r detector'
_diffrn_measurement_method       'f scan'
_diffrn_radiation_monochromator  'silicone double crystal'
_diffrn_radiation_source         'MX1 Beamline, Australian Synchrotron'
_diffrn_radiation_type           synchrotron
_diffrn_radiation_wavelength     0.71072
_diffrn_reflns_av_R_equivalents  0.1273
_diffrn_reflns_av_sigmaI/netI    0.0840
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       24
_diffrn_reflns_limit_k_min       -24
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            8717
_diffrn_reflns_theta_full        24.99
_diffrn_reflns_theta_max         24.99
_diffrn_reflns_theta_min         2.00
_exptl_absorpt_coefficient_mu    0.127
_exptl_absorpt_correction_T_max  0.9975
_exptl_absorpt_correction_T_min  0.9949
_exptl_crystal_colour            Colourless
_exptl_crystal_density_diffrn    1.562
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Prism
_exptl_crystal_F_000             416
_exptl_crystal_size_max          0.12
_exptl_crystal_size_mid          0.07
_exptl_crystal_size_min          0.03
_refine_diff_density_max         0.308
_refine_diff_density_min         -0.336
_refine_diff_density_rms         0.073
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.075
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     136
_refine_ls_number_reflns         1336
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.075
_refine_ls_R_factor_all          0.0601
_refine_ls_R_factor_gt           0.0577
_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^)+(0.0885P)^2^+0.5739P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1552
_refine_ls_wR_factor_ref         0.1568
_reflns_number_gt                1245
_reflns_number_total             1336
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c2pp25228g.txt
_cod_data_source_block           ThyPropOic_Cmpd6
_cod_original_sg_symbol_H-M      P21/n
_cod_database_code               1515315