Quassidines A-D, bis-beta-carboline alkaloids from the stems of Picrasma quassioides.
Jiao, Wei-Hua; Gao, Hao; Li, Chen-Yang; Zhao, Feng; Jiang, Ren-Wang; Wang, Ying; Zhou, Guang-Xiong; Yao, Xin-Sheng; Journal of natural products 73 (2010) 167–171; doi:10.1021/np900538r

data_1502823
_publ_section_title
;
 Quassidines A-D, bis-beta-carboline alkaloids from the stems of Picrasma
 quassioides.
;
_journal_issue                   2
_journal_name_full               'Journal of natural products'
_journal_page_first              167
_journal_page_last               171
_journal_paper_doi               10.1021/np900538r
_journal_volume                  73
_journal_year                    2010
_chemical_formula_sum            'C28 H28 N4 O5'
_chemical_formula_weight         500.55
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.472(8)
_cell_angle_beta                 90.815(8)
_cell_angle_gamma                91.818(10)
_cell_formula_units_Z            2
_cell_length_a                   6.3318(8)
_cell_length_b                   13.7667(18)
_cell_length_c                   13.9124(10)
_cell_measurement_temperature    293(2)
_cell_volume                     1211.9(2)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.769
_diffrn_measured_fraction_theta_max 0.769
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0164
_diffrn_reflns_av_sigmaI/netI    0.0234
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            5000
_diffrn_reflns_theta_full        23.87
_diffrn_reflns_theta_max         23.87
_diffrn_reflns_theta_min         1.46
_exptl_absorpt_coefficient_mu    0.090
_exptl_crystal_density_diffrn    1.328
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             512
_exptl_crystal_size_max          0.44
_exptl_crystal_size_mid          0.32
_exptl_crystal_size_min          0.23
_refine_diff_density_max         0.828
_refine_diff_density_min         -0.278
_refine_diff_density_rms         0.045
_refine_ls_extinction_coef       0.010(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.059
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     327
_refine_ls_number_reflns         2881
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.059
_refine_ls_R_factor_all          0.0527
_refine_ls_R_factor_gt           0.0463
_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^)+(0.0783P)^2^+0.5808P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1259
_refine_ls_wR_factor_ref         0.1306
_reflns_number_gt                2498
_reflns_number_total             2881
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            np900538r_si_003.cif
_cod_data_source_block           pqc7cu
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_sg_symbol_H-M      P-1
_cod_database_code               1502823