Synthesis of Proline-Based Diketopiperazine Scaffolds
N. Deppermann; A. H. G. P. Prenzel; A. Beitat; W. Maison; Journal of Organic Chemistry 74 (2009) 4267–4271; doi:10.1021/jo9004876

data_4024568
_publ_section_title
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Synthesis of Proline-Based Diketopiperazine Scaffolds
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              4267
_journal_page_last               4271
_journal_paper_doi               10.1021/jo9004876
_journal_volume                  74
_journal_year                    2009
_chemical_absolute_configuration syn
_chemical_formula_sum            'C17 H24 N2 O6'
_chemical_formula_weight         352.38
_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                   9.1263(7)
_cell_length_b                   11.5380(10)
_cell_length_c                   16.9865(12)
_cell_measurement_temperature    193(2)
_cell_volume                     1788.7(2)
_computing_cell_refinement       'STOE IPDS Software (1997)'
_computing_data_collection       'STOE IPDS Software (1997)'
_computing_data_reduction        'STOE IPDS Software (1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      193(2)
_diffrn_measured_fraction_theta_full 0.990
_diffrn_measured_fraction_theta_max 0.990
_diffrn_measurement_device_type  'STOE IPDS'
_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  0.0505
_diffrn_reflns_av_sigmaI/netI    0.0396
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            16049
_diffrn_reflns_theta_full        28.05
_diffrn_reflns_theta_max         28.05
_diffrn_reflns_theta_min         2.53
_exptl_absorpt_coefficient_mu    0.099
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.309
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             752
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.32
_exptl_crystal_size_min          0.32
_refine_diff_density_max         0.174
_refine_diff_density_min         -0.172
_refine_diff_density_rms         0.033
_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   0.987
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     299
_refine_ls_number_reflns         4295
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.987
_refine_ls_R_factor_all          0.0514
_refine_ls_R_factor_gt           0.0380
_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^)+(0.0570P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0864
_refine_ls_wR_factor_ref         0.0918
_reflns_number_gt                3462
_reflns_number_total             4295
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo9004876_si_002.cif
_cod_data_source_block           mais002w
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Orthorhombic' changed to 'orthorhombic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 
;
_cod_original_sg_symbol_H-M      P212121
_cod_database_code               4024568