Cyclo(<small>L</small>-leucyl-α,β-dehydrophenylalanine): the first diketopiperazine containing an α,β-dehydrophenylalanine residue
Bagaria, A.; Ramakumar, S.; Gupta, M.; Chauhan, V. S.; Acta Crystallographica Section C 61 (2005) o174–o176; doi:10.1107/S0108270105001629

data_2014633
_publ_section_title
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 Cyclo(<small>L</small>-leucyl-\a,\b-dehydrophenylalanine): the first
 diketopiperazine containing an \a,\b-dehydrophenylalanine residue
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_journal_issue                   3
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              o174
_journal_page_last               o176
_journal_paper_doi               10.1107/S0108270105001629
_journal_volume                  61
_journal_year                    2005
_chemical_formula_iupac          'C15 H18 N2 O2'
_chemical_formula_moiety         'C15 H18 N2 O2'
_chemical_formula_sum            'C15 H18 N2 O2'
_chemical_formula_weight         258.31
_chemical_name_common            Leu-Phe*
_chemical_name_systematic        3-benzylidene-6-isobutylpiperazine-2,5-dione
_space_group_IT_number           1
_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
_cell_angle_alpha                69.3440(10)
_cell_angle_beta                 78.0540(10)
_cell_angle_gamma                79.3960(10)
_cell_formula_units_Z            2
_cell_length_a                   6.2384(5)
_cell_length_b                   9.8255(7)
_cell_length_c                   12.5432(9)
_cell_measurement_reflns_used    5071
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      54
_cell_measurement_theta_min      4
_cell_volume                     698.64(9)
_computing_cell_refinement       'SAINT-Plus (Bruker, 2001)'
_computing_data_collection       'SMART (Bruker, 1998)'
_computing_data_reduction        SAINT-Plus
_computing_molecular_graphics
'ORTEPIII (Farrugia, 1997) and PLATON (Spek, 2003)'
_computing_publication_material
'WinGx (Farrugia, 1999) and PARST (Nardelli, 1995)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.909
_diffrn_measurement_device_type  'Bruker SMART CCD area-detector'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0165
_diffrn_reflns_av_sigmaI/netI    0.0187
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            7333
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         27.34
_diffrn_reflns_theta_min         1.76
_exptl_absorpt_coefficient_mu    0.082
_exptl_absorpt_correction_T_max  0.988
_exptl_absorpt_correction_T_min  0.865
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 1996)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.228
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       rod
_exptl_crystal_F_000             276
_exptl_crystal_size_max          0.46
_exptl_crystal_size_mid          0.26
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.25
_refine_diff_density_min         -0.17
_refine_ls_extinction_coef       0.018(5)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL97 (Sheldrick, 1997)'
_refine_ls_goodness_of_fit_ref   1.11
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     348
_refine_ls_number_reflns         2872
_refine_ls_number_restraints     3
_refine_ls_restrained_S_all      1.11
_refine_ls_R_factor_all          0.0490
_refine_ls_R_factor_gt           0.0450
_refine_ls_shift/su_max          0.013
_refine_ls_shift/su_mean         0.003
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[\s^2^(Fo^2^)+(0.058P)^2^+0.0935] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1100
_refine_ls_wR_factor_ref         0.1127
_reflns_number_gt                2649
_reflns_number_total             2872
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            bm1602.cif
_cod_data_source_block           I
_cod_depositor_comments
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The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
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_cod_database_code               2014633
_cod_database_fobs_code          2014633