Efficient Macrocyclization of U-Turn Preorganized Peptidomimetics: The Role of Intramolecular H-Bond and Solvophobic Effects
Jorge Becerril; Michael Bolte; M. Isabel Burguete; Francisco Galindo; Enrique García-España; Santiago V. Luis; Juan F. Miravet; Journal of the American Chemical Society 125 (2003) 6677–6686; doi:10.1021/ja0284759

data_4113774
_publ_section_title
;
 Efficient Macrocyclization of U-Turn Preorganized Peptidomimetics: The
 Role of Intramolecular H-Bond and Solvophobic Effects
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              6677
_journal_page_last               6686
_journal_paper_doi               10.1021/ja0284759
_journal_volume                  125
_journal_year                    2003
_chemical_formula_sum            'C20 H32 N4 O2'
_chemical_formula_weight         360.50
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 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                 92.105(5)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   10.1580(6)
_cell_length_b                   18.8852(15)
_cell_length_c                   10.8306(6)
_cell_measurement_temperature    100(2)
_cell_volume                     2076.3(2)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.988
_diffrn_measured_fraction_theta_max 0.988
_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  0.0471
_diffrn_reflns_av_sigmaI/netI    0.0683
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       23
_diffrn_reflns_limit_k_min       -24
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            20452
_diffrn_reflns_theta_full        26.93
_diffrn_reflns_theta_max         26.93
_diffrn_reflns_theta_min         1.88
_exptl_absorpt_coefficient_mu    0.076
_exptl_absorpt_correction_T_max  0.9925
_exptl_absorpt_correction_T_min  0.9631
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.153
_exptl_crystal_description       needle
_exptl_crystal_F_000             784
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.162
_refine_diff_density_min         -0.140
_refine_diff_density_rms         0.037
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.9(7)
_refine_ls_extinction_coef       0.0069(4)
_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   0.913
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     502
_refine_ls_number_reflns         8830
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.913
_refine_ls_R_factor_all          0.0530
_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^)+(0.0247P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0659
_refine_ls_wR_factor_ref         0.0690
_reflns_number_gt                7027
_reflns_number_total             8830
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja0284759si20021216_125949.cif
_cod_data_source_block           jb12
_cod_database_code               4113774