Aza-β^3^-cyclotetrapeptides
Arnaud Salaün; Clémence Mocquet; Romain Perochon; Aurélien Lecorgne; Barbara Le Grel; Michel Potel; Philippe Le Grel; Journal of Organic Chemistry 73 (2008) 8579–8582; doi:10.1021/jo8013963

data_4023795
_publ_section_title
;
 Aza-\b^3^-cyclotetrapeptides
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              8579
_journal_page_last               8582
_journal_paper_doi               10.1021/jo8013963
_journal_volume                  73
_journal_year                    2008
_chemical_formula_sum            'C27 H38 N8 O5'
_chemical_formula_weight         554.65
_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                93.015(2)
_cell_angle_beta                 105.207(2)
_cell_angle_gamma                109.4140(10)
_cell_formula_units_Z            2
_cell_length_a                   8.7804(2)
_cell_length_b                   11.7723(3)
_cell_length_c                   15.3624(4)
_cell_measurement_temperature    566(2)
_cell_volume                     1428.06(6)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      566(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_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  0.0366
_diffrn_reflns_av_sigmaI/netI    0.0392
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            25505
_diffrn_reflns_theta_full        27.51
_diffrn_reflns_theta_max         27.51
_diffrn_reflns_theta_min         2.48
_exptl_absorpt_coefficient_mu    0.092
_exptl_crystal_density_diffrn    1.290
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             592
_refine_diff_density_max         0.220
_refine_diff_density_min         -0.181
_refine_diff_density_rms         0.047
_refine_ls_extinction_coef       0.0085(18)
_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   1.046
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     382
_refine_ls_number_reflns         6536
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.046
_refine_ls_R_factor_all          0.0754
_refine_ls_R_factor_gt           0.0439
_refine_ls_shift/su_max          0.042
_refine_ls_shift/su_mean         0.002
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0666P)^2^+0.0897P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1124
_refine_ls_wR_factor_ref         0.1266
_reflns_number_gt                4360
_reflns_number_total             6536
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo8013963_si_001.cif
_cod_data_source_block           cyclo_3enk
_cod_database_code               4023795