Stereospecific Synthesis of Conformationally Constrained γ-Amino Acids: New Foldamer Building Blocks That Support Helical Secondary Structure
Li Guo; Yonggui Chi; Aaron M. Almeida; Ilia A. Guzei; Brian K. Parker; Samuel H. Gellman; Journal of the American Chemical Society 131 (2009) 16018–16020; doi:10.1021/ja907233q

data_4105328
_publ_contact_author_address
;
Department of Chemistry
University of Wisconsin-Madison
1101 University Ave
Madison, WI  53706
USA
;
_publ_contact_author_email       iguzei@chem.wisc.edu
_publ_contact_author_fax         608-262-0381
_publ_contact_author_name
;
Guzei, Ilia A. 
;
_publ_contact_author_phone       608-263-4694
_publ_section_title
;
 Stereospecific Synthesis of Conformationally Constrained \g-Amino Acids:
 New Foldamer Building Blocks That Support Helical Secondary Structure
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              16018
_journal_page_last               16020
_journal_paper_doi               10.1021/ja907233q
_journal_volume                  131
_journal_year                    2009
_chemical_absolute_configuration syn
_chemical_formula_moiety         'C44 H64 N4 O7'
_chemical_formula_sum            'C44 H64 N4 O7'
_chemical_formula_weight         760.99
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_Int_Tables_number      4
_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
;
manual editing of the CIF file 
created by SHELXTL Ver. 6.10
and processed with modiCIfer-03272007. 
;
_cell_angle_alpha                90.00
_cell_angle_beta                 99.878(19)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   10.770(3)
_cell_length_b                   17.053(5)
_cell_length_c                   11.738(4)
_cell_measurement_reflns_used    9995
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      71.7051
_cell_measurement_theta_min      2.5905
_cell_volume                     2123.9(11)
_computing_cell_refinement       'SAINT Ver. 7.24A (Bruker-AXS, 2007)'
_computing_data_collection       'APEX2 Ver. 2.1-4 (Bruker-AXS, 2007)'
_computing_data_reduction        'SAINT Ver. 7.24A'
_computing_molecular_graphics    SHELXTL
_computing_publication_material  SHELXTL
_computing_structure_refinement  SHELXTL
_computing_structure_solution    'SHELXTL (Sheldrick, 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.984
_diffrn_measurement_device_type  'Bruker SMART APEX2 area detector'
_diffrn_measurement_method       '0.50\% \w and 0.5 \% \f scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           Cu-K\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0201
_diffrn_reflns_av_sigmaI/netI    0.0142
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -21
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            35684
_diffrn_reflns_theta_full        67.00
_diffrn_reflns_theta_max         72.20
_diffrn_reflns_theta_min         3.82
_exptl_absorpt_coefficient_mu    0.642
_exptl_absorpt_correction_T_max  0.8382
_exptl_absorpt_correction_T_min  0.7139
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS  (Bruker-AXS, 2007)
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.190
_exptl_crystal_description       block
_exptl_crystal_F_000             824
_exptl_crystal_size_max          0.56
_exptl_crystal_size_mid          0.31
_exptl_crystal_size_min          0.28
_refine_diff_density_max         0.190
_refine_diff_density_min         -0.152
_refine_diff_density_rms         0.031
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.00(8)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.038
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     519
_refine_ls_number_reflns         7776
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.038
_refine_ls_R_factor_all          0.0272
_refine_ls_R_factor_gt           0.0270
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0444P)^2^+0.3328P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0706
_refine_ls_wR_factor_ref         0.0708
_reflns_number_gt                7723
_reflns_number_total             7776
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            ja907233q_si_002.cif
_cod_data_source_block           gellman118
_cod_original_cell_volume        2123.8(11)
_cod_original_sg_symbol_Hall     'P 2yb       '
_cod_original_sg_symbol_H-M      'P 1 21 1 '
_cod_database_code               4105328