Synthesis and stereochemical analysis of β-nitromethane substituted γ-amino acids and peptides.
Ganesh Kumar, Mothukuri; Mali, Sachitanand M.; Gopi, Hosahudya N.; Organic & biomolecular chemistry 11 (2013) 803–813; doi:10.1039/c2ob27070f

data_7152803
_publ_section_title
;
 Synthesis and stereochemical analysis of \b-nitromethane substituted
 \g-amino acids and peptides.
;
_journal_issue                   5
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              803
_journal_page_last               813
_journal_paper_doi               10.1039/c2ob27070f
_journal_volume                  11
_journal_year                    2013
_chemical_absolute_configuration syn
_chemical_compound_source        Synthesis
_chemical_formula_sum            'C15 H27 N O4'
_chemical_formula_weight         285.37
_chemical_name_common
'(S,E)-ethyl 4-(tert-butoxycarbonylamino)-6-methylhept-2-enoate'
_chemical_name_systematic
'(S,E)-ethyl 4-(tert-butoxycarbonylamino)-6-methylhept-2-enoate'
_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           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 106.331(5)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   10.340(3)
_cell_length_b                   9.733(3)
_cell_length_c                   18.073(5)
_cell_measurement_temperature    296(2)
_cell_volume                     1745.5(9)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_pressure         101.325
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.960
_diffrn_measured_fraction_theta_max 0.960
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0277
_diffrn_reflns_av_sigmaI/netI    0.0372
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            6755
_diffrn_reflns_theta_full        24.28
_diffrn_reflns_theta_max         24.28
_diffrn_reflns_theta_min         1.17
_diffrn_source                   'fine-focus sealed tube'
_diffrn_source_type              'Graphite Monochromator'
_exptl_absorpt_coefficient_mu    0.078
_exptl_absorpt_correction_T_max  0.982
_exptl_absorpt_correction_T_min  0.969
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            Colorless
_exptl_crystal_density_diffrn    1.086
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'Retangular block'
_exptl_crystal_F_000             624
_exptl_crystal_recrystallization_method Methanol
_exptl_crystal_size_max          0.45
_exptl_crystal_size_mid          0.34
_exptl_crystal_size_min          0.24
_refine_diff_density_max         0.110
_refine_diff_density_min         -0.130
_refine_diff_density_rms         0.027
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.7(13)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.985
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     373
_refine_ls_number_reflns         2788
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.985
_refine_ls_R_factor_all          0.0431
_refine_ls_R_factor_gt           0.0341
_refine_ls_shift/su_max          0.004
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0504P)^2^+0.1961P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0804
_refine_ls_wR_factor_ref         0.0896
_reflns_number_gt                2413
_reflns_number_total             2788
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c2ob27070f.txt
_cod_data_source_block           anudgleu
_cod_original_cell_volume        1745.5(8)
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               7152803