Asymmetric Syntheses of APTO and AETD: the β-Amino Acid Fragments within Microsclerodermins C, D, and E
Stephen G. Davies; Ai M. Fletcher; Emma M. Foster; James A. Lee; Paul M. Roberts; James E. Thomson; Journal of Organic Chemistry 78 (2013) 2500–2510; doi:10.1021/jo302731m

data_4028053
_publ_contact_author             'Stephen G. Davies'
_publ_contact_author_email       steve.davies@chem.ox.ac.uk
_publ_contact_author_fax         '+44 1865 275633'
_publ_contact_author_phone       '+44 1865 275695'
_publ_section_title
;
 Asymmetric Syntheses of APTO and AETD: the \b-Amino Acid Fragments within
 Microsclerodermins C, D, and E
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              2500
_journal_page_last               2510
_journal_paper_doi               10.1021/jo302731m
_journal_volume                  78
_journal_year                    2013
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C23 H33 N1 O7'
_chemical_formula_sum            'C23 H33 N O7'
_chemical_formula_weight         435.52
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   5.49231(8)
_cell_length_b                   16.4313(3)
_cell_length_c                   25.7470(4)
_cell_measurement_reflns_used    0
_cell_measurement_temperature    150
_cell_measurement_theta_max      0
_cell_measurement_theta_min      0
_cell_volume                     2323.56(7)
_computing_cell_refinement       'CrysAlis, (Oxford Diffraction, 2002)'
_computing_data_collection       'SuperNova, (Oxford Diffraction, 2010)'
_computing_data_reduction        'CrysAlis, (Oxford Diffraction, 2002)'
_computing_molecular_graphics    'CAMERON (Watkin et al., 1996)'
_computing_publication_material  'CRYSTALS (Betteridge et al., 2003)'
_computing_structure_refinement  'CRYSTALS (Betteridge et al., 2003)'
_computing_structure_solution    'SIR92 (Altomare et al., 1994)'
_diffrn_ambient_temperature      150
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device       Area
_diffrn_measurement_device_type  'Oxford Diffraction SuperNova'
_diffrn_measurement_method       \w/2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.023
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -3
_diffrn_reflns_limit_k_max       20
_diffrn_reflns_limit_k_min       -20
_diffrn_reflns_limit_l_max       32
_diffrn_reflns_limit_l_min       -30
_diffrn_reflns_number            11091
_diffrn_reflns_theta_full        75.230
_diffrn_reflns_theta_max         76.765
_diffrn_reflns_theta_min         3.191
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.756
_exptl_absorpt_correction_T_max  0.9629
_exptl_absorpt_correction_T_min  0.9272
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.245
_exptl_crystal_description       block
_exptl_crystal_F_000             936
_exptl_crystal_size_max          0.270
_exptl_crystal_size_mid          0.100
_exptl_crystal_size_min          0.050
_refine_diff_density_max         0.18
_refine_diff_density_min         -0.17
_refine_ls_abs_structure_details 'Flack (1983), 0 Friedel-pairs'
_refine_ls_abs_structure_Flack   -0.08(9)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.0000
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     281
_refine_ls_number_reflns         10112
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0333
_refine_ls_R_factor_gt           0.0306
_refine_ls_shift/su_max          0.0009890
_refine_ls_shift/su_mean         0.0000931
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
;
 Method, part 1, Chebychev polynomial, (Watkin, 1994, Prince, 1982) 
 [weight] = 1.0/[A~0~*T~0~(x)+A~1~*T~1~(x) ... +A~n-1~]*T~n-1~(x)] 
 where A~i~ are the Chebychev coefficients listed below and x= Fcalc/Fmax 
 Method = Robust Weighting (Prince, 1982) 
 W = [weight] * [1-(deltaF/6*sigmaF)^2^]^2^ 
 A~i~ are: 
 972. 0.161E+04 0.101E+04 457. 126. 
;
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.0779
_refine_ls_wR_factor_gt          0.0748
_refine_ls_wR_factor_ref         0.0779
_reflns_limit_h_max              6
_reflns_limit_h_min              -6
_reflns_limit_k_max              20
_reflns_limit_k_min              0
_reflns_limit_l_max              32
_reflns_limit_l_min              0
_reflns_number_gt                9486
_reflns_number_total             2815
_reflns_threshold_expression     I>2.0\s(I)
_oxford_diffrn_Wilson_B_factor   2.47
_oxford_diffrn_Wilson_scale      0.03
_oxford_refine_ls_r_factor_ref   0.0333
_oxford_refine_ls_scale          5.15(4)
_oxford_reflns_number_all        10112
_oxford_reflns_threshold_expression_ref I>-3.0\s(I)
_cod_data_source_file            jo302731m_si_001_4.cif
_cod_data_source_block           42
_cod_original_cell_volume        2323.57(6)
_cod_original_formula_sum        'C23 H33 N1 O7'
_cod_database_code               4028053