Oppolzer Sultam Directed Aldol as a Key Step for the Stereoselective Syntheses of Antitumor Antibiotic Belactosin C and Its Synthetic Congeners
Gullapalli Kumaraswamy; Mogilisetti Padmaja; Bekkam Markondaiah; Nivedita Jena; Balasubramanian Sridhar; Marelli Udaya Kiran; Journal of Organic Chemistry 71 (2006) 337–340; doi:10.1021/jo0516887

data_4021351
_publ_section_title
;
 Oppolzer Sultam Directed Aldol as a Key Step for the
 Stereoselective Syntheses of Antitumor Antibiotic Belactosin C
 and Its Synthetic Congeners
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              337
_journal_page_last               340
_journal_paper_doi               10.1021/jo0516887
_journal_volume                  71
_journal_year                    2006
_chemical_absolute_configuration unk
_chemical_formula_moiety         'C25 H37 N O5 S'
_chemical_formula_sum            'C25 H37 N O5 S'
_chemical_formula_weight         463.62
_chemical_name_systematic
; 
N-[(2R,3S methyl),2-[(2'-benzyloxyl-1'S-hydroxyl)
ethyl]pentanoyl] borane-10,2-sultam
;
_space_group_IT_number           18
_space_group_name_Hall           'P 2 2ab'
_space_group_name_H-M_alt        'P 21 21 2'
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2 2ab'
_symmetry_space_group_name_H-M   'P 21 21 2'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   18.3556(13)
_cell_length_b                   11.4102(8)
_cell_length_c                   11.9476(9)
_cell_measurement_reflns_used    4122
_cell_measurement_temperature    273(2)
_cell_measurement_theta_max      22.86
_cell_measurement_theta_min      2.21
_cell_volume                     2502.3(3)
_computing_cell_refinement       'SAINT (Bruker, 2001)'
_computing_data_collection       'SMART (Bruker, 2001)'
_computing_data_reduction        SAINT
_computing_molecular_graphics    'SHELXTL/PC (Sheldrick, 1990)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      273(2)
_diffrn_measured_fraction_theta_full 0.967
_diffrn_measured_fraction_theta_max 0.967
_diffrn_measurement_device       'Bruker SMART APEX CCD area-detector'
_diffrn_measurement_device_type  'CCD Area Detector'
_diffrn_measurement_method       '\w scan'
_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  0.0433
_diffrn_reflns_av_sigmaI/netI    0.0386
_diffrn_reflns_limit_h_max       22
_diffrn_reflns_limit_h_min       -23
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            15323
_diffrn_reflns_theta_full        28.04
_diffrn_reflns_theta_max         28.04
_diffrn_reflns_theta_min         1.70
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.164
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.231
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1000
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.15
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.360
_refine_diff_density_min         -0.170
_refine_diff_density_rms         0.050
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.049
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     293
_refine_ls_number_reflns         3294
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.049
_refine_ls_R_factor_all          0.0758
_refine_ls_R_factor_gt           0.0584
_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^)+(0.0869P)^2^+0.1750P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1399
_refine_ls_wR_factor_ref         0.1514
_reflns_number_gt                2540
_reflns_number_total             3294
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            jo0516887si20050810_073404_2.cif
_cod_database_code               4021351