A practical, convergent route to the key precursor to the tetracycline antibiotics.
Kummer, David A.; Li, Derun; Dion, Amelie; Myers, Andrew G.; Chemical science (Royal Society of Chemistry : 2010) 2 (2011) 1710–1718; doi:10.1039/C1SC00303H

data_1515647
_publ_section_title
;
 A practical, convergent route to the key precursor to the tetracycline
 antibiotics.
;
_journal_issue                   9
_journal_name_full
'Chemical science (Royal Society of Chemistry : 2010)'
_journal_page_first              1710
_journal_page_last               1718
_journal_paper_doi               10.1039/C1SC00303H
_journal_volume                  2
_journal_year                    2011
_chemical_formula_sum            'C20 H18 N2 O4'
_chemical_formula_weight         350.36
_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                101.300(15)
_cell_angle_beta                 98.534(14)
_cell_angle_gamma                106.220(14)
_cell_formula_units_Z            2
_cell_length_a                   8.4645(18)
_cell_length_b                   9.265(2)
_cell_length_c                   13.880(3)
_cell_measurement_reflns_used    1308
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      20.26
_cell_measurement_theta_min      2.24
_cell_volume                     1000.8(4)
_computing_cell_refinement       'Bruker Saint v7.23A (Bruker, 2005)'
_computing_data_collection       'APEX II (Bruker, 2007)'
_computing_data_reduction        'Bruker Saint v7.23A (Bruker, 2005)'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.968
_diffrn_measured_fraction_theta_max 0.968
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
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_diffrn_reflns_limit_h_min       -10
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_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            11619
_diffrn_reflns_theta_full        26.06
_diffrn_reflns_theta_max         26.06
_diffrn_reflns_theta_min         2.36
_exptl_absorpt_coefficient_mu    0.082
_exptl_absorpt_correction_T_max  0.9975
_exptl_absorpt_correction_T_min  0.9870
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS (Bruker, 2005)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.163
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             368
_exptl_crystal_size_max          0.16
_exptl_crystal_size_mid          0.08
_exptl_crystal_size_min          0.03
_refine_diff_density_max         0.236
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_refine_ls_extinction_method     none
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_refine_ls_matrix_type           full
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_refine_ls_number_reflns         3833
_refine_ls_number_restraints     289
_refine_ls_restrained_S_all      0.967
_refine_ls_R_factor_all          0.1916
_refine_ls_R_factor_gt           0.0895
_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^)+(0.0136P)^2^+1.6470P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1646
_refine_ls_wR_factor_ref         0.1873
_reflns_number_gt                1391
_reflns_number_total             3833
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c1sc00303h.txt
_cod_data_source_block           AD-1-290-impunety
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
according to
/usr/data/users/saulius/automatic-downloads/retrospective/RSC/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from
2011-04-26.

'_exptl_absorpt_correction_type' value 'MULTI-SCAN'
changed to 'multi-scan' according to
/usr/data/users/saulius/automatic-downloads/retrospective/RSC/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 2281 2013-09-26 08:29:07Z andrius 
;
_cod_original_sg_symbol_H-M      P-1
_cod_database_code               1515647