Novel formal synthesis of cephalotaxine via a facile Friedel-Crafts cyclization.
Li, Wei-Dong Z; Wang, Xin-Wei; Organic letters 9 (2007) 1211–1214; doi:10.1021/ol070024b

data_1505319
_publ_section_title
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 Novel formal synthesis of cephalotaxine via a facile Friedel-Crafts
 cyclization.
;
_journal_issue                   7
_journal_name_full               'Organic letters'
_journal_page_first              1211
_journal_page_last               1214
_journal_paper_doi               10.1021/ol070024b
_journal_volume                  9
_journal_year                    2007
_chemical_formula_sum            'C18 H21 N O4'
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_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 99.323(4)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.576(2)
_cell_length_b                   7.6040(18)
_cell_length_c                   24.573(6)
_cell_measurement_reflns_used    2190
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_cell_measurement_theta_max      23.84
_cell_measurement_theta_min      2.41
_cell_volume                     1581.3(7)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      294(2)
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
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_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       25
_diffrn_reflns_limit_l_min       -30
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_diffrn_reflns_theta_max         26.41
_diffrn_reflns_theta_min         1.68
_exptl_absorpt_coefficient_mu    0.094
_exptl_absorpt_correction_T_max  1.000000
_exptl_absorpt_correction_T_min  0.655777
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_exptl_absorpt_process_details   SADABS
_exptl_crystal_density_diffrn    1.325
_exptl_crystal_density_meas      ?
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_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0749P)^2^+0.1333P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
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_cod_data_source_file            ol070024bsi20070104_114125.cif
_cod_data_source_block           060404b
_cod_depositor_comments
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The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.1 from
2010-06-29.

'_exptl_absorpt_correction_type' value 'MULTI-SCAN'
changed to 'multi-scan' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.1 from
2010-06-29.

'_refine_ls_hydrogen_treatment' value 'CONSTR' changed
to 'constr' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'NONE' was changed to '?' - the
value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
;
_cod_original_cell_volume        1581.2(7)
_cod_original_sg_symbol_H-M      P2(1)/c
_cod_database_code               1505319