A direct entry to polycyclic quinoxaline derivatives <i>via</i> I<sub>2</sub>-DMSO mediated oxidative decarboxylation of α-amino acids and the subsequent Pictet-Spengler cyclization reaction.
Samanta, Surya Kanta; Sarkar, Rumpa; Sengupta, Utsav; Das, Sayan; Ganguly, Debabani; Hasija, Avantika; Chopra, Deepak; Bera, Mrinal K.; Organic & biomolecular chemistry 20 (2022) 4650–4658; doi:10.1039/d2ob00503d

data_7158699
_publ_section_title
;
 A direct entry to polycyclic quinoxaline derivatives <i>via</i>
 I<sub>2</sub>-DMSO mediated oxidative decarboxylation of \a-amino acids
 and the subsequent Pictet-Spengler cyclization reaction.
;
_journal_issue                   22
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              4650
_journal_page_last               4658
_journal_paper_doi               10.1039/d2ob00503d
_journal_volume                  20
_journal_year                    2022
_chemical_formula_moiety         'C21 H14 N2'
_chemical_formula_sum            'C21 H14 N2'
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Olex2 1.3
(compiled 2020.11.12 svn.r5f609507 for OlexSys, GUI svn.r6408)
;
_audit_update_record
;
2022-03-06 deposited with the CCDC.	2022-05-16 downloaded from the CCDC.
;
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_computing_structure_solution    'SHELXS-97 (Sheldrick 2008)'
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_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
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_diffrn_reflns_limit_l_min       -23
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_refine_ls_R_factor_all          0.1222
_refine_ls_R_factor_gt           0.0981
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_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.1200P)^2^+2.4749P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2533
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_reflns_Friedel_fraction_full    1.000
_reflns_Friedel_fraction_max     1.000
_reflns_number_gt                2037
_reflns_number_total             2645
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d2ob00503d2.cif
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_cod_depositor_comments
'Adding full bibliography for 7158698--7158699.cif.'
_cod_database_code               7158699
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_max   0.980
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_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups
2.a Aromatic/amide H refined with riding coordinates:
 C3(H3), C11(H11), C12(H12), C13(H13), C14(H14), C15(H15), C16(H16), C17(H17),
 C18(H18), C19(H19), C20(H20), C21(H21), C22(H22), C23(H23)
;
_smtbx_masks_void_probe_radius   1.2
_smtbx_masks_void_truncation_radius 1.2
_shelx_res_checksum              65559
_olex2_submission_special_instructions 'No special instructions were received'