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PCB-183 Toda, M.; Matsumura, C.; Tsurukawa, M.; Okuno, T.; Nakano, T.; Inoue, Y.; Mori, T. J. Phys. Chem. A 2012, 116, 9340. (–)-o,p’-DDT is more cytotoxic than (+)-o,p’-DDT. (+)-o,p’-DDD is more cytotoxic than (–)-o,p’-DDD. 44% 3% 8% The absolute configurations of o,p'-DDT and o,p'-DDD studied by experimental and theoretical circular dichroisms Hiroki Tanaka, Takeshi Nakano, Mitsunobu Toda, Yuki Haga, Masahiro Tsurukawa, Chisato Matsumura, Tadashi Mori and Yoshihisa Inoue Osaka University and Hyogo prefectural Institute of Environmental Sciences Chiral insecticides Experimental and theoretical CD spectra of o,p’-DDT and o,p’-DDD Summary Theoretical CD spectra calculated at the SAC- CI/D95(d)//DFT-D3-TPSS/def2-TZVP reproduced the experimental ones. (+)-o,p’-DDT and (–)-o,p’-DDD have S-configurations. Theoretical and experimental CD spectra Enantiomer separation: preparative chiral HPLC on a Daicel Chiralcel OJ-H column eluted with n-hexane/isopropanol (9:1). Spectral measurement: in hexane at 25 °C. Conformers of o,p’-DDD Geometry optimization: Energy calculation: Spectral simulation: o,p’-DDT o,p’-Dichlorodiphenyl- trichloromethane (o,p’-DDT) o,p’-Dichlorodiphenyl- dichloromethane (o,p’-DDD) insecticide to control malaria and typhus Wang, C.; Li, Z.; Zhang, Q.; Zhao, M.; Liu, W. Environ. Sci. Technol. 2013, 47, 3909. Acetofenate For mosquitoes and flies. S-configuration is more toxic. Fipronil For cockroaches and ants. S-configuration is more toxic. DDT Zhao, M.; Liu, W. Environ. Toxicol. Chem. 2009, 28, 578. The absolute configuration controls pesticidal activities and toxicities. This work Determination of the absolute configurations of o,p’-DDT and o,p’-DDD We investigated experimentally and theoretically the CD spectra of o,p’-DDT and o,p’-DDD to unambiguously assign their absolute configurations. The absolute configuration can be determined by the theoretical calculation. SAC-CI (Symmetry adapted cluster/configuration interaction) o,p’-DDD The bands of thoretical spectra at longest wavelength: red-shifted because inverse hyperconjugation may be overestimated. at shortest wavelength: stronger than experimental ones because the diffuse function may not be enough. at 210-250 nm: reproduced the experimental ones satisfactorily. metabolite of DDT Evaluated by X-ray crystallography with better refinement parameters (the anomalous dispersion was not taken into account). Determined by chemical transformation to o,p’-DDT (see above). (–)-o,p’-DDT has R-configuration: (+)-o,p’-DDD has R-configuration: Smith, R. A.; Bennett, M. J. Acta Cryst. 1977, B33, 1126. Buser, H-R.; Muller, M.D. Anal. Chem. 1995, 67, 2691. DFT-D3-TPSS/def2-TZVP SCS-MP2/def2-TZVPP SAC-CI/D95(d) B-DNA (tetra model) RI-CC2 (resolution-of-identity, linear response, approximate coupled cluster) Ye, J.; Zhao, M.; Liu, J.; Liu, W. Environmental Pollution 2010, 158, 2371. Miyahara, T.; Nakatsuji, H.; Sugiyama, H. J. Phys. Chem. A 2013, 117, 42. Theoretical CD spectrum of o,p’-DDD was obtained by Boltzmann distribution assumed by the energy gap between various conformers (bg + and bg – : 0.0%). Theoretical CD spectrum of o,p’-DDT is a-form (population of a-form is >99.8%). o,p’-DDT 1st HPLC fraction: positive ([ ] D = +23) 2nd HPLC fraction: negative ([ ] D = –21) o,p’-DDD 1st HPLC fraction: negative ([ ] D = –57) 2nd HPLC fraction: positive ([ ] D = +61) Specific rotation (+)-o,p’-DDT and (–)-o,p’-DDD have S-configuration. (Match the past report) Cohn, B. A.; Wolff, M. S.; Cirillo, P. M.; Sholtz, R. I. Environ. Health Perspect. 2007, 115, 1406. DDT and DDD are POPs. DDT exposure may cause cancer. 2,6- Anthracenedicarboxylic acid dimer Wakai, A.; Fukasawa, H.; Cheng, Y.; Mori, T.; Inoue, Y. J. Am. Chem. Soc. 2012, 134, 4990. Application to persistent organic pollutants (POPs)
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