(A) Synthesis and structure of CBRH16-Br (derivative of compound of Example 16 of Li et al. 2001a having bromine at position 3 of ring A). (i), (CH3CH2)3N/CH2Cl2; 0°C; 1 h. (ii), PCl5/C2H4Cl2; 70°C; 5 h. (iii), (CH3CH2)3N/NH2OH-HCl/CH3CN; 0-24°C.
(B) RNAP-inhibitory activities of CBRH16-Br.
(C) Growth-inhibitory activities of CBRH16-Br.
(D) Electron density, bromine anomalous difference density, and atomic model for CBRH16-Br. Green mesh: NCS-averaged mFo-DFc omit map for CBRH16-Br (contoured at 2.5σ). Pink mesh: bromine anomalous difference density for CBRH16-Br (contoured at 4.5σ). Other colors and labels as in Figure 2B,E.