US 10,007,180 B2  132  131  Thereafter, 100 g of chloroform was added to the mixture,  and the resultant organic phase was sequentially washed  with water, a saturated aqueous sodium bicarbonate solution  and water. The solvent was removed, thereby obtaining  brown liquid compound (A-1-3).  (Compound (A-1-3) was dissolved in 50 g of water, and  3.6 g of compound (A-1-4) was added to the aqueous  solution and agitated for 30 minutes. Thereafter, 100 g of  chloroform was added to the mixture, and the resultant  organic phase was washed with water, thereby obtaining 3.3  g of brown liquid compound (A-1 ).  The $^{1}$H-NMR analytical result of compound (A-1) is as  follows.  $^{1}$H-NMR (300 MHz, CDC1$_{3}$ ); 7.78-7.62 (m, 12H), 7.55  (d, 2H), 4.22 (m, 2H), 3.95 (d, lH), 3.76 (d, lH), 3.23 (m,  lH), 3.13 (s, 2H), 3.04 (t, lH), 2.65 (t, lH), 2.40 (m, 4H),  1.82-1.55 (m, SH), 1.48-1.20 (m, 6H), 1.14-0.84 (m, 3H).  Compounds (A-2) to (A-14) listed in Table 1 were syn› thesized through salt exchanges between sulfonium bromide  and sodium sulfonate in the same manner as in the synthesis  of compound (A-1). Table 1 also shows the structures of  comparative compounds (Rl) to (R4) employed as com› parative examples.  TABLE 1  A-1  Compd.(A)  Compd.  (A-1)  Compd.  (A-2)  Compd.  (A-3)  Structural formula  F  F  0  TifilIT Cb  0-S  S-N  II  F  F  II  0  F  0  F*F  F  a  I  0  II  ~  0-S  F  II  0  F  I  L_J=\_-0  /N~  r+  \  ;f  oJ l  ,ij  rrl  tt’Y~  0  0  Vol.(A 3 )  of  generated  acid  311  127  277 