US 9,703,193 B2  177  178  40 g of MIBK. The solid precipitate was removed by  filtration, whereupon the filtrate was washed 4 times with 30  g of water, combined with 2.23 g ofbenzyltrimethylammo› nium chloride and 40 g of water, and stirred for 30 minutes.  The organic layer was taken out and washed with 40 g water,  followed by vacuum concentration to remove the solvent.  Steps of diluting the concentrate with dichloroethane, add› ing 50 g of diisopropyl ether thereto, stirring, and removing  a supernatant were repeated 5 times, followed by vacuum  concentration. After the solvent removal, a powdery solid  was recovered and was dried in vacuum, obtaining 4.30 g of  the desired Intermediate 7 (yield 57%). Analytic results by  IR, $^{1}$H-NMR, $^{19}$F-NMR, and MALDI-TOF-MS are shown  below.  PAG-7 was synthesized according to the following  scheme.  $^{1}$H-NMR (500 MHz, DMSO-d$_{6}$ ):  o=4.37 (2H, m), 4.44 (2H, m), 6.97 (lH, d), 7.40 (lH, t),  7.46-7.53 (3H, m), 7.75-7.87 (16H, m), 8.21 (lH, m) ppm  $^{19}$F-NMR (500 MHz, DMSO-d$_{6}$ ): o=-78.8 (3F, s) ppm  MALDI-TOF-MS:  Positive M+ 263 (corresponding to C$_{18}$H$_{15}$S+)  Negative M- 398 (corresponding to C$_{10}$H$_{7}$O-(CH 2 ) 2 - OSO2N-sO2CF  3 )  0  0  II  II  F3C-s-N--S-O  II  II  ii:  °’  0  0  -W- Intermediate 7  0  0  II  II  F3C-s-N--S-O  II  II  0  0  I  PAG-7  Synthesis Example 7-1  Synthesis of Intermediate 7  Synthesis Example 7  Synthesis of PAG-7  Under ice cooling, a solution of 1.64 g of trifluorometh› anesulfonamide and 2.85 g of pyridine in 5 g of acetonitrile  was added dropwise to a solution of 1 .48 g of sulfuryl  chloride in 5 g of acetonitrile. The solution was stirred at  room temperature for 2.5 hours. A solution of 3.89 g of  ~-cholestanol and 0.12 g ofN,N-dimethylaminopyridine in  15 g of toluene was added dropwise to the solution at 50°  C.  The solution was stirred at 80°  C. for 21 hours for aging. The  reaction solution was quenched with 5 g of methanol. The  reaction solution was concentrated in vacuum and added to  IR (D-ATR):  v=3040,2930,2866,2849, 1490, 1475, 1458, 1418, 1376,  1310, 1221, 1188, 1136, 1066,949,937,904,891,866,848,  778, 727, 703, 662, 609, 596, 565 cm- 1  $^{1}$H-NMR (500 MHz, DMSO-d$_{5}$ ,  for only main isomer):  o=0.69 (4H, m), 0.75 (3H, s), 0.82-1.76 (37H, m), 1.90  (2H, m), 3.01 (9H, s), 4.27 (lH, m), 4.50 (2H, s), 7.53 (5H,  m) ppm  $^{19}$F-NMR (500 MHz, DMSO-d$_{6}$ ,  for only main isomer):  o=-78.8 (3F, s) ppm  MALDI-TOF-MS:  Positive M+ 150 (corresponding to C$_{10}$H$_{11}$N+)  Negative M- 598 (corresponding to C$_{27}$H$_{47}$OSO 2 N› SO2CF3) 