Research Article
MedChemComm
4.1.3. General procedure for the synthesis of
triphenylphosphonium salts 5, 7, 8, 9, 13 and 15. A mixture
of triterpenoids 1–4, 11 or 12 (0.40 mmol), acetonitrile (13
mL) and Ph3P (2 mmol) was refluxed for 20–35 h to prepare
the triphenylphosphonium salts [TLC monitoring hexane/
EtOAc 10 : 1]. The solution was cooled and the solvent was
evaporated under vacuum. The solid product obtained was
washed with hot hexane (2 × 10 mL), dissolved in EtOAc (2–4
mL), and diluted with hexane (12 ml). The precipitate was fil-
tered to obtain the title product.
4-(Triphenylphosphonio)butyl-3β-hydroxylup-20IJ29)-en-28-
oate bromide (5). White crystals; 79% yield; mp 150–152 °C
(EtOH); [α]2D1 −0.38° (c 1.85, CHCl3); IR (CHCl3) νmax: 3446
(–OH), 1718 (C=O); 31P NMR (161 MHz, CDCl3) δ 24.49; 1H
NMR (400 MHz, CDCl3) δ 0.73, 0.77, 0.79, 0.90, 0.94 (3H
each, all s, H-23–H-27), 0.63–2.12 (m, 24H, CH, CH2 in
pentacyclic skeleton, 4H, H-2′, H-3′), 1.63 (s, 3H, H-30),
2.87–2.89 (m, 1H, H-19), 3.15–3.18 (m, 1H, H-3), 3.96–4.13
(m, 4H, H-4′, H-1′), 4.56 (s, 1H, H-29), 4.66 (s, 1H, H-29),
7.69–7.86 (m, 15H, Ph); 13C NMR (100 MHz, CDCl3) δ 14.65
(C-27), 15.41 (C-26), 15.96 (C-25), 16.13 (C-24), 18.27 (C-6),
19.27 (C-30), 19.42 (d, J = 3 Hz, C-3′), 20.81 (C-11), 22.30 (d,
J = 50 Hz, 4′), 25.41 (C-12), 27.37 (C-2), 27.99 (C-23), 29.28
(d, J = 17 Hz, 2′), 29.57 (C-21), 30.52 (C-15), 32.00 (C-16),
34.29 (C-7), 36.91 (C-22), 37.14 (C-1), 38.13 (C-4), 38.68 (C-
13), 38.83 (C-10), 40.61 (C-8), 42.31 (C-14), 46.91 (C-18),
49.30 (C-19), 50.46 (C-9), 55.28 (C-5), 56.42 (C-17), 62.75 (C-
1′), 78.81 (C-3), 109.70 (C-29), 117.85 (d, J = 85 Hz, Ph),
130.50 (d, J = 13 Hz, Ph), 133.70 (d, J = 10 Hz, Ph), 135.03
(br s, Ph), 150.37 (C-20), 175.91 (C-28); MS: m/z [M−Br]−,
found 773.49. [C52H70BrO3P]+ requires 852.42.
8′-(Triphenylphosphonio-3′,6′-dioxaoctan-1′-yl)-3β-acetoxylup-
20IJ29)-en-28-oate bromide (7). White crystals; 70% yield; mp
108–110 °C (EtOH); [α]D18 +9.6° (c 0.50, CHCl3); IR (CHCl3)
νmax: 1727 (CO) cm−1; 31P NMR (161 MHz, CDCl3) δ 25.50;
1H NMR (500 MHz, CDCl3) δ 0.81, 0.82, 0.83, 0.88, 0.94 (3H
each, all s, H-23–H-27), 0.76–2.25 (m, 24H, CH, CH2 in
pentacyclic skeleton), 1.67 (s, 3H, H-30), 2.02 (s, 3H,
CH3CO–), 3.28–3.29 (m, 1H, H-19), 3.33–3.40 (m, 6H, H-4′, H-
5′, H-7′), 3.89–3.96 (m, 2H, H-8′), 4.07–4.19 (m, 4H, H-1′, H-
2′), 4.43–4.47 (m, 1H, H-3), 4.59 (s, 1H, H-29), 4.70 (s, 1H, H-
29), 7.64–7.83 (m, 15H, Ph); 13C NMR (126 MHz, CDCl3) δ
14.64 (C-27), 16.02 (C-26), 16.20 (C-25), 16.48 (C-24), 18.16 (C-
6), 19.26 (C-30), 20.89 (C-11), 21.31 (CH3CO–), 23.66 (C-12),
25.42 (C-8′, J = 52 Hz), 25.43 (C-2), 27.92 (C-23), 29.59 (C-15),
30.51 (C-16), 32.03 (C-21), 34.26 (C-7), 36.98 (C-22), 37.08 (C-
1), 37.77 (C-4), 38.19 (C-13), 38.36 (C-10), 40.70 (C-8), 42.38
(C-14), 46.98 (C-18), 49.33 (C-19), 50.41 (C-9), 55.39 (C-5),
56.51 (C-17), 62.50 (C-1′), 64.06 (C-7′, J = 7 Hz), 69.01, 69.85,
70.24 (C-2′, C-4′, C-5′), 80.88 (C-3), 109.75 (C-29), 118.91 (Ph, J
= 86 Hz), 130.07 (Ph, J = 12.7 Hz), 134.04 (Ph, J = 10.2 Hz),
61 °C (EtOH); [α]D17.5 +7.5° (c 0.39, CHCl3); IR (CHCl3) νmax
:
1727 (CO) cm−1; 31P NMR (161 MHz, CDCl3) δ 25.57; 1H
NMR (500 MHz, CDCl3) δ 0.80, 0.82, 0.83, 0.89, 0.95 (3H
each, all s, H-23–H-27), 0.77–2.25 (m, 24H, CH, CH2 in
pentacyclic skeleton), 1.68 (s, 3H, H-30), 2.03 (s, 3H,
CH3CO–), 2.30 (s, 3H, OTs-CH3), 2.96–2.99 (m, 1H, H-19),
3.26–3.38 (m, 6H, H-4′, H-5′, H-7′), 3.84–4.07 (m, 6H, H-1′, H-
2′, H-8′), 4.44–4.48 (m, 1H, H-3), 4.60 (s, 1H, H-29), 4.71 (s,
1H, H-29), 7.05 (d, 2H, J = 2 Hz, Ph), 7.62–7.80 (m, 15H, Ph
and 2H, OTs-Ph); 13C NMR (126 MHz, CDCl3) δ 14.65 (C-27),
16.02 (C-26), 16.21 (C-25), 16.49 (C-24), 18.17 (C-6), 19.28 (C-
30), 20.90 (C-11), 21.29 (CH3CO–), 21.32 (OTs-CH3), 23.67 (C-
12), 24.43 (C-8′, J = 54 Hz), 25.45 (C-2), 27.93 (C-23), 29.60 (C-
15), 30.53 (C-16), 32.04 (C-21), 34.27 (C-7), 36.99 (C-22), 37.09
(C-1), 37.78 (C-4), 38.20 (C-13), 38.38 (C-10), 40.70 (C-8), 42.39
(C-14), 46.99 (C-18), 49.34 (C-19), 50.42 (C-9), 55.40 (C-5),
56.51 (C-17), 62.53 (C-1′), 63.06 (C-7′, J = 7.4 Hz), 68.97, 69.84,
70.08 (C-2′, C-4′, C-5′), 80.88 (C-3), 109.75 (C-29), 119.11 (Ph, J
= 86 Hz), 130.00 (Ph, J = 12.7 Hz), 134.00 (Ph, J = 10.2 Hz),
134.53 (Ph, J = 2.6 Hz), 126.11, 128.32, 138.54, 144.31, (OTs-
Ph), 150.41 (C-20), 171.01 (CH3CO–), 175.89 (C-28); MS: m/z
[M − TsO]−, found 875.32. [C63H83O8PS]+ requires 1030.55.
9′-(Triphenylphosphonio-3′,6′-dioxaoctan-1′-yl)-3β-
hydroxylup-20IJ29)-en-28-oate bromide (9). White crystals; 69%
yield; mp 95–97 °C (EtOH); [α]1D8 +3.32° (c 0.62, CHCl3); IR
(CHCl3) νmax: 3370 (−OH), 1722 (CO) cm−1; 31P NMR (161
1
MHz, CDCl3) δ 25.45; H NMR (500 MHz, CDCl3) δ 0.72, 0.77,
0.86, 0.93, 0.94 (3H each, all s, H-23–H-27), 0.64–2.19 (m,
24H, CH, CH2 in pentacyclic skeleton), 1.65 (s, 3H, H-30),
2.93–2.95 (m, 1H, H-19), 3.15–3.17 (m, 1H, H-3), 3.15–3.39
(m, 6H, H-4′, H-5′, H-7′), 3.88–3.93 (m, 2H, H-8′), 4.06–4.14
(m, 4H, H-1′, H-2′), 4.57 (s, 1H, H-29), 4.69 (s, 1H, H-29),
7.64–7.83 (m, 15H, Ph); 13C NMR (125 MHz, CDCl3) δ 14.68
(C-27), 15.42 (C-26), 16.01 (C-25), 16.14 (C-24), 18.27 (C-6),
19.28 (C-30), 20.87 (C-11), 25.41 (C-8′, J = 52 Hz), 25.46 (C-12),
27.34 (C-2), 27.99 (C-23), 29.59 (C-21), 30.52 (C-15), 32.04 (C-
16), 34.32 (C-7), 36.97 (C-22), 37.15 (C-1), 38.21 (C-4), 38.68
(C-13), 38.82 (C-10), 40.67 (C-8), 42.38 (C-14), 46.96 (C-18),
49.33 (C-19), 50.47 (C-9), 55.29 (C-5), 56.51 (C-17), 62.51 (C-
1′), 64.06 (C-7′, J = 7 Hz), 69.01, 69.84, 70.24 (C-2′, C-4′, C-5′),
78.80 (C-3), 109.70 (C-29), 118.82 (Ph, J = 87 Hz), 130.07 (Ph, J
= 12.7 Hz), 134.03 (Ph, J = 10.2 Hz), 134.69 (Ph, J = 2.6 Hz),
150.42 (C-20), 175.88 (C-28); MS: m/z [M−Br]−, found 833.32.
[C54H74BrO5P]+ requires 912.45.
4-(Triphenylphosphonio)butyl-3β-hydroxyurs-12-en-28-oate
bromide (13). White crystals; 85% yield; mp 166–168 °C (EtOH);
[α]2D0 +3.02° (c 0.50, CHCl3); IR (CHCl3) νmax: 3367 (–OH), 1716
(CO); 31P NMR (161 MHz, CDCl3) δ 24.48; 1H NMR (400 MHz,
CDCl3) δ 0.64, 0.77, 0.87, 0.98, 1.03 (3H each, all s, H-23–H-27),
0.82, 0.93 (3H each, both d, J = 6 Hz, H-29, H-30), 0.67–2.10 (m,
22H, CH, CH2 in pentacyclic skeleton, 4H, H-2′, H-3′), 2.08 (d,
1H, J = 10.4 Hz, H-18), 3.20 (dd, 1H, J = 10.4, 4.4 Hz, H-3), 3.94–
4.08 (m, 4H, H-4′, H-1′), 5.07 (br s, 1H, H-12), 7.68–7.80 (m, 15H,
Ph); 13C NMR (100 MHz, CDCl3) δ 15.47 (C-25), 15.67 (C-24),
17.01 (C-26), 17.02 (C-29), 18.29 (C-6), 19.43 (d, J = 3 Hz, C-3′),
21.16 (C-30), 22.30 (d, J = 50 Hz, 4′), 23.27 (C-11), 23.52 (C-27),
134.65 (Ph, J = 2.6 Hz), 150.40 (C-20), 171.01 (CH CO–),
_
3
175.88 (C-28); MS: m/z [M−Br]−, found 875.33. [C56H76BrO6P]+
requires 954.46.
8′-(Triphenylphosphonio-3′,6′-dioxaoctan-1′-yl)-3β-acetoxylup-
20IJ29)-en-28-oate tosyl (8). White crystals; 91% yield; mp 59–
Med. Chem. Commun.
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