A. E. M. Wammes et al. / Bioorg. Med. Chem. 22 (2014) 5593–5603
5601
2860, 2097, 1749, 1749, 1626, 1530, 1220, 672 cmꢁ1. HRMS (ESI)
calcd for C16H20N6NaO2 (M+Na)+ 351.1545, found 351.1563.
yield. 1H NMR (300 MHz, CDCl3) d 7.87 (d, J = 8.6 Hz, 2H), 7.76–
7.52 (m, 4H), 7.41 (d, J = 8.4 Hz, 2H), 4.78 (m, 1H), 4.40 (s, 2H),
1.75 (m, 1H), 1.61 (s, 2H), 0.99 (d, J = 4.5 Hz, 6H). 13C NMR
(75 MHz, CDCl3) d 184.93, 182.96, 174.04, 172.38, 167.26, 158.77,
146.60, 145.29, 144.03, 140.09, 135.44, 129.39, 128.94, 127.82,
127.43, 81.19, 74.03, 68.83, 46.70, 27.82. FTIR = 3292, 2957, 2098,
4.1.7. 4-(Azidomethyl)benzoyl-Phe-NHCH2CN (3c)
General procedure 3, using H-Phe-NHCH2CN (295 mg,
980 lmol) and EtOAc (10 mL). Column chromatography (MeOH/
CH2Cl2 1:19) afforded the expected product (230 mg; 95%) as white
crystals. Mp = 90–93 °C. RF = 0.39 (MeOH/CH2Cl2 1:19). 1H NMR
(CD3CN, 400 MHz) d = 7.81–7.76 (m, 1H), 7.49–7.43 (m, 2H), 7.33
(m, 5H), 7.26 (m, 1H), 4.82 (m, 1H), 4.49 (s, 2H), 4.10 (dd, J = 5.9,
4.0 Hz, 2H), 3.35 (dd, J = 14.0, 5.2 Hz, 1H), 3.09 (dd, J = 13.9,
9.4 Hz, 1H) ppm. 13C NMR (CD3CN, 75 MHz) d = 172.65, 167.54,
140.69, 138.51, 134.55, 131.01, 130.25, 129.41, 129.25, 128.67,
127.66, 118.31, 55.83, 54.62, 37.88, 28.22 ppm. FTIR = 3273,
3057, 2932, 2552, 2223, 2105, 1683, 1634, 1533, 1294,
1756, 1631, 1533, 1495, 1212, 668 cmꢁ1
.
4.1.12. 4-(Azidomethyl)biphenyl-Phe-NHCH2CN (4b)
General procedure 3, using H-Phe-NHCH2CN (100 mg,
315 lmol), carboxylic acid 13 (90 mg, 347 lmol) and DMF
(10 mL). Column chromatography (MeOH/CH2Cl2 1:99) afforded
the product as white crystals in 29% yield. 1H NMR (400 MHz,
CD3OD) d 7.85 (d, J = 8.7 Hz, 2H), 7.74–7.69 (m, 4H), 7.47 (dd,
J = 2.0, 8.5 Hz, 2H), 7.33–7.19 (m, 5H), 4.82 (ddd, J = 6.3, 7.8,
8.9 Hz, 1H), 4.42 (s, 2H), 4.15 (s, 2H), 3.29–3.05 (m, 2H) ppm. 13C
NMR (75 MHz, CD3OD) d 174.08, 169.84, 145.23, 141.13, 138.34,
137.11, 133.95, 130.34, 130.06, 129.59, 129.17, 128.52, 127.98,
127.91, 117.32, 56.62, 55.20, 38.67 ppm. FTIR = 3426, 3369, 2945,
2090, 1758, 1690, 1640, 1533, 1198, 696 cmꢁ1. HRMS (ESI) m/z
calcd for C25H22N6O2Na (M+Na)+: 461.1702, found 461.1693.
.
1240 cmꢁ1 HRMS (ESI) m/z calcd for C19H19N6O2 (M+H)+:
363.1579, found 363.1570.
4.1.8. 4-(Azidomethyl)benzoyl-Tyr-NHCH2CN (3d)
General procedure 3, using H-Tyr-NHCH2CN (90 mg, 456 lmol)
and DMF (2 mL). Column chromatography (MeOH/CH2Cl2 1:19)
afforded the expected product (86 mg, 50%) as yellow oil.
RF = 0.23 (MeOH/CH2Cl2 1:19). 1H NMR (300 MHz, CD3OD)
d = 7.78 (d, J = 8.1 Hz, 2H), 7.42 (d, J = 8.0 Hz, 2H), 7.11 (d,
J = 8.4 Hz, 2H), 6.73 (d, J = 8.4 Hz, 2H), 4.74 (t, J = 7.5 Hz, 1H), 4.43
(s, 2H), 4.14 (d, J = 2.2 Hz, 2H), 3.17 (dd, J = 13.8, 6.5 Hz, 1H),
3.08–2.92 (m, 1H), 2.85 (s, 1H) ppm. 13C NMR (75 MHz, CD3OD)
d = 174.20, 169.67, 157.36, 141.09, 134.82, 131.32, 129.24,
128.95, 128.81, 117.31, 116.33, 56.87, 54.94, 37.90, 28.00 ppm.
HRMS (ESI) m/z calcd for C19H18N6O3Na (M+Na)+: 401.1338, found
401.1349.
4.1.13. 4-(Azidomethyl)biphenyl-Tyr-NHCH2CN (4c)
General procedure 3, using H-Tyr-NHCH2CN (106 mg,
318 lmol), carboxylic acid 13 (96 mg, 350 lmol) and DMF
(10 mL). Prep-HPLC afforded the product as white crystals in 14%
yield. 1H NMR (400 MHz, CD3OD) d 7.87 (d, J = 8.7 Hz, 2H), 7.75–
7.68 (m, 4H), 7.47 (d, J = 8.4 Hz, 2H), 7.11 (d, J = 8.6 Hz, 2H), 6.72
(d, J = 8.6 Hz, 2H), 4.73 (t, J = 5.9 Hz, 1H), 4.42 (s, 2H), 4.15 (s,
2H), 3.22–2.93 (m, 2H) ppm. 13C NMR (75 MHz, CD3OD) d 174.25,
157.43, 141.14, 137.10, 134.00, 131.35, 130.06, 129.17, 128.87,
128.52, 127.99, 117.32, 116.36, 56.91, 55.20, 37.97, 30.74,
28.01 ppm. FTIR = 3295, 2928, 2450, 2108, 1663, 1621, 1519,
4.1.9. 4-(Azidomethyl)benzoyl-h-Phe-NHCH2CN (3e)
General procedure 3, using H-h-Phe-NHCH2CN (331 mg,
1.00 mmol) and DMF (10 mL). Column chromatography (MeOH/
CH2Cl2 1:39) and recrystallization from EtOAc/Hept afforded the
expected product (200 mg, 53%) as white crystals. Mp = 130–
133 °C. RF = 0.35 (EtOAc/Hept 1:1). 1H NMR (400 MHz, CD3CN)
d = 7.86 (d, J = 8.4 Hz, 2H), 7.46 (d, J = 8.6 Hz, 2H), 7.39 (d,
J = 7.5 Hz, NH), 7.34 (s, NH), 7.31–7.16 (m, 5H), 4.50–4.42 (m,
3H), 4.49 (s, 2H), 4.05 (dd, J = 2.9, 5.8 Hz, 2H), 2.81–2.64 (m, 2H),
2.24–2.02 (m, 2H) ppm. 13C NMR (75 MHz, CD3CN) d = 173.35,
167.96, 142.30, 140.68, 134.65, 129.47, 129.25, 128.91, 127.05,
117.86, 54.67, 54.46, 33.88, 32.72, 28.22 ppm. FTIR = 3266, 2220,
2103, 1671, 1631, 1531, 1497, 1239 cmꢁ1. HRMS (ESI) m/z calcd
for C20H21N6O2 (M+H)+: 377.1726, found 377.1731.
1438, 1256, 1205, 1136 cmꢁ1
25H22N6O3Na (M+Na)+: 477.1651, found 477.1644.
. HRMS (ESI) m/z calcd for
C
4.1.14. N3CH2CO-Leu-Leu-NHCH2CN (5a)
General procedure 3, using H-Leu-Leu-NHCH2CNꢂTFA (30ꢂmg,
105 lmol). The residue was purified by column chromatography
(MeOH/CH2Cl2 1:39) yielding the product (8 mg, 21%) as a slightly
yellow gum. RF = 0.39 (MeOH/CH2Cl2 1:19). 1H NMR (300 MHz,
CD3OD) d 4.37–4.47 (m, 2H) 4.42 (s, 2H), 3.91 (s, 2H), 1.29–1.70
(m, 6H), 0.95 (m, 12H) ppm. 13C NMR (75 MHz, CD3OD) d 174.89,
174.63, 170.45, 117.40, 53.35, 52.88, 52.68, 48.15, 41.70, 41.50,
27.99, 25.86, 21.91, 20.96, 17.62, 16.55 ppm. HRMS (ESI) calcd for
C
16H27N7O3 (M+H)+ 366.2254, found 366.2261.
4.1.10. 4-(Azidomethyl)benzoyl-h-Tyr-NHCH2CN (3f)
4.1.15. N3CH2CO-Leu-Phe-NHCH2CN (5b)
General procedure 3, using H-h-Tyr-NHCH2CN (82 mg,
General procedure 3, using H-Leu-Phe-NHCH2CNꢂTFA (76 mg,
236
l
mol) and DMF (3 mL). Column chromatography (EtOAc/Hept
240 lmol). The residue was purified by column chromatography
1:1–3:1) afforded the expected product (41 mg, 44%) as white crys-
tals. Mp = 48–50 °C. RF = 0.45 (EtOAc/Hept 2:1). 1H NMR (400 MHz,
CD3CN) d 7.86 (d, J = 8.4 Hz, 2H), 7.47 (d, J = 8.6 Hz, 2H), 7.35 (d,
J = 7.7 Hz, NH), 7.32 (d, J = 5.7 Hz, NH), 7.05 (d, J = 8.6 Hz, 2H),
6.72 (d, J = 8.6 Hz, 2H), 4.48 (s, 2H), 4.44 (ddd, J = 4.8, 7.6, 9.4 Hz,
1H), 4.05 (dd, J = 2.8, 5.8 Hz, 2H), 2.72–2.56 (m, 2H), 2.22–1.99
(m, 2H) ppm. 13C NMR (75 MHz, CD3CN) d = 173.45, 167.95,
156.24, 140.67, 134.66, 133.20, 130.48, 129.24, 128.89, 116.18,
54.67, 54.44, 34.13, 31.80, 28.20 ppm. FTIR = 3296, 2976, 2930,
2101, 1639, 1535, 1515, 1244 cmꢁ1. HRMS (ESI) m/z calcd for
(MeOH/CH2Cl2 1:19). The desired product (35 mg, 37% yield) was
obtained as white/yellow crystals. RF = 0.24 (MeOH/CH2Cl2 1:19).
1H NMR (300 MHz, CD3OD) d 7.18–7.30 (m, 5H) 4.56 (t, J = 6 Hz,
1H), 4.36 (t, J = 6 Hz, 1H), 4.09 (s, 2H), 3.87 (s, 2H), 3.16 (dd, J = 9,
15 Hz, 1H), 2.97 (dd, J = 9, 15 Hz, 1H), 1.16–1.51 (m, 3H), 0.90 (m,
6H) ppm. 13C NMR (75 MHz, CD3OD) d 174.31, 173.57, 170.46,
138.08, 130.35, 129.56, 127.87, 117.21, 55.90, 53.38, 52.58, 41.59,
38.41, 27.93, 25.79 ppm. HRMS (ESI) calcd for
C19H25N7O3
(M+H)+ 400.2097, found 400.2118.
C
20H20NaN6O3 (M+Na)+: 415.1495, found 415.1497.
4.1.16. N3CH2CO-Phe-Phe-NHCH2CN (5c)
General procedure 3, using H-Phe-Phe-NHCH2CN (40 mg,
4.1.11. 4-(Azidomethyl)biphenyl-Leu-NHCH2CN (4a)
89 lmol). The residue was purified by preparative HPLC. The
General procedure 3, using H-Leu-NHCH2CN (6.3 mg,
desired product (39 mg, 70% yield) was obtained as white crystals.
RF = 0.30 (MeOH/CH2Cl2 1:19). 1H NMR (400 MHz, CD3CN) d 7.28–
7.14 (m, 10H), 4.56–4.47 (m, 2H), 4.06–3.98 (m, 2H), 3.85 (s, 1H),
37.4
lmol), carboxylic acid 13 (10 mg, 37.4 lmol) and DMF
(1 mL). Prep-HPLC afforded the product as white crystals in 18%