Molecules 2013, 18
15408
13
2H), 1.54–1.42 (m, 3H), 0.82 (d, J = 5.5 Hz, 6H); C-NMR (CDCl3) δ 172.3, 170.2, 162.9, 147.4,
144.2, 144.1, 142.7, 136.2, 129.3, 128.5, 126.9, 54.4, 52.2, 50.9, 41.2, 38.4, 24.7, 22.5, 21.8 [11].
N-((S)-1-(((S)-1-Hydroxy-4-methylpentan-2-yl)amino)-1-oxo-3-phenylpropan-2-yl)pyrazine-2-carboxa
1
mide (12): H-NMR (CDCl3) δ 9.29 (d, J = 1.5 Hz, 1H), 8.71 (d, J = 2.4 Hz, 1H), 8.50 (d,
J = 2.4 Hz, 1H), 8.42 (d, J = 8.1 Hz, 1H), 7.28–7.15 (m, 5H), 6.10 (br, 1H), 4.83 (m, 1H), 3.88
(m, 1H), 3.91-3.31 (m, 2H), 3.24–3.06 (m, 2H), 2.30–2.00 (br, 2H), 1.45–1.38 (m, 1H), 1.41 (dd,
J = 6.3 Hz, J = 6.3 Hz, 2H), 0.75 (dd, J = 6.3 Hz, J = 1.9 Hz, 6H); 13C-NMR (CDCl3) δ 170.4, 163.0,
147.5, 144.2, 143.9, 142.8, 136.5, 129.4, 128.7, 127.1, 65.1, 55.0, 50.0, 39.7, 38.8, 24.6, 22.8, 22.1;
HRMS (ESI) [M−H]− calcd for C20H25N4O3 369.1927, found 369.1922.
(S)-N-(1-Oxo-3-phenyl-1-((3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)propyl)amino)propan-2-yl)
1
pyrazine-2-carboxamide (14): H-NMR (CDCl3) δ 9.30 (s, 1H), 8.70 (s, 1H), 8.51 (s, 1H), 8.41 (m,
1H), 7.28–7.18 (m, 5H), 4.76–4.70 (m, 1H), 3.22–3.07 (m, 4H), 1.50–1.43 (m, 2H), 1.19 (s, 12H),
0.84–0.77 (m, 2H); 13C-NMR (CDCl3) δ 169.9, 162.7, 147.3, 144.0, 142.7, 136.5, 129.2, 128.6, 126.9,
83.1, 54.9, 41.5, 38.8, 29.6, 24.7, 23.4, 14.1; HRMS (ESI) [M+Na]+ calcd for C23H31BN4O4Na
461.2336, found 461.2331.
N-(2-(((R)-3-methyl-1-((3aR,4R,6R,7aS)-5,5,7a-trimethylhexahydro-4,6-methanobenzo[d][1,3,2]dioxa
1
borol-2-yl)butyl)amino)-2-oxoethyl)pyrazine-2-carboxamide (15): H-NMR (CDCl3) δ 9.33 (s, 1H),
8.68 (s, 1H), 8.49 (s, 1H), 7.85 (br, s, 1H), 4.33 (d, 2H), 3.98–3.92 (m, 2H), 2.82–2.92 (m, 1H),
2.43–2.35 (m, 1H), 2.28–2.22 (m, 1H), 2.13 (t, J = 5.4 Hz, 1H), 1.91–1.80 (m, 2H), 1.56–1.47 (m, 1H),
1.43 (s,3H). 1.35 (d, J = 10.7 Hz, 1H), 1.47–1.31 (m, 2H), 1.28 (s, 3H), 0.86 (s, 3H), 0.85 (d, J = 5.0 Hz,
3H), 0.84 (d, J = 5.0 Hz, 3H); 13C-NMR (CDCl3) δ 171.0, 162.7, 147.0, 144.3, 142.6, 86.2, 78.0, 53.9,
51.2, 40.5, 40.1, 39.5, 38.9, 38.4, 35.7, 29.2, 27.8, 27.0, 25.6, 24.4, 23.3, 22.3.
N-((S)-1-(((R)-3-Methyl-1-((3aR,4R,6R,7aS)-5,5,7a-trimethylhexahydro-4,6-methanobenzo[d][1,3,2]di
oxaborol-2-yl)butyl)amino)-1-oxo-3-phenylpropan-2-yl)benzamide (16): 1H-NMR (CDCl3) δ 7.71–7.70 (d,
2H), 7.48–7.45 (d, 2H), 7.26–7.20 (m, 6H), 4.84–4.75 (m, 1H), 4.30–4.27 (d, J = 6.9 Hz, 1H),
3.17–3.08 (m, 3H), 2.33–2.25 (m, 1H), 2.18–2.12 (m, 1H), 2.03 (t, J = 5.4 Hz, 1H), 1.91–1.80 (m, 2H),
1.56–1.47 (m, 1H), 1.43 (s,3H). 1.35 (d, J = 10.7 Hz, 1H), 1.47–1.31 (m, 2H), 1.28 (s, 3H), 0.86 (s,
3H), 0.85 (d, J = 5.0 Hz, 3H), 0.84 (d, J = 5.0 Hz, 3H); 13C-NMR (CDCl3) δ 170.4, 162.8, 137.2, 133.9,
131.6, 129.4, 128.5, 128.4, 127.1, 126.7, 55.2, 37.5, HRMS (FAB) [M+H]+ calcd for C31H42O4N2B
517.3238, found 517.3232.
(S)-2-Acetamido-N-((R)-3-methyl-1-((3aR,4R,6R,7aS)-5,5,7a-trimethylhexahydro-4,6-methanobenzo[d
1
][1,3,2]dioxaborol-2-yl)butyl)-3-phenylpropanamide (17): H-NMR (CDCl3) δ 7.24–7.16 (m, 5H),
4.58–4.63 (m, 1H), 4.21–4.20 (d, J = 5.1 Hz, 1H), 3.05–2.98 (m, 3H), 2.33–2.25 (m, 1H), 2.18–2.12
(m, 1H), 2.03 (t, J = 5.4 Hz, 1H), 1.97 (s,3H) 1.80–1.91 (m, 2H), 1.47–1.56 (m, 1H), 1.43 (s,3H). 1.35
(d, J = 10.7 Hz, 1H), 1.31–1.47 (m, 2H), 1.28 (s, 3H), 0.86 (s, 3H), 0.85 (d, J = 5.0 Hz, 3H), 0.84 (d,
J = 5.0 Hz, 3H); 13C-NMR (CDCl3) δ 171.3, 169.9, 136.6, 129.3, 128.4, 126.7, 85.5, 77.6, 53.8, 51.3,