1610
K. H. Yoo et al.
PAPER
6,9-Dichloro-3-isopropyl-4-methylsulfanylisoxazolo[4,5-
c]quinoline (3o)
3-Methylisoxazolo[4,5-c]quinoline (3q)
Yield: 12%; colorless solid; Rf = 0.27 (hexane–EtOAc, 5:1); mp
Yield: 27%; yellow solid; Rf = 0.39 (hexane–EtOAc, 5:1); mp 113–
173–175 °C.
115 °C.
IR (KBr): 3027, 2977, 1850, 1643 cm–1.
1H NMR (200 MHz, CDCl3): d = 9.13 (s, 1 H), 8.07 (t, J = 5.2 Hz,
1 H), 7.52–7.59 (m, 2 H), 7.21–7.28 (m, 2 H), 2.83 (s, 3 H).
13C NMR (75 MHz, DMSO-d6): = 194.5, 189.7, 185.8, 176.7,
144.8, 129.9, 128.6, 125.1, 124.1, 123.6, 25.5.
MS (EI, 70 eV): m/z (%) = 184 (45) [M+], 154 (15), 125 (15), 91
(20), 83 (65), 57 (100).
IR (KBr): 2976, 2930, 2872, 1712, 1618, 1606 cm–1.
1H NMR (500 MHz, CDCl3): d = 8.54 (d, J = 2.4 Hz, 1 H), 7.38 (d,
J = 2.4 Hz, 1 H), 2.98–3.01 (m, 2 H), 2.81 (s, 3 H), 2.36–2.39 (m,
1 H), 1.09 (d, J = 6.5 Hz, 3 H), 1.01 (d, J = 6.5 Hz, 3 H).
13C NMR (125 MHz, CDCl3): d = 167.5, 157.1, 143.72, 134.84,
131.5, 130.4, 129.7, 128.2, 126.6, 126.0, 114.2, 37.3, 27.7, 22.4,
12.1.
HRMS (EI): m/z calcd for C11H8N2O: 184.0636; found: 184.0636.
MS (EI, 70 eV): m/z (%) = 340 (100) [M+], 325 (15), 307 (5), 297
(15), 285 (10), 270 (5).
2, 6,8-Trimethyloxazolo[4,5-c]quinoline (2r)
Yield: 71%; colorless solid; Rf = 0.35 (hexane–EtOAc, 10:1); mp
172–173 °C.
HRMS (EI): m/z calcd for C15H14Cl2N2OS: 340.0203; found:
340.0201.
IR (KBr): 2924, 1898, 1638, 1603 cm–1.
1H NMR (200 MHz, CDCl3): d = 9.07 (s, 1 H), 8.02 (s, 1 H), 7.57
6-Chloro-2-cyclopropyl-4-methylsulfanyl-8-nitrooxazolo[4,5-
c]quinoline (2p)
(s, 1 H), 2.86 (s, 3 H), 2.74 (s, 3 H), 2.60 (s, 3 H).
13C NMR (75 MHz, DMSO-d6): = 153.7, 147.7, 145.6, 142.1,
138.7, 135.6, 133.8, 130.9, 118.6, 115.9, 21.8, 19.1, 10.4.
MS (EI, 70 eV): m/z (%) = 212 (35) [M+], 198 (10), 156 (100), 103
Yield: 67%; colorless solid; Rf = 0.31 (hexane–EtOAc, 5:1); mp
101–102 °C.
IR (KBr): 2923, 2397, 1641, 1604, 1502 cm–1.
1H NMR (500 MHz, CDCl3): d = 7.64 (d, J = 10.0 Hz, 1 H), 7.29 (d,
J = 10.0 Hz, 1 H), 2.74 (s, 3 H), 2.01–2.07 (m, 1 H), 0.96–0.99 (m,
4 H).
13C NMR (125 MHz, CDCl3): d = 164.1, 151.6, 147.8, 143.7, 138.0,
132.7, 123.9, 123.4, 121.4, 120.5, 20.7, 15.7, 11.6.
MS (EI, 70 eV): m/z (%) = 335 (100) [M+], 289 (35), 207 (5), 166
(15), 77 (5).
(25), 96 (15).
HRMS (EI): m/z calcd for C13H12N2O: 212.0949; found: 212.0953.
3,6,8-Trimethylisoxazolo[4,5-c]quinoline (3r)
Yield: 17%; colorless solid; Rf = 0.41 (hexane–EtOAc, 10:1); mp
158–159 °C.
IR (KBr): 2956, 2853, 1782, 1607, 1580, 1502 cm–1.
1H NMR (200 MHz, CDCl3): d = 9.08 (s, 1 H), 8.02 (s, 1 H), 7.57
(s, 1 H), 2.87 (s, 3 H), 2.75 (s, 3 H), 2.60 (s, 3 H).
HRMS (EI): m/z calcd for C14H10ClN3O3S: 335.0131; found:
335.0136.
13C NMR (75 MHz, DMSO-d6): = 155.6, 148.4, 145.8, 143.0,
137.9, 136.0, 133.9, 130.9, 119.1, 116.2, 21.5, 18.9, 10.3.
MS (EI, 70 eV): m/z (%) = 212 (25) [M+], 156 (100), 103 (18), 96
(20), 77 (24).
6-Chloro-3-cyclopropyl-4-methylsulfanyl-8-nitroisoxazolo[4,5-
c]quinoline (3p)
Yield: 27%; colorless solid; Rf = 0.39 (hexane–EtOAc, 5:1); mp
128–129 °C.
IR (KBr): 2923, 2397, 1641, 1604, 1502 cm–1.
HRMS (EI): m/z calcd for C13H12N2O: 212.0949; found: 212.0949.
1H NMR (500 MHz, CDCl3): d = 7.66 (d, J = 10.0 Hz, 1 H), 7.22 (d,
J = 10.0 Hz, 1 H), 2.62 (s, 3 H), 2.02–2.09 (m, 1 H), 0.86–0.89 (m,
4 H).
13C NMR (125 MHz, CDCl3): d = 162.1, 150.4, 146.8, 140.4,
137.9, 132.7, 121.9, 120.4, 118.4, 110.5, 18.7, 10.7, 8.6.
MS (EI, 70 eV): m/z (%) = 335 [M+] (100), 207 (50), 166 (15), 148
(7), 109 (5), 74 (5).
7-Chloro-2-methyloxazolo[4,5-c]quinoline (2s)
Yield: 65%; oil; Rf = 0.38 (hexane–EtOAc, 10:1).
IR (KBr): 3054, 2814, 1745, 1677, 1599 cm–1.
1H NMR (200 MHz, CDCl3): d = 8.10–8.14 (m, 1 H), 7.64–7.69 (m,
2 H), 7.01 (s, 1 H), 2.79 (s, 3 H).
13C NMR (75 MHz, DMSO-d6): d = 176.5, 160.8, 159.7, 150.5,
149.0, 139.7, 137.6, 129.8, 109.3, 100.6, 34.3.
MS (EI, 70 eV): m/z (%) = 218 (100) [M+], 198 (10), 183 (25), 126
HRMS (EI): m/z calcd for C14H10ClN3O3S: 335.0131; found:
335.0134.
(30), 77 (10).
2-Methyloxazolo[4,5-c]quinoline (2q)
Yield: 76%; colorless solid; Rf = 0.21 (hexane–EtOAc, 5:1); mp
185–187 °C.
HRMS (EI): m/z calcd for C11H17ClN2O: 218.0246; found:
218.0244.
IR (KBr): 3075, 2917, 2853, 1926, 1850 cm–1.
7-Chloro-3-methylisoxazolo[4,5-c]quinoline (3s)
Yield: 10%; oil; Rf = 0.42 (hexane–EtOAc, 10:1).
IR (KBr): 3060, 2834, 1711, 1681, 1612 cm–1.
1H NMR (200 MHz, CDCl3): d = 8.06–8.09 (m, 1 H), 7.20–7.29 (m,
2 H), 7.02 (s, 1 H), 2.79 (s, 3 H).
13C NMR (75 MHz, DMSO-d6): = 176.7, 161.3, 159.9, 151.2,
149.7, 139.8, 137.7, 130.5, 111.3, 101.8, 32.7.
MS (EI, 70 eV): m/z (%) = 218 (100) [M+], 177 (15), 126 (25), 109
(5), 77 (15).
1H NMR (200 MHz, CDCl3): d = 9.15 (s, 1 H), 8.39–8.43 (m, 1 H),
8.26 (d, J = 4.4 Hz, 1 H), 7.73 (d, J = 6.8 Hz, 2 H), 7.45 (t,
J = 7.4Hz, 1 H), 2.77 (s, 3 H).
13C NMR (75 MHz, DMSO-d6): = 194.2, 189.2, 184.9, 176.6,
144.6, 129.9, 127.9, 124.5, 123.7, 121.8, 29.8.
MS (EI, 70 eV): m/z (%) = 184 (35) [M+], 149 (55), 111 (30), 97
(55), 57 (100).
HRMS (EI): m/z calcd for C11H8N2O: 184.0636; found: 184.0636.
Synthesis 2006, No. 10, 1599–1612 © Thieme Stuttgart · New York