Costa et al.
7.24 (m, 3 H, 2 H), 6.12 (dq, J ) 15.5, 1.6 Hz, 1 H), 5.72 (s, 1
H, dCHCO2Me), 3.81 (s, 3 H), 2.38 (dd, J ) 6.8, 1.6 Hz, 3 H)
(the Z stereochemistry of the methoxycarbonylmethylene
moiety was confirmed by a 2D NOESY experiment); 13C NMR
(CDCl3) δC 165.9, 156.3, 154.1, 142.1, 140.2, 133.1, 127.3, 126.9,
123.0, 122.5, 118.4, 89.3, 50.9, 18.7; MS m/z 243 (M+, 100),
228 (7), 212 (24), 198 (22), 184 (93), 156 (20), 154 (21), 129
(22), 115 (12), 89 (17), 76 (11), 69 (20), 59 (7). Anal. Calcd for
aromatic), 7.36 (td, J ) 7.4, 1.3 Hz, 1H), 7.07 (d, J ) 7.4 Hz,
1 H), 6.99 (td, J ) 8.0, 1.2 Hz, 1 H), 5.68 (s, 1 H dCHCO2Me),
5.64 (bs, 1 H), 3.71 (s, 3 H), 3.39 (t, J ) 7.1 Hz, 2 H), 1.70-
1.55 (m, 2 H), 0.96 (t, J ) 7.4 Hz, 3 H); (the Z stereochemistry
of the methoxycarbonylmethylene moiety was confirmed by a
2D NOESY experiment); 13C NMR (CDCl3) δC 165.4, 158.0,
151.6, 144.1, 133.3, 124.1, 123.2, 123.1, 115.2, 88.3, 50.8, 43.1,
22.7, 11.3; MS m/z 260 (M+, 72), 218 (16), 201 (19), 186 (100),
160 (18), 144 (27), 90 (14), 59 (6). Anal. Calcd for C14H16N2O3:
C, 64.59; H, 6.20; N, 10.77. Found: C, 64.52; H, 6.17; N,10.74.
C
14H13NO3: C, 69.11; H, 5.39; N, 5.76. Found: C, 69.06; H,
5.36; N, 5.72.
(E,E)-(2-P r op en ylb en zo[d ][1,3]oxa zin -4-ylid en e)a ce-
tic a cid m eth yl ester 3m -(E) ≡ 3o-(E): orange solid; mp 84-
86 °C; IR (KBr) νmax cm-1 2949 (w), 1713 (s), 1683 (s), 1626
(s), 1601 (s), 1471 (m), 1431 (s), 1272 (s), 1143 (m), 1083 (s),
(Z)-(2-Oxo-3-p r op yl-2,3-d ih yd r o-1H -q u in a zolin -4-yli-
d en e)a cetic a cid m eth yl ester 5r -(Z): yellow ochre solid;
mp 162-165 °C; IR (KBr) νmax cm-1 3325 (m), 3058 (w), 2945
(w), 1704 (s), 1690 (s), 1602 (s), 1576 (s), 1153 (s), 1075 (m),
1
1
974 (m), 806 (m), 763 (m); H NMR (CDCl3) δH 8.86 (dd, J )
799 (m), 755 (m); H NMR (CDCl3) δH 9.05 (bs, 1 H), 7.57 (d,
8.5, 1.1 Hz, 1 H), 7.78 (dd, J ) 8.1, 1.4 Hz, 1 H), 7.33-7.24
(m, 2 H, 1 H), 7.10 (td, J ) 8.5, 1.4 Hz, 1 H), 5.99 (dq, J )
15.4, 1.4 Hz, 1 H), 5.71 (s, 1 H), 3.78 (s, 3 H), 1.94 (dd, J )
6.8, 1.4 Hz, 3 H); 13C NMR (CDCl3) δC 167.5, 156.6, 141.5,
135.8, 131.1, 126.6, 126.9, 122.5, 122.3, 121.0, 120.6, 97.1, 52.5,
17.8; MS m/z 243 (M+, 89), 228 (12), 212 (28), 198 (23), 184
(100), 156 (25), 154 (22), 129 (25), 89 (19), 69 (24), 59 (11).
Anal. Calcd for C14H13NO3: C, 69.11; H, 5.39; N, 5.76. Found:
C, 69.05; H, 5.35; N, 5.72.
J ) 7.5 Hz, 1 H aromatic), 7.35-7.31 (m, 1 H), 7.07 (td, J )
7.5, 1.1 Hz, 1 H), 6.90 (dd, J ) 7.9, 0.9 Hz, 1 H), 5.74 (s, 1 H
dCHCO2Me), 4.13 (t, J ) 7.1 Hz, 2 H), 3.76 (s, 3 H), 1.64-
1.54 (m, 2 H), 0.79 (t, J ) 7.4 Hz, 3 H); (the Z stereochemistry
of the methoxycarbonylmethylene moiety was confirmed by a
2D NOESY experiment); 13C NMR (CDCl3) δC 165.5, 152.0,
147.1, 135.6, 131.1, 128.5, 126.3, 123.4, 114.7, 96.0, 50.5, 47.1,
20.5, 11.0; MS m/z 260 (M+, 28), 229 (15), 218 (74), 201 (26),
187 (100), 160 (40), 145 (15), 131 (15), 116 (20). Anal. Calcd
for C14H16N2O3: C, 64.59; H, 6.20; N, 10.77. Found: C, 64.51;
H, 6.15; N, 10.73.
(E)-(2-Oxo-3-p r op yl-2,3-d ih yd r o-1H -q u in a zolin -4-yli-
d en e)a cetic a cid m eth yl ester 5r -(E): yellow ochre solid;
mp 126-128 °C; IR (KBr) νmax cm-1 3321 (m), 3051 (w), 2955
(w), 1702 (s), 1690 (s), 1602 (s), 1576 (s), 1153 (s), 1075 (m),
799 (m), 755 (m); 1H NMR (CDCl3) δH 8.92 (bs, 1 H), 8.08 (dd,
J ) 8.1, 1.1 Hz, 1 H), 7.38 (td, J ) 8.1, 1.3 Hz, 1 H), 7.06 (td,
J ) 8.0, 1.1 Hz, 1 H), 6.87 (dd, J ) 8.0, 1.3 Hz, 1 H), 5.40 (s,
1 H), 3.89 (t, J ) 7.4 Hz, 2 H), 3.73 (s, 3 H), 1.83-1.72 (m, 2
H), 0.99 (t, J ) 7.4 Hz, 3 H); 13C NMR (CDCl3) δC 167.6, 150.9,
148.4, 136.3, 132.1, 130.1, 127.6, 121.7, 114.1, 94.6, 51.2, 45.8,
19.1, 11.2; MS m/z 260 (M+, 25), 229 (17), 218 (77), 201 (22),
187 (100), 160 (43), 145 (12), 131 (11), 116 (22). Anal. Calcd
for C14H16N2O3: C, 64.59; H, 6.20; N, 10.77. Found: C, 64.55;
H, 6.16; N,10.74.
(E,Z)-(2-Styr ylben zo[d][1,3]oxazin -4-yliden e)acetic acid
m eth yl ester 3n -(Z): orange solid; mp 113-115 °C; IR (KBr)
ν
max cm-1 2949 (w), 1699 (s), 1645 (s), 1622 (m), 1581 (s), 1465
(m), 1433 (m), 1278 (s), 1260 (m), 1202 (w), 1063 (s), 971 (s),
761 (s), 694 (m); 1H NMR (CDCl3) δH 8.03 (d, J 16.0 Hz, 1 H),
7.58-7.50 (m, 3 H aromatic), 7.43 (t, J 7.4 Hz, 1 H), 7.39-
7.29 (m, 4 H), 7.30 (t, J 7.3 Hz, 1 H), 6.68 (d, J 16.0 Hz, 1 H),
5.69 (s, 1 H, dCHCO2Me), 3.76 (s, 3 H) (the Z stereochemistry
of the methoxycarbonylmethylene moiety was confirmed by a
2D NOESY experiment); 13C NMR (CDCl3) δC 164.8, 156.0,
154.3, 141.8, 140.5, 135.0, 132.8, 129.7, 128.6, 127.9, 127.6,
126.9, 122.8, 118.9, 118.3, 89.5, 50.8; MS m/z 305 (M+, 100),
276 (12), 246 (90), 232 (14), 217 (71), 204 (22), 152 (11), 136
(21), 115 (27), 102 (36), 89 (15), 77 (18), 51 (9). Anal. Calcd for
C
19H15NO3: C, 74.73; H, 4.95; N, 4.59. Found: C, 74.68; H,
4.91; N, 4.55.
(E,E)-(2-Styr ylben zo[d][1,3]oxazin -4-yliden e)acetic acid
m eth yl ester 3n -(E): orange solid; mp 95-97 °C; IR (KBr)
4-Oxo-2-p r op yla m in o-4H -q u in olin e-3,3-d ica r b oxylic
a cid d im eth yl ester (6r ): white solid; 177-179 °C; νmax(KBr)/
cm-1 3251 (m), 3094 (w), 2956 (w), 1731 (s), 1686 (s), 1661 (s),
1601 (m), 1475 (s), 1327 (s), 1162 (m), 1232 (s), 1071 (m), 811
(m), 756 (m); δH (CDCl3) 7.90 (dd, J ) 7.7, 1.6 Hz, 1 H), 7.54
(td, J ) 8.0, 1.6 Hz, 1 H), 7.23 (dd, J ) 8.0, 1.0 Hz, 1 H), 7.07
(td, J ) 7.7, 1.0 Hz, 1 H), 5.41 (bs, 1 H), 3.77 (s, 6 H, 2), 3.24
(t, J ) 8.4 Hz, 2 H), 1.70-1.58 (m, 2 H), 0.95 (t, J ) 7.5 Hz, 3
H); 13C NMR (CDCl3) δC 196.4, 164.8, 153.8, 151.2, 142.9,
137.1, 127.0, 126.5, 123.6, 67.6, 53.9, 43.4, 22.0, 11.2; MS m/z
318 (M+, 27), 276 (11), 259 (12), 244 (96), 227 (100), 213 (11),
199 (28), 186 (37), 171 (15), 145 (14), 119 (13), 59 (8). Anal.
Calcd for C16H18N2O5: C, 60.35; H, 5.70; N, 8.80. Found: C,
60.30; H, 5.66; N, 8.76.
ν
max cm-1 2949 (w), 1698 (s), 1644 (s), 1622 (m), 1580 (s), 1465
(m), 1433 (m), 1278 (s), 1259 (m), 1202 (w), 1063 (s), 971 (s),
761 (s), 694 (m); 1H NMR (CDCl3) δH 9.01 (dd, J ) 7.9, 0.9 Hz,
1 H), 7.81 (dd, J ) 8.0, 1.1 Hz, 1 H), 7.74 (d, J ) 15.6 Hz, 1
H), 7.60 (t, J ) 8.0 Hz, 1 H), 7.58-7.55 (m, 2 H), 7.39-7.36
(m, 3 H), 7.15 (t, J ) 7.9 Hz, 1 H), 6.59 (d, J ) 15.6 Hz, 1 H),
5.75 (s, 1 H), 3.72 (s, 3 H); 13C NMR (CDCl3) δC 166.4, 158.1,
154.9, 141.6, 139.9, 134.7, 133.3, 129.4, 128.6, 127.8, 127.6,
126.1, 122.9, 118.8, 118.2, 97.3, 51.2; MS m/z 305 (M+, 100),
276 (15), 246 (90), 232 (16), 217 (71), 204 (22), 152 (15), 136
(27), 115 (33), 102 (42), 89 (20), 77 (24), 51 (9). Anal. Calcd for
C
19H15NO3: C, 74.73; H, 4.95; N, 4.59. Found: C, 74.67; H,
4.91; N, 4.54.
2-Meth oxyca r bon yla m in o-4-oxo-1,4-d ih yd r oqu in olin e-
3-ca r boxylic a cid m eth yl ester (7s): white solid; 191-193
°C; νmax(KBr)/cm-1 3502 (m), 3217 (m), 2951 (w), 1723 (s), 1662
(s), 1620 (s), 1581 (s), 1557 (s), 1448 (s), 1399 (s), 1325 (m),
1292 (s), 1232 (s), 1036 (s), 774 (s); δH (CDCl3) 12.34 (sb, 1 H),
11.86 (bs, 1 H), 8.34 (d, J ) 8.0 Hz, 1 H), 7.58 (td, J ) 8.1, 1.3
Hz, 1 H), 7.34 (td, J ) 8.0 , 0.9 Hz, 1 H), 7.24 (d, J ) 8.1 Hz,
1 H), 3.94 (s, 3 H), 3.90 (s, 3 H); 13C NMR (CDCl3) δC 190.3,
174.8, 170.3, 155.1, 151.8, 135.3, 132.6, 126.9, 125.4, 124.8,
116.9, 53.6, 52.1; MS (EI) m/z 276 (M+, absent), 244 (100), 229
(10), 215 (20), 167 (56), 166 (47), 165 (81), 152 (18); (ES) m/z
277 (M + 1), 263, 245. Anal. Calcd for C13H12N2O5: C, 56.51;
H, 4.38; N, 10.14. Found: C, 56.46; H, 4.36; N, 10.10.
(2-ter t-Bu toxyca r bon yla m in op h en yl)p r op yn oic a cid
m eth yl ester : white solid; 84-86 °C; νmax(KBr)/cm-1 3407 (s),
2970 (m), 2210 (w) 1734 (s), 1717 (s), 1707 (s), 1577 (m), 1521
(s), 1452 (s), 1301 (m), 1152 (m); 1H NMR (CDCl3) δH (CDCl3)
8.19 (d, J ) 8.5 Hz, 1 H), 7.49 (dd, J ) 8.5, 1.3 Hz, 1 H), 7.42
(td, J ) 8.5, 1.3 Hz, 1 H), 7.16 (bs, 1 H) 7.00 (td, J ) 8.5, 0.8
Hz, 1 H), 3.86 (s, 3 H), 1.54 (s, 9 H); 13C NMR (CDCl3) δC 154.0,
152.1, 141.5, 133.4, 132.2, 122.2, 118.1, 107.2, 86.8, 82.1, 81.3,
52.8, 28.2; MS m/z 275 (M+, 12), 219 (11), 175 (95), 170 (31),
143 (65), 115 (28), 89 (12), 59 (7), 57 (100). Anal. Calcd for
C
15H17NO4: C, 65.43; H, 6.23; N, 5.09. Found: C, 65.38; H,
6.20; N, 5.05.
(Z)-(2-P r op yla m in oben zo[d ][1,3]oxa zin -4-ylid en e)a ce-
tic a cid m eth yl ester 4r -(Z): yellow orange solid; mp 71-73
°C; IR (KBr) νmax cm-1 3273 (m), 3094 (w), 2956 (w), 1707 (s),
1665 (s), 1607 (s), 1591 (s), 1168 (s), 1063 (m), 810 (m), 757
(m); 1H NMR (CDCl3) δH 7.47 (dd, J ) 8.0, 1.3 Hz, 1 H
(Z)-(2-Ben zyla m in oben zo[d ][1,3]oxa zin -4-ylid en e)a ce-
tic a cid m eth yl ester 4t-(Z): pale yellow solid; mp 139-141
°C; IR (KBr) νmax cm-1 2934 (w), 1719 (s), 1685 (s), 1604 (m),
1472 (m), 1244 (m), 1150 (s), 1087 (m), 803 (m), 751 (m), 737
(m); 1H NMR (CDCl3) δH 7.48 (dd, J ) 8.1, 1.4 Hz, 1 H
2476 J . Org. Chem., Vol. 69, No. 7, 2004