SHAH ET AL.
5
129.8, 129.7, and 129.3 (Ar–CH), 68.8 (C‐4), 59.7 (C‐6),
54.29 (CH2C6H5), 50.9 (NCH2CH2), 30.2 (NCH2CH2CH2),
21.03 (CH2CH2CH3), 14.0 (CH2CH3); EI‐MS; m/z (rel. int.
%) 247 (M+), 189 (2), 148 (2), 103 (7), 91 (100), 72 (12), 65
(27), and 51 (7); Anal. calcd for C14H20N2S2: C, 60.09; H,
7.14; N, 10.80. Found: C, 60.09; H, 7.12; N, 10.79.
colourless solid, Yield = 77%, m.p = 58‐60°C; UV (meth-
anol) λmax nm: 245, 285; IR (KBr) υmax cm−1: 3300 (OH),
2860 (Aliphatic–C–H), 1480 (C═S); H NMR (CD3OD) δ:
1
4.84 (s, 2H, H‐4), 4.50 (s, 2H, H‐6), 3.90 (t, 2H, J = 7.9 Hz,
NCH2CH2), 3.72 (t, 2H, J = 5.4 Hz, HOCH2CH2), 2.91
(t, 2H, J = 5.4 Hz, NCH2CH2), 1.69‐1.63 (m, 2H,
CH2CH2CH2), 1.40‐1.34 (m, 2H, CH2CH2CH3), 0.96
(t, 3H, J = 7.4 Hz, CH3CH2); 13C NMR (CD3OD + CDCl3)
δ: 193.1(C═S), 71.5 (C‐4), 60.9 (C‐6), 59.5 (CH2OH), 53.5
(NCH2CH2), 53.0 (NCH2CH2OH), 29.6 (NCH2CH2), 20.9
(CH2CH3), 14.1 (CH3CH2); EI‐MS; m/z (rel. Int. %): 234
(M+), 201 (3), 161 (2), 110 (15), 84 (100), 72 (35), and 57
(15); Anal. calcd for C14H18N2O2S2: C, 46.12; H, 7.74; N,
11.95. Found: C, 46.10; H, 7.72; N, 11.94.
4.2.5 | 6‐(5‐Benzyl‐6‐thioxo‐1,3,5‐
thiadiazinan‐3‐yl)hexanoic acid (5)
Benzylamine (2.18 mL, 20 mmol) and 6‐aminocaproic acid
(2.62 g, 20 mmol): recrystallized from ethanol, colourless
solid, Yield = 86%, m.p = 108‐110°C; UV (methanol) λmax
nm: 240, 315; IR (KBr) υmax cm−1: 3400 (COOH), 3020 (Aro-
matic–C–H), 2850 (Aliphatic–C–H), 1729 (C═O), 1460
(C═S); 1H NMR (CD3OD) δ: 7.46‐7.31 (m, 5H, Ar–H), 5.33
(s, 2H, CH2C6H5), 4.47 (s, 2H, H‐4), 4.37 (s, 2H, H‐6), 2.53
(t, 2H, J = 7.3 Hz, CH2CH2N), 2.18 (t, 2H, J = 7.3 Hz,
CH2CH2COOH), 1.47‐1.40 (m, 4H, CH2(CH2)2CH2), 1.18‐
1.10 (m, 2H, CH2CH2CH2); 13C NMR (CD3OD + CDCl3)
δ: 193.0 (C═S), 175.8 (C═O), 135.0 (Ar–C), 128.5, 128.2,
and 127.9 (Ar–CH), 67.6 (C‐4), 58.4 (C‐6), 53.4 (C6H5CH2),
49.7 (NCH2CH2), 33.5 (CH2COOH), 26.4 (NCH2CH2), 25.9
(NCH2CH2CH2), 24.1 (CH2CH2COOH); MS (FAB) m/z:
339; Anal. calcd for C16H22N2O2S2: C, 56.77; H, 6.55; N,
8.28. Found: C, 56.76; H, 6.55; N,8.27.
4.2.8 | 3‐Butyl‐5‐pyrimidin‐2‐yl‐1,3,5‐
thiadiazinane‐2‐thione (8)
n‐Butylamine (1.97 mL, 20 mmol) and 2‐aminopyrimidine
(1.90 g, 20 mmol): recrystallized from ethanol, colourless
solid, Yield = 70%, m.p = 99‐101°C; UV (methanol) λmax
nm: 275; IR (KBr) υmax cm−1: 2873 (Aliphatic–C–H), 1465
1
(C═S); H NMR (CD3OD) δ: 8.33 (d, 2H, J = 3.7 Hz,
Ar–CH), 6.74 (t, 1H, J = 4.7 Hz, Ar–H), 5.27 (s, 2H, H‐4),
4.84 (s, 2H, H‐6), 3.65 (t, 2H, J = 7.2 Hz, NCH2CH2),
1.63‐1.56 (m, 2H, CH2CH2CH2), 1.38‐1.31 (m, 2H,
CH3CH2CH2), 0.92 (t, 3H, J = 7.3 Hz, CH3CH2);13C NMR
(CD3OD) δ: 198.3 (C═S), 162.4 (Ar‐C), 159.4 (Ar–C),
113.0 (Ar–CH), 49.0 (C‐4), 48.3 (NCH2CH2), 47.7 (C‐6),
31.1 (CH2CH2CH2), 21.1 (CH3CH2CH2), 14.0 (CH3CH2);
MS (FAB) m/z: 286; Anal. Calcd for C11H16N4S2: C, 49.20;
H, 5.97; N, 20.89. Found: C, 49.19; H, 5.95; N, 20.86.
4.2.6 | (5‐Butyl‐6‐thioxo‐1,3,5‐thiadiazinan‐
3‐yl)acetic acid (6)
n‐Butylamine (1.97 mL, 20 mmol) and glycine (1.5 g,
20 mmol): recrystallized from ethanol, colourless solid,[21]
Yield = 80%, m.p = 97‐99°C; UV (methanol) λmax nm:
210, 285: IR (KBr): 3420 (COOH), 2954 (Aliphatic–C–
4.2.9 | 6‐(5‐Butyl‐6‐thioxo‐1,3,5‐
thiadiazinan‐3‐yl)hexanoic acid (9)
1
H), 1733 (C═O), 1508 (C═S); H NMR (CD3OD) δ: 4.53
(s, 2H, H‐4), 4.52 (s, 2H, H‐6), 3.97 (t, 2H, J = 7.8 Hz,
NCH2CH2), 3.30 (s, 2H, CH2COOH), 1.67‐1.61 (m, 2H,
CH2CH2CH2), 1.38‐1.33 (m, 2H, CH2CH2CH3), 0.96
(t, J = 7.3 Hz, 3H, CH2CH3); 13C NMR (CD3OD) δ:
192.8 (C═S), 172.8 (C═O), 70.9 (C‐4), 59.4 (C‐6), 52.9
(CH2COOH), 52.0 (CH2CH2N), 29.5 (CH2CH2CH2), 20.9
(CH2CH2CH3), 14.1 (CH3CH2); EI‐MS; m/z (rel. int. %)
248 (M+), 115 (22), 84 (86), 72 (96), 60 (58), and 57
(100); Anal. calcd for C9H16N2O2S2: C, 43.54; H, 6.45; N,
11.29. Found: C, 43.52; H, 6.42; N, 11.28.
n‐Butylamine (1.97 mL, 20 mmol) and 6‐amino caproic
acid (2.62 g, 20 mmol): recrystallized from ethanol,
colourless solid, Yield = 82%, m.p = 88‐90°C; UV (metha-
nol) λmax nm: 250, 285; IR (KBr) υmax cm−1: 3400 (COOH),
2865 (Aliphatic–C–H), 1695 (C═O), 1503 (C═S); 1H NMR
(CD3OD) δ: 4.47 (s, 2H, H‐4), 4.46 (s, 2H, H‐6), 3.80
(t, 2H, J = 7.9 Hz, NCH2CH2), 2.78 (t, 2H, J = 7.1 Hz,
NCH2CH2), 2.29 (t, 2H, J = 7.3 Hz, CH2CH2COOH), 1.68‐
1.62 (m, 4H, CH2(CH2)2CH2), 1.61‐1.55 (m, 2H,
CH2CH2CH2), 1.44‐1.40 (m, 2H, CH3CH2CH2), 1.39‐1.34
(m, 2H, CH2CH2CH2), 0.96 (t, 3H, J = 7.3 Hz, CH3CH2);
13C NMR (CD3OD) δ: 193.0 (C═S), 177.4 (C═O), 71.0
(C‐4), 58.8 (C‐6), 52.9 (NCH2), 50.9 (NCH2), 34.8
(CH2COOH), 29.5 (CH2CH2CH2), 28.1 (CH2CH2CH2),
27.5 (CH2CH2COOH), 25.3 (CH2CH2CH2), 20.9
(CH2CH2CH3), 14.1 (CH3CH2); EI‐MS; m/z (rel. int. %):
4.2.7 | 3‐Butyl‐5‐(2‐hydroxyethyl)‐1,3,5‐
thiadiazinane‐2‐thione (7)
n‐Butylamine (1.97 mL, 20 mmol) and ethanolamine
(1.20 mL, 20 mmol): recrystallized from ethanol,