2520
HETEROCYCLES, Vol. 81, No. 11, 2010
To a stirred solution of 10H-2,7-diazaphenothiazine (1) (100 mg, 0.5 mmol) in dry EtOH (5 mL) at rt,
butyl iodide (0.18 mL, 1.6 mmol) was added and the reaction mixture was refluxed for 24 h. The solvent
was distilled off, the residue was dissolved in a mixture CHCl
3
-EtOH (1:1) and purified by column
chromatography (aluminum oxide, CHCl -EtOH 1:1) to give:
3
1
1
. 2,7-Dibutyl-2,7-diazaphenothiazidiinium diiodide (7) (80 mg, 30%), mp 210-212 °C (EtOH). H NMR
(DMSO-d
6
) #: 0.89 (m, 6$, 2C$
3
2 2
), 1.28 (m, 4H, 2CH ), 1.76 (m, 4H, 2CH ), 4.12 (t, 2H, J = 7.0 Hz,
NCH
2
), 4.32 (t, 2H, J = 7.0 Hz, NCH
2
), 6.81 (d, 1H, J = 6.0 Hz, H4 or H9), 7.73 (d, 1H, J = 6.0 Hz, H4
or H9), 7.75 (s, 1H, H1 or H6), 8.25 (d, 1H, J = 6.0 Hz, H3 or H8), 8.38 (d, 1H, J = 6.0 Hz, H3 or H8),
.39 (s, 1H, H1 or H6), 11.01 broad s, 1H, NH).
FAB MS m/z: 314 (M+1–2HI, 100), 258 (M+1–HI and C
8
4
H
9
25 2 3
I, 88). Anal. Calcd for C18H I N S: C,
3
2
#
6
7
7.98; H, 4.43; N, 7.38. Found C, 37.75; H, 4.33; N, 7.29.
1
. 7-Butyl-2,7-diazaphenothiazine (11) (20 mg, 29%), mp 62-63 °C (EtOH). H NMR (CDCl
3
)
: #: 0.97 (t, J = 6.8 Hz, 3H, CH ), 1.33 (m, 2H, CH ), 1.71 (m, 2H, CH ), 3.68 (t, J = 6.8 Hz, 2H, NCH ),
3
2
2
2
.44 (d, J = 4.9 Hz, 1H, H4), 6.48 (d, J = 6.0 Hz, 1H, H9), 6.61 (s, 1H, H6), 7.13 (d, J = 4.9 Hz, 1H, H3),
.85 (d, J = 6.0 Hz, 1H, H8), 7.98 (s, 1H, H1). EI MS m/z: 257 (M, 100), 201 (M–C , 74). Anal. Calcd
S: C, 65.34; H, 5.87; N, 16.33. Found C, 65.13; H, 5.71; N, 16.16.
4
H
8
15 3
for C14H N
Synthesis of 2,7-dibenzyl-2,7-diazaphenothiazidiinium dichloride (8) and 7-benzyl-2,7-diazapheno-
thiazine (12)
To a stirred solution of 10H-2,7-diazaphenothiazine (1) (100 mg, 0.5 mmol) in dry EtOH (5 mL) at rt,
benzyl chloride (0.15 mL, 1.5 mmol) was added and the reaction mixture was refluxed for 48 h. After
cooling the resulted solid was filtered off to give 2,7-dibenzyl-2,7-diazaphenothiazidiinium dichloride (8)
1
(
90 mg, 40%), mp 211-212 °C (EtOH). H NMR (DMSO-d
6
2 2
) #: 5.32 (s, 2H, CH ), 5.56 (s, 2H, CH ),
6
.87 (d, J = 5.0 Hz, 1H, H4 or H9), 7.42-7.45 (m, 10H, 2C
6
H
5
), 7.67 (d, J = 5.0 Hz, 1H, H4 or H9), 7.95
(
s, 1H, H1 or H6), 8.32 (d, J = 5.0 Hz, 1H, H3 or H8), 8.45 (s, 1H, H1 or H6), 8.49 (d, J = 5.0 Hz, 1H, H3
or H8), 11.08 (s, 1H, NH). FAB MS m/z: 382 (M+1–2HCl, 68), 292 (M+1–HCl and C CH Cl, 42),
S: C, 63.43; H, 4.66; N, 9.25. Found C, 63.22; H, 4.57; N,
6
H
5
2
1
85 (2gly+1, 100). Anal. Calcd for C24
.02.
2 3
H21Cl N
9
3
The filtrate was concentrated and purified by column chromatography (aluminum oxide, CHCl -EtOH
1
1
0:1) to give 7-benzyl-2,7-diazaphenothiazine (12) (37 mg, 37%); 59-61 °C (EtOH). H NMR (CDCl
3
)
#
: 5.28 (s, 2H, CH
), 7.47 (d, J = 6.1 Hz, 1H, H9), 8.01 (m, 2H, H3 and H8), 8.35 (s, 1H, H1). FAB MS m/z: 292 (M+1,
00), 201 (M+1–CH C H , 28). Anal. Calcd for C H N S: C, 70.08; H, 4.50; N, 14.42. Found C, 69.88;
2 6 2
), 6.58 (d, J = 5.0 Hz, 1H, H4), 7.22 (s, 1H, H6), 7.33 (m, 2H, C H ), 7.45 (m, 2H,
6 3
C H
1
2
6
5
17 13
3
H, 4.32; N, 14.23.
Synthesis of 7-alkyl-2,7-diazaphenothiazines (9) and (12) from 2,7-dialkyl-2,7-diazaphenothiazi-
diinium dihalides (5) and (8)
To a solution of 2,7-dialkyl-2,7-diazaphenothiazidiinium dihalides (5) or (8) (0.2 mmol) in water (2 mL).