Synthesis of 1,2,4-triazolo[1,5-d]-1,2,4-triazine-5-thiones

Article abstract of DOI:10.1002/jhet.5570420544

In an attempt to discover bicyclic compounds containing the 1,2,4-triazine moiety, 1,2,4-triazolo[1,5-d]-1,2,4-triazine-5-thiones from one pot reaction of arylnitriles with 4-amino-1,2,4-triazine-3-thione-5-one in the presence of potassium tert-butoxide were synthesized.

Full text of DOI:10.1002/jhet.5570420544

Jul-Aug 2005
1021
Synthesis of 1,2,4-Triazolo[1,5-d]-1,2,4-triazine-5-thiones
a,c,
a
a
Majid M. Heravi *, Naser Montazeri , Mohammad Rahimizadeh ,
a
d
Mehdi Bakavoli and Mitra Ghassemzadeh
a
Department of Chemistry, School of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran;
b
Department of Chemistry, Azad University, Tonekabon, Iran;
Department of Chemistry, School of Sciences, Azzahra University, Vanak, Tehran, Iran;
c
d
Chemistry & Chemical Engineering Research Center of Iran, Tehran, Iran
Received December 20, 2004
In an attempt to discover bicyclic compounds containing the 1,2,4-triazine moiety, 1,2,4-triazolo[1,5-d]-
1,2,4-triazine-5-thiones from one pot reaction of arylnitriles with 4-amino-1,2,4-triazine-3-thione-5-one in
the presence of potassium tert-butoxide were synthesized.
J. Heterocyclic Chem., 42, 1021 (2005).
Introduction.
that the product should be 8-methyl-2-phenyl-6H-1,2,4-tri-
azolo-[1,5-d]-1,2,4-triazine-5-thione (4, Ar = Ph).
The 1,2,4-triazine ring system is a key component of
commercial dyes, herbicides, insecticides and more
recently pharmaceutical compositions [1]. Lamotrigine, a
sodium channel blocker is the active component of
Lamictal, which is in clinical use as an anticonvulsant ther-
apy, contains the 1,2,4-triazine ring [2].
In continuation of our earlier studies on the orientation
of cyclization in bicyclic compounds derived from 1,2,4-
triazine [3], we now report, in this communication our
work on the synthesis of a novel heterocyclic system 1,2,4-
triazolo-[1,5-d]-1,2,4-triazine-5-thiones.
To the best of our knowledge the only 1,2,4-triazolo[1,5-
d]1,2,4-triazine 2 has been synthesized through compli-
cated reaction of 5-hydrazino-1,2,4-triazine 1 with triethyl
ortho acetate and subsequent heating in concentrated acid
[4] (Scheme 1)
Mechanistically, the formation of 4 could be
explained as shown in Scheme 2. Most probably a two
step process occurs: first a standard condensation of the
amino group with nitrile and the known intramolecular
cyclization of nucleophilic the nitrogen moiety to the
carbonyl group followed by elimination of water. The
unexpected feature of this reaction is selective and pre-
ferred attack of nucleophilic nitrogen to the carbonyl
group of triazine at the 5 position instead of thione
group at the 3 position to afford the expected, 1,2,4-tri-
azolo[5,1-c]-1,2,4-triazine 5 (Scheme 3). We have
recently reported on the structural elucidation of 3 and
found that C=O length is 123.6(3) pm and C=S length is
165.4(3) pm [6]. These data clearly show that C=O
bond is stronger than C=S bond and should be cleaved
Scheme 1
more easily. The only explanation for this reverse attack
could be the existence of preferred tautomeric form of
triazinone 6 over triazine thione 7.
Result and Discussion.
6-Methyl-4-amino-1,2,4-triazine-3-thione-5-one 3 was
reacted with benzonitrile in the presence of potassium t-
butoxide in t-butyl alcohol at reflux temperature [5]. After
cooling the mixture and acidification of the solution, a crys-
talline compound was obtained in 79% yield. The absence
In addition, we used semiempirical (AM1) and ab initio
calculation to estimate that triazinone 8 (-1524.98 au) is more
stable than triazine thione 9 (-1508.08 au) and should exist
predominantly. In addition, the IR spectrum of compound 3
1
of a band for amide carbonyl group in IR, H NMR data,
the exact mass measurement and microanalysis suggested
-1
shows a vibration band for carbonyl group at 1707 cm .

1022
M. M. Heravi, N. Montazeri, M. Rahimizadeh, M. Bakavoli and M. Ghassemzadeh
Vol. 42
Scheme 2
pound 4 (Ar = Ph) was methylated to give the methylthio
derivative 10 (Scheme 4), then the methylthio group was
replaced by amines (morpholine) to afford 11a-b.
In conclusion, we have developed a facile and high yield-
ing method for the synthesis of various 1,2,4-triazolo[1,5-d]-
1,2,4-triazin-5-thiones from readily available starting materi-
als. This method is carried out in a relatively mild condition
and does not involve any toxic reagent. The only drawback
of this method is that we could not use aliphatic nitriles.
Scheme 3
To establish the generality of the method, various aryl
nitriles were efficiently reacted with 3 to obtain 4 in good
to high yields (Table 1).
EXPERIMENTAL
The melting points are uncorrected and were obtained by a
Kofler Heizbank Reichart type 7841 melting point apparatus. IR
spectra were obtained on a 4300 Shimadzu spectrometer. The H
NMR spectra were recorded on a Bruker AC 100, unless otherwise
stated using TMS as standard reference. Mass spectra scanned on a
Varian CH-7 instrument at 70 eV. Microanalyses were performed
in Iranian Oil Research Center of Iran, Tehran, Iran.
It is noteworthy to mention that p-aminobenzonitrile and
p-hydroxybenzonitrile did not react with 3 under the above
reaction conditions. However, after protection of amino
and hydroxy groups by acetylation, reaction occurred.
Deprotection gave the corresponding 1,2,4-triazolo[1,5-d]-
1,2,4-triazines (enteries 4i and 4j). Unreactivity of p-
aminobenzonitrile and p-hydroxylbenzonitrile may be due
to strong electron releasing of amino and hydroxyl group
making the nitrile group less electrophilic. Although the
present method tolerates substantial variation in aryl nitrile
as the substrate (Table 1), alkyl nitriles did not react. We
have no explanation for this lack of reactivity and perhaps
elucidation of the precise answer to this question needs
further investigations.
1
Synthesis of 1,2,4-Triazolo[1,5-d]-1,2,4-triazin-5-thiones.
General Procedure.
t
Potassium (0.195 g, 5 mmol) was dissolved in BuOH (30
mL). To this solution compound 3 (0.515 g, 5 mmol) and an
appropriate nitrile (5 mmol) were added. This mixture was
refluxed for 4 hrs. After cooling, the mixture was filtered and to
the filtrate 10% HCl was added dropwise. The resulting solid
was collected by filtration and crystallized from a suitable sol-
vent. The products were characterized by spectroscopic and
analytical data.
To prove our structure and open a way to synthesiz vari-
ous derivatives of 1,2,4-triazolo[1,5-d]-1,2,4-triazine, com-

Jul-Aug 2005
Communication to the Editor
1023
Table
Synthesis of 1,2,4-Triazolo[1,5-d]-1,2,4-triazine-5-thiones
Table (continued)
Product
Entry Arylnitrile
Yield (%)
62
4i
Entry Arylnitrile
Product
Yield (%)
4j
68
73
4a
79
4k
4b
80
4l
75
88
4c
4d
4e
4f
82
80
76
85
4m
[a] Yields refer to isolated products.
2-Phenyl-8-methyl-6H-1,2,4-triazolo[1,5-d]1,2,4-triazine-5-one
(4a).
This compound was obtained in 79% yield, mp: 282-3 °C
1
(EtOH); H NMR, (d -DMSO): δ 2.61 (s, 3H, CH ), 7.59 (m,
6
3
3H, ArH), 8.23 (m, 2H, ArH), 14.6 (s, broad, 1H, NH); IR
(KBr disc) 3250, 1600, 1520, 1480, 1440 cm ; MS m/z M
-1
+
243(5), 242(26), 241(70), 240(100), 212(31), 211(46),
185(51), 179(77), 157(31), 143(25).
Anal. Calcd. for C H N S: C, 54.32; H, 3.70; N, 28.80; S,
11
9 5
13.16. Found C, 55.00; H, 3.60; N, 28.60; S, 12.3.
2-(p-Bromophenyl)-8-methyl-6H-1,2,4-triazolo[1,5-d]1,2,4-tri-
azine-5-one (4b).
4g
4h
84
60
This compound was obtained in 80% yield, mp: 250-2 °C
1
(benzene); H NMR, (d -DMSO): δ 2.59 (s, 3H, CH ), 7.79 (d, J
6
3
= 7.8 Hz, 3H, ArH), 8.16 (d, J = 7.8 Hz, 2H, ArH), 14.6 (s, broad,
-
1H, NH); IR (KBr disc) 3120, 3080, 2980, 1595, 1515, 1440 cm
1
+
+
; MS m/z M +2: 324(29), M+1: 323(60), M : 322(28), 265(10),
185(82), 184(92), 182(100), 181(86), 114(40), 102(88);
Anal. Calcd. for C H BrN S: C, 40.99; H, 2.48; N, 21.73.
11
8
5
Found: C, 41.03; H, 2.35; N, 21.61.

1024
M. M. Heravi, N. Montazeri, M. Rahimizadeh, M. Bakavoli and M. Ghassemzadeh
Vol. 42
-1
+
2-(p-Chlorophenyl)-8-methyl-6H-1,2,4-triazolo[1,5-d]1,2,4-tri-
azine-5-one (4c).
disc) 3300, 31501670, 1600, 1525, 1455, 1320 cm ; MS m/z M
300(6), 299(67), 298(67), 297(100), 254(25), 253(65), 198(44),
183(26), 182(82), 156(38), 130(20).
This compound was obtained in 82% yield, mp: 216-7 °C
Anal. Calcd. for C
H N OS: C, 52.00; H, 4.00; N, 28.00.
1
14 13 5
(benzene/EtOH, 50/50); H NMR, (d -DMSO): δ 2.6 (s, 3H,
6
Found: C, 52.30; H, 4.07; N, 27.86.
CH ), 7.64 (d, J = 8.4 Hz, 3H, ArH), 8.21 (d, J = 8.4 Hz, 2H,
3
ArH), 14.61 (s, broad, 1H, NH); IR (KBr disc) 3150, 3080, 1995,
1520, 1445 cm ; MS m/z M 277(5), 276(13), 275(73),
273(100), 244(21), 215(34), 139(36), 136(73), 114(56).
2-(p-Aminophenyl)-8-methyl-6H-1,2,4-triazolo[1,5-d]1,2,4-tri-
azine-5-one (4i).
-1
+
This compound was obtained in 62% yield, mp: 323-4 °C (ace-
Anal. Calcd. for C H ClN S: C, 47.57; H, 2.90; N, 25.21.
11
8
5
1
tone); H NMR, (d -DMSO): δ 2.45 (s, 3H, CH ), 5.55 (s, broad,
6
3
Found: C, 47.43; H, 2.86; N, 25.81.
2H, NH ), 6.65 (d, J = 7.85 Hz, 2H, Ar-H), 7.72 (d, J = 7.85 Hz,
2
2-(p-Flourophenyl)-8-methyl-6H-1,2,4-triazolo[1,5-d]1,2,4-tri-
azine-5-one (4d).
2H, Ar-H), 14.21 (s, broad, 1H, NH); IR (KBr disc) 3420, 3350,
-1
+
2985, 1615, 1495, 1440, 1300 cm ; MS m/z M 258(2), 257(4),
255(57), 237(15), 214(26), 210(100), 183(35), 158(34), 118(36),
116(92).
This compound was obtained in 80% yield, mp: 264-5 °C
1
(EtOH); H NMR, (d -DMSO): δ2.6 (s, 3H, CH ), 7.41 (t, J = 8.8
6
3
Anal. Calcd. for C
H N S: C, 56.01; H, 4.30; N, 27.21.
12 11 5
Hz, 2H, ArH), 8.25 (q, J = 7.6 Hz, 2H, ArH), 14.25 (s, broad, 1H,
Found: C, 56.28; H, 4.09; N, 26.91
..
-1
NH); IR (KBr disc) 3230, 3070, 1610, 1515, 1495 cm ; MS m/z
+
M
261(6), 260(23), 259(60), 258(100), 195(22), 193(24),
2-(p-Hydroxyphenyl)-8-methyl-6H-1,2,4-triazolo[1,5-d]1,2,4-
triazine-5-one (4j).
157(16), 156(15), 155(14).
Anal. Calcd. for C H FN S: C, 50.56; H, 3.08; N, 26.80.
11
8
5
This compound was obtained in 68% yield, mp: 331-2 °C
Found: C, 50.45; H, 2.99; N, 27.00.
1
(EtOH); H NMR, (d -DMSO): δ 2.58 (s, 3H, CH ), 6.94 (d, J =
6
3
2-(p-Methoxyphenyl)-8-methyl-6H-1,2,4-triazolo[1,5-d]1,2,4-
triazine-5-one (4e).
8.27 Hz, 2H, Ar-H), 8.05 (d, J = 8.27 Hz, 2H, Ar-H), 10.13 (s,
broad, 1H, OH), 14.6 (s, broad, 1H, NH); IR (KBr disc) 3400,
-1
+
3150, 1605, 1500, 1435, 1320 cm ; MS m/z M 259(4), 258(33),
257(84), 256(100), 225(31), 224(39), 196(4), 195(75), 166(24),
153(21), 135(31), 103(51).
This compound was obtained in 76% yield, mp: 223-4 °C
1
(EtOH); H NMR, (d -DMSO): δ 2.59 (s, 3H, CH ), 3.8 (s, 3H,
6
3
OCH ), 7.12 (d, J = 8.82 Hz, 2H, ArH), 8.11 (d, J = 8.82 Hz, 2H,
3
Anal. Calcd. for C
H N OS: C, 50.96; H, 3.47; N, 27.02.
12 10 4
ArH), 14.55 (s, broad, 1H, NH); IR (KBr disc) 2980, 2910, 1585,
Found: C, 49.88; H, 3.90; N, 26.03.
-1
+
1530, 1490, 1440 cm ; MS m/z M 273(4), 271(20), 269(6),
267(100), 223(19), 109(87), 133(70), 132(73), 119(31).
2-(9-Phenanthrenyl)-8-methyl-6H-1,2,4-triazolo[1,5-d]1,2,4-tri-
azine-5-one (4k).
Anal. Calcd. for C H N OS: C, 52.73; H, 4.05; N, 25.62.
12 11
5
Found: C, 52.68; H, 4.00; N, 25.70.
This compound was obtained in 73% yield, mp: 302-3 °C
2-(2,3-Dimethoxyphenyl)-8-methyl-6H-1,2,4-triazolo[1,5-d]-
1,2,4-triazine-5-one (4f).
1
(EtOH/ DMAc); H NMR, (d -DMSO): δ 2.66 (s, 3H, CH ), 7.72
6
3
– 9.18 (m, 9H, Ar-H), 14.68 (s, broad, 1H, NH); IR (KBr disc)
-1
+
3420, 3350, 2985, 1615, 1495, 1440, 1300 cm ; MS m/z M
This compound was obtained in 85% yield, mp: 355-6 °C
1
343(4), 342(14), 341(48), 340(100), 280(15), 279(60), 265(38),
199(69), 186(15), 174(12).
(benzene); H NMR, (d -DMSO): δ 2.60 (s, 3H, CH ), 3.85 (s,
6
3
6H, 2 CH -O), 6.7 (d, J = 2.14 Hz, 1H, Ar-H), 7.32 (d, J = 2.14
3
Anal. Calcd. for C
H N S: C, 66.47; H, 3.82; N, 20.40.
Hz, 2H, Ar-H), 14.58 (s, broad, 1H, NH); IR (KBr disc) 3250,
19 13 5
-1
+
Found: C, 66.75; H, 3.82; N, 20.34.
3020, 1600, 1520, 1460, 1415, 1330 cm ; MS m/z M 303(30),
231(6), 230(11), 165(100), 163(35), 134(5).
2-(2-Thiophenyl)-8-methyl-6H-1,2,4-triazolo[1,5-d]1,2,4-tri-
azine-5-one (4l).
Anal. Calcd. for C
H N O S: C, 51.48; H, 4.29; N, 23.10.
13 13 5 2
Found: C, 51.32; H, 4.27; N, 22.98.
This compound was obtained in 75% yield, mp: 277-8 °C
2-(m-Methylphenyl)-8-methyl-6H-1,2,4-triazolo[1,5-d]1,2,4-tri-
azine-5-one (4g).
1
(EtOH); H NMR, (d -DMSO): δ 2.59 (s, 3H, CH ), 7.27 (dd, J =
6
3
4.9 Hz, 1H, Ar-H), 7.9 (dd, J = 4.3 Hz, 2H, Ar-H), 14.6 (s, broad,
This compound was obtained in 84% yield, mp: 234-5 °C
1H, NH); IR (KBr disc) 3240, 3080, 1595, 1560, 1470, 1410
1
-1
+
(EtOH); HNMR, (d -DMSO): δ 2.48 (s, 3H, CH ), 2.6 (s, 3H,
cm ; MS m/z M 249(3), 246(4), 247(12), 245(100), 216(11),
214(30), 186(95), 170(42), 157(16), 148(22), 124(49), 119(48),
108(91).
6
3
CH ), 7.48 (m, 2H, Ar-H), 8.0 (m, 2H, Ar-H), 14.6 (s, broad, 1H,
3
-1
NH); IR (KBr disc) 3140, 3070, 1595, 1515, 1450, 1355 cm ;
MS m/z M 257(6), 256(34), 255(52), 254(88), 224(38), 223(46),
+
Anal. Calcd. for C H N S : C, 66.47; H, 3.79; N, 20.40.
9
7 5 2
194(55), 132(20), 115(80).
Found: C, 66.75; H, 3.82; N, 20.34.
Anal. Calcd. for C
Found: C, 55.97; H, 4.25; N, 26.98.
H N S: C, 56.01; H, 4.30; N, 27.21.
12 11 5
2-(4-Pyridinyl)-8-methyl-6H-1,2,4-triazolo[1,5-d]1,2,4-triazine-
5-one (4m).
2-(p-Acetanilide)-8-methyl-6H-1,2,4-triazolo[1,5-d]1,2,4-tri-
azine-5-one (4h).
This compound was obtained in 88% yield, mp: 363-4 °C
1
(EtOH/ DMAc); H NMR, (d -DMSO): δ 2.62 (s, 3H, CH ), 7.1
6
3
This compound was obtained in 60% yield, mp: 301-3 °C
(d, J = 4.86 Hz, 2H, Ar-H), 8.8 (d, J = 4.86 Hz, 2H, Ar-H), 14.62
1
(EtOH); H NMR, (d -DMSO): δ 2.09 (s, 3H, CH ), 2.6 (s, 3H,
(s, broad, 1H, NH); IR (KBr disc) 3250, 3070, 1600, 1510, 1450,
6
3
-1
+
CH ), 7.75 (d, J = 8.54 Hz, 2H, Ar-H), 8.2 (d, J = 8.54 Hz, 2H,
1385 cm ; MS m/z M 244(5), 243(7), 242(100), 241(22),
181(25), 104(33), 120(27), 82(23), 54(5), 51(3), 50(7).
3
Ar-H), 10.22 (s, 1H, NH), 14.58 (s, broad, 1H, NH); IR (KBr

Jul-Aug 2005
Communication to the Editor
1025
Anal. Calcd. for C H N S: C, 49.18; H, 3.27; N, 34.42.
Found: C, 48.98; H, 3.43; N, 34.01.
Compound 10 (0.257 g, 0.001 mol) and benzylamine (0.214 g,
0.002 mol) in ethanol (5 mL) were refluxed for 8 hrs. The reac-
tion mixture was cooled down to room temperature and the pre-
cipitated solid was collected by filtration, washed with water and
crystallized from EtOH to afford the titled compound. This com-
10
8 6
8-Methyl-5-methylthio-2-phenyl-6H-1,2,4-triazolo[1,5-d]-1,2,4-
triazine (10).
Compound 4a (1.215 g, 0.005 mol) was dissolved in 0.5 N
sodium hydroxide solution (15 mL). To this solution methyl
iodide (0.44 mL, 0.005 mol) was added dropwise at room tem-
perature. This mixture was stirred for 4 hrs at ambient tempera-
ture. The precipitated solid was collected by filtration, washed
with water and crystallized from EtOH to afford the titled com-
1
pound was obtained in 73% yield, mp: 166-8 °C (EtOH);
H
NMR, (CDCl ): δ 2.87 (s, 3H, CH ), 4.96 (d, 2H, CH ), 6.14 (t,
3
3
2
1H, NH), 7.46 (m, 8H, 2 Ar-H), 8.26 (m, 2H, 2 Ar-H); IR (KBr
-1
+
disc) 3200, 3040, 2920, 1610, 1465 cm ; MS m/z M 316(5),
315(27), 314(68), 284(51), 141(82), 140(64), 129(63), 113(53),
102(79), 90(100), 88(37).
pound. This compound was obtained in 67% yield, mp: 157-8 °C
Anal. Calcd. for C
H N : C, 68.33; H, 5.97; N, 26.56.
18 16 6
1
(EtOH); H NMR, (CDCl ): δ 2.86 (s, 3H, CH ), 2.96 (s, 3H, -
3
3
Found: C, 67.99; H, 5.89; N, 26.61.
SCH ), 7.5 (m, 3H, Ar-H), 8.32 (m, 2H, Ar-H); IR (KBr disc)
3
-1
+
3050, 1520, 1440, 1395, 1320 cm , MS m/z M 257(4), 256(32),
254(100), 185(37), 169(44), 143(42), 108(82), 107(28), 81(19),
71(12).
REFERENCES AND NOTES
Anal. Calcd. for C
Found: C, 56.28; H, 4.09; N, 26.91.
H N S C, 56.03; H 4.28; N, 27.23.
12 11 5
[1a] D. T. Hurst, Prog. Heterocyclic Chem., 7, 244 (1995); [b]
H. Groger, J. Sans and T. Gunther, Chim. Oggi, 18, 12 (2000).
[2] F. M. Adam, A. J. Burton, K. S. Cardwell, R. A. Cox, R.
A. Henson, K. Mills, J. C. Prodger, M. B. Shilling and D. T. Tape,
Tetrahedron Lett., 44, 5657 (2003).
8-Methyl-5-morpholino-2H-phenyl-6H-1,2,4-triazolo[1,5-d]-
1,2,4-triazine (11a).
Compound 10 (0.257 g, 0.001 mol) and morpholine (0.174 g,
0.002 mol) in ethanol (5 mL) were refluxed for 8 hrs. The mix-
ture was cooled to room temperature and the precipitated solid
was collected by filtration, washed with water and crystallized
[3a] M. M. Heravi and M. Bakavoli, J. Chem. Res., 11, 480
(1995); [b] M. M. Heravi, K. Aghapoor and M. A. Nooshabadi,
Synth. Commun., 28, 233 (1998); [c] M. M. Heravi, K. Aghapoor, M.
A. Nooshabadi and M. M. Mojtahedi, Monatsh. Chem., 128, 1143
(1997); [d] M. M. Heravi, A. Kivanloo, M. Rahimizadeh, M.
Bakavoli and M. Ghassemzadeh, Phosphorus, Sulfur and Silicon,
177, 249 (2002); [e] M. M. Heravi, A. Kivanloo, M. Rahimzadeh, M.
Bakavoli and M. Ghassemzadeh, Tetrahedron Lett., 45, 5747 (2004);
[f] M. M. Heravi, A. Kivanloo, M. Rahimzadeh, M. Bakavoli, M.
Ghassemzadeh and B. Neumüller, Tetrahedron Lett., 46, 1607
(2005).
[4 C. A. Lovelette and K. Geagon, J. Heterocyclic Chem., 19,
1345 (1982).
[5] A. Dornow, H. Menzel and P. Marx, Ber., 2179 (1964).
[6] M. Ghassemzadeh, K. Aghapoor, M. M. Heravi and B.
Neumüller, Z. Anorg. Allg. Chem., 624, 1969 (1998).
from EtOH to afford the titled compound. This compound was
1
obtained in 81% yield, mp: 196-7 °C (EtOH); H NMR, (d -
6
DMSO): δ 2.75 (s, 3H, CH ), 3.91 (d, J = 3.8 Hz, 8H, morpho-
3
line-H), 7.58 (m, 3H, Ar-H), 8.23 (m, 2H, Ar-H); IR (KBr disc)
-1
+
2980, 2910, 1585, 1530, 1490, 1440 cm ; MS m/z M 273(4),
271(20), 269(6), 267(100), 223(19), 209(87), 133(70), 132(73),
119(31).
Anal. Calcd. for C
H N O: C, 40.99; H, 2.48; N, 21.73.
15 16 6
Found: C, 41.03; H, 2.35; N, 21.61.
8-Methyl-5-benzylamino-2-phenyl-6H-1,2,4-triazolo[1,5-d]-
1,2,4-triazine (11b).