Novel N-(S-amino)sulfenylated derivatives of diacylhydrazines
2
benzoylhydrazine (1b,X=3,5-CH ) )
.2.2 N-tert-Butyl-N’-benzoyl-N-3,5-dimethyl-
CH CH ); 1.66 (s, 9H, C(CH ) ); 2.40–3.42 (m, 4H,
CH N); 6.89–7.62 (m, 10H, Ph). calc for
2
2
3 3
3
Compound lb was prepared in a similar way to la:
2
2
C H N O S:C, 68.53; H, 8.18; N, 9.22; found: C,
26
37
3
2
68.27; H, 8.20; N, 9.17.
1
yield, 86.3%; mp 202–204°C; H NMR (CDCl3)
d (ppm): 1.56 (s, 9H, C(CH ) ); 2.20 (s, 6H,
Ph—CH ); 6.86–7.40 (m, 8H, Ph); 7.92 (s, 1H,
3
3
2.3 Biological assay
3
NH); calc for C H N O :C, 74.05; H, 7.46; N,
The larvicidal activities of the N-(S-amino)sulfeny-
lated derivatives 3a, 3b, 3c and the parent compounds,
la, lb, were evaluated using a previously reported
2
0
24
2
2
.36; found: C, 74.23; H, 7.19; N, 8.07.
8
8
,9
2
.2.3 Morpholinosulfenyl chloride (2a)
procedure. The larvicidal activity was tested against
Oriental armyworm [Mythimna (=Pseudaletia) separ-
ata (Walker)] by foliar application. For the foliar
armyworm tests, individual corn leaves were placed on
moistened pieces of filter paper in Petri dishes. The
leaves were then sprayed with the test solution and
allowed to dry. The dishes were infested with ten 4th-
instar armyworm larvae. Percentage mortalities were
evaluated 4 days after treatment. Evaluations are
based on a percentage scale of 0–100 in which 0=no
activity and 100=total kill. For comparative purposes,
the parent compound (1) was tested under the same
conditions. The larvicidal activity is summarized in
Table 1.
A solution of morpholine (0.35g, 4.05mmol) and
pyridine (0.35g, 4.46mmol) in methylene dichloride
(
(
5ml) was added dropwise with stirring to a cold
ꢀ10°C) solution of sulfur dichloride (0.50g,
4
.86mmol) in methylene dichloride (8ml). The rate
of addition was controlled to maintain the temperature
in the range of ꢀ5°C to 10°C. The reaction mixture
was stirred at ꢀ5°C to 10°C for 0.5h, then at room
temperature for 24h. The reaction mixture was
filtered, and the filtrate was concentrated under
reduced pressure to give a yellow liquid. The residue
was used for further operations without purification.
2.2.4 N-tert-Butyl-N’-morpholinosulfenyl-N,N’-
dibenzoylhydrazine (3a) and similar compounds
To a stirred solution of N-tert-butyl-N’-benzoyl-N-
benzoylhydrazine (la) (1.20g, 4.05mmol) in anhy-
drous tetrahydrofuran (40ml), was added portionwise
sodium hydride (0.114g, 85% purity, 4.05mmol) at
room temperature under nitrogen. The mixture was
stirred at room temperature for 0.5h and cooled to
3 RESULTS AND DISCUSSION
N-(S-Amino)sulfenylated derivatives of diacylhydra-
zines (3a, 3b, 3c) were prepared by the reaction of the
appropriate aminosulfenyl chlorides (2) with N-tert-
butyl-N’-benzoyl-N-substituted
benzoylhydrazines
(1) in the presence of sodium hydride, as shown in
Fig 1. The aminosulfenyl chlorides (2) were prepared
in excellent yields by the reaction of sulfur dichloride
with secondary amines in dichloromethane using
pyridine as the acid acceptor. N-tert-Butyl-N-substi-
tuted benzoylhydrazines were synthesized in a new
0
4
°C. Then morpholinosulfenyl chloride (2a; 0.63g,
.05mmol) was added dropwise. After the addition
was complete, the reaction mixture was stirred for 5h
at room temperature. The solid was then filtered off
and the filtrate concentrated under vacuum. The
residue was purified by column chromatography on
silica gel using petroleum ether (60–90°C)þethyl
acetate (5þ1 by volume) as the eluent. Finally,
colourless crystals of 3a were obtained: yield, 66.1%;
1
0–13
procedure with a good yield as shown in Fig 1,
and subsequent acylation with benzoyl chloride
yielded N-tert-butyl-N’-benzoyl-N-substituted-ben-
zoylhydrazines (1) in excellent yields.
ꢀ1
mp 162–163°C; IR (KBr, cm ) 3050, 2904, 1663,
632, 1388, 1356, 1125, 1076, 962, 793, 741, 718;
The aminosulfenyl chlorides (2) without further
purification were reacted with N-tert-butyl-N,N’-
dibenzoylhydrazines (1) to give products (3). A small
amount of N-tert-butyl-benzamide (4) and benzamide
(5) were isolated as by-products. We found that
treatment of N-tert-butyl-N,N’-dibenzoylhydrazine
with sulfur dichloride in the presence of sodium
1
1
H NMR (CDCl ) d (ppm): 1.66 (s, 9H, C(CH ) );
3
3 3
2
.36–3.69 (m, 8H, O(CH CH ) N); 6.90–7.54 (m,
2 2 2
1
0H, Ph); calc for C H N 0 S:C, 63.90; H, 6.58;
2
2
27
3 3
N, 10.16; found: C, 63.77; H, 6.59; N, 10.23.
N-tert-Butyl-N’-morpholinosulfenyl-N-3,5-di-
methylbenzoyl-N’-benzoylhydrazine (3b) and N-tert-
butyl-N’-(N,N-dibutylamino)sulfenyl-N,N’-diben-
zoylhydrazine (3c) were prepared in a similar way to
Table 1. Larvicidal activities of N-(S-amino)sul-
fenylated-N-tert-butyl-N,N’-dibenzoylhydrazines
(
3) and parent compounds (1)
3
a by using the corresponding S-aminosulfenyl chlor-
ides.
b. Yield, 70.3%; mp 148–150°C; H NMR
CDCl ) d (ppm): 1.70 (s, 9H, C(CH ) ); 2.34
Larvicidal activity (%) at
ꢀ
1
1
)
3
concentration (mg kg
(
(
3
3 3
Compound 500 200 100
50
s,6H,
Ph—CH );
2.60–3.80
(m,
8H,
3
3
3
3
1a
1
a
b
c
100
95
50
85
5
O(CH CH ) N); 6.92–7.60 (m, 8H, Ph); calc for
C H N O S:C, 65.28; H, 7.08; N, 9.52; found: C,
2
2 2
100 100
60
0
2
4
31
3
3
5.40; H, 7.05; N, 9.62.
100 100 100
100 100 100
6
1
95
3
c. Yield, 56.8%; mp 61–62°C; H NMR (CDCl )
3
b
100 100 100 100
d (ppm): 0.73 (t, 6H, C-CH ); 0.94–1.42 (m, 8H,
3
Pest Manag Sci 58:1250–1253 (online: 2002)
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