Anti-inflammatory activity of heterocyclic systems using abietic acid as starting material

Article abstract of DOI:10.1007/s00706-007-0804-1

A series of pyridines, pyrimidinone, oxazinones, and their derivatives were synthesized as anti-inflammatory agents using abietic acid (7-isopropyl-1,4a- dimethyl-1,2,3,4,4a,4b,5,6,10,10a-decahydrophenanthrene-1-carboxylic acid) as the starting material. The arylidiene derivative was treated with cyanothioacetamide to give cyano pyridine-thione, which was reacted with ethyl chloroacetate to yield the corresponding cyano ester. The ester was hydrolysed to the sodium salt, which was reacted with acetic anhydride to afford 2-methyloxazinone, which was treated with ammonium acetate to afford 2-methylpyrimidinone followed by methylation with methyl iodide to yield 2,3-dimethyl- pyrimidinone. In addition, the oxazinone derivative was reacted with aniline or hydrazine hydrate to give 3-phenyl- or 3-aminopyrimidinones. The latter reacted with thiophene-2-carboxaldehyde or phenylisothiocyanate to afford Schiff's bases or thiosemicarbazide derivatives. The pharmacological screening showed that many of these compounds have good anti-inflammatory activity comparable to Prednisolone as reference drug.

Full text of DOI:10.1007/s00706-007-0804-1

Monatsh Chem 139, 697–705 (2008)
DOI 10.1007/s00706-007-0804-1
Printed in The Netherlands
Anti-inflammatory activity of heterocyclic systems using abietic acid
as starting material
Mohamed M. Abdulla
Research Units, Hi-Care Pharmaceutical Co., Cairo, Egypt
Received 20 August 2007; Accepted 12 September 2007; Published online 19 May 2008
# Springer-Verlag 2008
Abstract A series of pyridines, pyrimidinone, oxaz-
inones, and their derivatives were synthesized as
anti-inflammatory agents using abietic acid (7-iso-
propyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a-dec-
ahydrophenanthrene-1-carboxylic acid) as the
starting material. The arylidiene derivative was
treated with cyanothioacetamide to give cyano pyr-
idine-thione, which was reacted with ethyl chloro-
acetate to yield the corresponding cyano ester. The
ester was hydrolysed to the sodium salt, which was
reacted with acetic anhydride to afford 2-methylox-
azinone, which was treated with ammonium acetate
to afford 2-methylpyrimidinone followed by meth-
ylation with methyl iodide to yield 2,3-dimethyl-
pyrimidinone. In addition, the oxazinone derivative
was reacted with aniline or hydrazine hydrate to
give 3-phenyl- or 3-aminopyrimidinones. The latter
reacted with thiophene-2-carboxaldehyde or phenyl-
isothiocyanate to afford Schiff’s bases or thio-
semicarbazide derivatives. The pharmacological
screening showed that many of these compounds
have good anti-inflammatory activity comparable
to Prednisolone+ as reference drug.
Introduction
In our previous work we have found that certain
substituted pyridines and their derivatives show an-
timicrobial and pharmacological properties [1–5]
and antitumor activities [6, 7]. In addition, the bio-
logical and analgesic activities of many heterocyclic
compounds containing a sulfur atom have been
reviewed [8–11]. On the other hand, thienopyrimi-
dine and thioxopyrimidine derivatives have promis-
ing biological [12, 13] and anticancer activities [14,
15]. Recently, some new pyridines, pyrimidines, and
their derivatives have been synthesized and used as
analgesic, anticonvulsant and antiparkinsonian agents
[16–22]. In view of these observations and in contin-
uation of our previous work in pyridine chemistry, we
synthesized some new heterocyclic compounds con-
taining the thiophene ring fused with a pyridine, oxa-
zinone, or pyrimidinone nucleus and tested their
anti-inflammatory activity.
Results and discussion
Keywords Abietic acid; Oxazinone; Pyrimidinone; Anti-in-
flammatory; Prednisolone+.
Synthesis
The starting materials 3 and 4 were prepared from
abietic acid (7-isopropyl-1,4a-dimethyl-1,2,3,4,4a,
4b,5,6,10,10a-decahydrophenanthrene-1-carboxylic
acid, 1) via the corresponding acid 1-(7-isopro-
pyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a-decahy-
drophenanthrene-1-yl)ethanone (2) according to
Correspondence: Mohamed M. Abdulla, Research Units, Hi-
Care Pharmaceutical Co., Cairo, Egypt. E-mail: mohamed_
mostafa211@hotmail.com

698
M. M. Abdulla
literature methods [1, 23]. Thionation of 4 to the
corresponding thione derivative 5 was achieved by
the action of P2S5 in dry pyridine (method A), which
was prepared directly from 3 with cyanothioacet-
amide in the presence of ammonium acetate in re-
fluxing ethanol (method B). Condensation of 5 with
ethyl chloroacetate in the presence of anhydrous
K2CO3 gave the ethyl ester derivative 6, which
was cyclized by sodium methoxide in methanol to
give the amino ester derivative 7 (Scheme 1). The IR
Scheme 1

Heterocyclic systems using abietic acid
699
spectra of 7 showed the absence of ꢀꢀ (CꢀN) for 6 and
the presence of a broad band corresponding to ꢀꢀ(NH2).
Compound 7 was hydrolyzed by refluxing with
ethanolic NaOH solution to the corresponding
sodium salt (A), which was treated with refluxing
acetic anhydride to give the oxazinone derivative 8.
Reaction of 8 with ammonium acetate in refluxing
acetic acid afforded the corresponding pyrimidinone
derivative 9, which was treated with methyl iodide in
N,N-dimethylformamide in the presence of anhy-
drous K2CO3 to yield the 3-methyl-pyrimidinone de-
rivative 10 (Scheme 2).
Similarly, reaction of oxazinone 8 with aniline
in acetic acid or with hydrazine hydrate in
ethanol under reflux afforded the 3-phenyl- and
3-aminopyrimidines 11 and 12. Condensation of
12 with thiophene-2-carboxaldehyde in reflux-
ing ethanol containing a few drops of pipridine
yielded the corresponding Schiff’s base 13. Also,
12 was treated with phenylisothiocyanate in re-
Scheme 2

700
M. M. Abdulla
Scheme 3
fluxing dioxane to give the thiosemicarbazide 14
(Scheme 3).
Purpose and rational
For the determination of the antiphlogistic potency
of the synthesized compounds, two standard tests
were realized at 25 and 50 mg=kg body weight of
the rats, namely the protection against carrageen-
an-induced edema according to Winter et al. [24]
and the inhibition of plasma PGE2. The latter is
known as a good confirming indicator for the car-
ragenan-induced rat paw edema [25]. Regarding
the protection against carrageenan-induced edema,
all the tested compounds showed potent anti-in-
flammatory activities. The order of activity in de-
scending manner is 9, 10, 11, 12, 13, 14, 8, 7, 6, 5,
4, 3, and 2.
Pharmacological screening
Anti-inflammatory potency
Initially the acute toxicity of the compounds was
assayed determining their LD50. Interestingly, all the
synthesized compounds and starting materials were
less toxic than the reference drug (Table 1). Then
the newly synthesized compounds were pharmaco-
logically screened for their anti-inflammatory potency
using male albino rats (Tables 2 and 3).

Heterocyclic systems using abietic acid
701
Table 1 Acute toxicity LD50 of the synthesized and starting
compounds
Table 3 Anti-inflammatory potency of the synthesized com-
pounds (inhibition of plasma PGE2)
Compound no.
LD50=mg kgꢁ1
Compound no.
Dose=
mg kgꢁ1
Inhibition of
plasma PGE2=%
Prednisolone+
1
2
3
4
5
6
7
8
1.618
2.758
2.987
2.984
2.121
2.764
3.984
3.6745
3.694
3.987
3.987
3.932
2.987
2.342
3.256
Prednislone+
25
50
25
50
25
50
25
50
25
50
25
50
25
50
25
50
25
50
25
50
25
50
25
50
25
50
25
50
25
50
77.00c
91.00c
67.00a
79.13b
68.78a
80.65b
69.50c
81.66c
70.55b
82.98a
71.16c
83.19c
72.19a
84.56b
73.12b
84.25a
75.12c
85.18c
83.78a
91.18b
82.16c
90.14c
80.14b
90.00b
79.24a
88.19a
77.14c
87.14c
76.12c
86.12a
1
2
3
9
4
10
11
12
13
14
5
6
7
Table 2 Anti-inflammatory potency of the synthesized com-
pounds (protection against Carragenan+ induced edema)
8
9
Compound no.
Dose=
mg kgꢁ1
Protection against
carrageenan+ induced
edema=%
10
11
12
13
14
Prednisilone+
25
50
25
50
25
50
25
50
25
50
25
50
25
50
25
50
25
50
25
50
25
50
25
50
25
50
25
50
25
50
81.00a
93.00b
80.00c
93.00a
80.80c
84.85c
81.18b
87.45c
83.19a
88.45b
85.88c
90.19c
87.56c
91.19a
88.12c
93.18b
90.90c
94.12b
96.43c
99.68c
95.12b
98.13b
94.13c
98.00a
93.00a
97.44b
92.16b
96.17b
91.25b
95.19b
1
2
3
4
a
b
P<0.05; P<0.01; P<0.001
c
5
Structural activity relationship (SAR)
6
1. As the degree of poly heterocyclic fused system
increases the anti-inflammatory activity increases.
2. The triazafluorene system is more active than
thae diaza one.
3. Free NH on the pyrmidine nucleus is more active
than substituted ones (the order of activity of
N-sustituents is methyl, phenyl, amino, thienyl-
methene, and thiourea).
4. S-substitution increases the anti-inflammatory
activities.
5. The thion derivative increase anti-inflammatory
than carbonyl function.
7
8
9
10
11
12
13
14
Experimental
All melting points were taken on Electrothermal IA 9000
series digital melting point apparatus. Elemental analytical
a
b
P<0.05; P<0.01; P<0.001
c

702
M. M. Abdulla
data (in accord with the calculated values) were obtained from
the microanalytical unit, Cairo University, Cairo, Egypt.
Optical relations were measured with an Atago Polax-D
polarimeter. The IR spectra (KBr) were recorded on a Pye
Unicam SP-1000 spectrophotometer. The 1H NMR spectra
were recorded at 270 MHz on Varian EM-360 Spectrometer
using TMS as an internal standard at the Central Services
Laboratory, Cairo University, Egypt. The mass spectra were
performed using VG 2AB-3F spectrometer (70 eV). All reac-
tions were followed by TLC (silica gel, aluminum sheets
60 F254, Merck). Starting materials 2–4 were prepared from
abietic acid 1 according to published procedures [1, 23].
130, 136, 137, 145.3 (olefin), 152.3 (olefin), 162.9 (CO),
170.0 ppm; MS (EI, 70eV): m=z ¼ 458 [Mþ, 100, base peak].
6-(7-Isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a-deca-
hydrophenanthrene-1-yl)-4-thien-2-yl-2-thioxo-1,2-dihydro-
pyridine-3-carbonitrile (5, C29H34N2S2)
Method A: A mixture of 0.458 g 4 (1mmol) and 2.23 g P2S5
(10 mmol) in 50 cm3 dry pyridine was heated under reflux for
6 h with stirring. The reaction mixture was cooled, and then
poured into ice, the separated solid was collected by filtration,
washed with H2O, dried under vacuum, and crystallized to
afford 0.35 g (75%) 5.
Method B: A mixture of 0.4g 3 (1mmol), 0.10 g ethyl cya-
nothioacetamide (1mmol) and 0.6 g ammonium acetate
(8mmol) in 30cm3 absolute ethanol was refluxed for 5 h.
After cooling, the formed product was collected by filtration,
washed with ethanol, dried and crystallized to give 0.38 g
1-(7-Isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a-deca-
hydrophenanthrene-1-yl)ethanone (2, C21H32O)
25
Mp 274–276ꢂC (AcOH); ½ꢁꢃD ¼ ꢁ16ꢄ10ꢁ1 deg cm2 gꢁ1
(c ¼ 1, MeOH); IR (film): ꢀꢀ¼ 1638 (C¼C), 1787 (C¼O),
25
cmꢁ1
;
1H NMR (DMSO-d6): ꢂ ¼ 1.11 (d, 2CH3), 1.16 (s,
(81%) 5. Mp 234–237ꢂC (AcOH); ½ꢁꢃD ¼ ꢁ41ꢄ10ꢁ1 deg
CH3), 1.23 (m, CH2), 1.29 (s, CH3), 1.36 (t, CH2), 1.44 (t,
CH2), 1.63 (t, CH2), 1.76 (s, CH), 1.92 (d, CH2), 1.96 (t, CH),
2.0 (t, CH2), 2.22 (s, CH3), 2.52 (m, CH), 5.57 (d, olefinic),
5.77 (d, olefinic) ppm; 13C NMR (DMSO-d6): ꢂ ¼ 16.5, 17.8,
18.0, 20.1, 20.2 (4C), 23.8, 28.1, 29.9, 31.0, 31.6, 33.8, 34.0,
41.1, 47.1, 47.8, 116.8 (olefin), 124.7 (olefin), 145.3 (olefin),
152.3 (olefin), 212.0 (C¼O) ppm; MS (EI, 70eV): m=z ¼ 300
[Mþ, 95] and at 167 [100, base peak].
cm2 gꢁ1 (c ¼ 1, MeOH); IR (film): ꢀꢀ¼ 3368 (NH), 2227
1
(CꢀN), 1238 (C¼S) cmꢁ1; H NMR (DMSO-d6): ꢂ ¼ 1.11
(d, 2CH3), 1.16 (s, CH3), 1.23 (m, CH2), 1.29 (s, CH3), 1.36
(t, CH2), 1.44 (t, CH2), 1.63 (t, CH2), 1.76 (s, CH), 1.92 (d,
CH2), 1.96 (t, CH), 2.0 (t, CH2), 2.52 (m, CH), 5.57 (d, olefinic),
5.77 (d, olefinic), 7.15–7.25 (m, thiophene-H), 8.58 (s, pyr-50-
H), 9.24 (s, NH, exchangeable with D2O) ppm; 13C NMR
(DMSO-d6): ꢂ ¼ 17.80, 18.00, 20.20, 20.66, 21.10, 23.80,
28.10, 29.90, 31.00, 32.20, 33.80, 35.10, 41.10, 47.10, 48.20,
108.00, 110.20, 116.80 (olefin), 117.20 (CN), 124.70 (olefin),
126.00, 127.23, 130.00, 136.00, 137.00, 145.30 (olefin), 152.30
(olefin), 170.00, 186.60 (thione) ppm; MS (EI, 70eV):
m=z ¼ 474 [Mþ, 15] and at 367 [100, base peak].
1-(7-Isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a-deca-
hydrophenanthrene-1-yl)-3-thien-2-ylpropenone
(3, C26H34OS)
25
Mp 266–267ꢂC (AcOH); ½ꢁꢃD ¼ ꢁ67ꢄ10ꢁ1 deg cm2 gꢁ1
(c ¼ 1, MeOH); IR (film): ꢀꢀ¼ 1634 (C¼C), 1791 (enone)
cmꢁ1
;
1H NMR (DMSO-d6): ꢂ ¼ 1.13 (d, 2CH3),1.18 (s,
(3-Cyano-6-(7-isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a-
decahydrophenanthrene-1-yl)-4-thien-2-yl-1,2-dihydro-
pyridine-2-ylsulfanyl}acetic acid ethyl ester
CH3), 1.23 (m, CH2), 1.27 (s, CH3), 1.37 (t, CH2), 1.44 (t,
CH2), 1.64 (t, CH2), 1.78 (s, CH), 1.92 (d, CH2), 1.96 (t, CH),
2.0 (t, CH2), 2.52 (m, CH), 5.57 (d, olefinic), 5.77 (d, olefinic),
6.63 (s, 1H-enone), 7.58 (s, 1H-enone), 7.31–7.66 (m, thio-
phene) ppm; MS (EI, 70eV): m=z ¼ 394 [Mþ, 100, base peak].
(6, C33H40N2O2S2)
To a mixture of 0.474 g 5 (1 mmol)and 0.18 g anhydrous K2CO3
(1mmol) in 25 cm3 N-dimethylformamide was stirred at room
temperature for 2 h, 0.18g ethyl chloroacetate (1.5 mmol) was
added with stirring. The reaction mixture was heated at 60ꢂC
for 2 h and after cooling poured into ice. The solid formed was
collected by filtration and crystallized to afford 0.34 g 6 (65%).
6-(7-Isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a-deca-
hydrophenanthrene-1-yl)-2-oxo-4-thien-2-yl-1,2-dihydro-
pyridine-3-carbonitrile (4, C29H34N2OS)
25
Mp 191–193ꢂC (dioxane); ½ꢁꢃD ¼ ꢁ49ꢄ10ꢁ1 deg cm2 gꢁ1
A mixture of 0.394 g 3 (1mmol), 0.95g ethyl cyanoacetate
(1mmol) and 0.6g ammonium acetate (8mmol) in 30cm3
absolute ethanol was refluxed for 5 h. After cooling, the
formed product was collected by filtration, washed with etha-
nol, dried and crystallized to give 0.41g (90%) 5. Mp 234–
(c ¼ 1, MeOH); IR (film): ꢀꢀ¼ 2218 (CꢀN), 1737 (C¼O, ester)
cmꢁ1; 1H NMR (DMSO-d6): ꢂ ¼ 1.13 (d, 2CH3), 1.17 (s, CH3),
1.22 (m, CH2), 1.28 (s, CH3), 1.35 (t, CH2), 1.38 (t, CH3), 1.43(t,
CH2), 1.61 (t, CH2), 1.77 (s, CH), 1.93 (d, CH2), 1.94 (t, CH),
1.96 (t, CH2), 2.55 (m, CH), 4.55 (q, CH2), 5.58 (d, olefinic),
4.70 (s, S–CH2), 5.78 (d, olefinic), 6.95–7.24 (m, thiophene-H),
8.60 (s, pyr-50-H) ppm; MS (EI, 70 eV): m=z ¼ 560 [Mþ, 18]
and at 524 [100, base peak].
25
237ꢂC (AcOH); ½ꢁꢃD ¼ ꢁ28 10ꢁ1 deg cm2 gꢁ1 (c ¼ 1,
MeOH); IR (film): ꢀꢀ¼ 3371 (NH), 2225 (CꢀN), 1638 (amide)
cmꢁ1
;
1H NMR (DMSO-d6): ꢂ ¼ 1.12 (d, 2CH3), 1.18 (s,
CH3), 1.25 (m, CH2), 1.29 (s, CH3), 1.35 (t, CH2), 1.45 (t,
CH2), 1.65 (t, CH2), 1.75 (s, CH), 1.92 (d, CH2), 1.95 (t, CH),
2.05 (t, CH2), 2.55 (m, CH), 5.55 (d, olefinic), 5.75 (d, olefin-
ic), 7.15–7.25 (m, thiophene-H), 8.55 (s, pyr-50-H), 9.55 (s,
NH, exchangeable with D2O) ppm; 13C NMR (DMSO-d6):
ꢂ ¼ 17.11, 18.0, 20.12, 20.56, 21.10, 23.18, 28.11, 29.91,
31.11, 32.11, 33.81, 34.8, 41.11, 47.11, 48.2, 108.0, 110.2,
116.8 (olefin), 117.2 (CN), 124.7 (olefin), 126, 127.23,
3-Amino-6-(7-isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,-
10,10a-decahydrophenanthrene-1-yl)-4-thien-2-yl-
thieno[2,3-b]pyridine-2-carboxylic acid ethyl ester
(7, C33H40N2O2S2)
A mixture of 0.562 g 6 (1 mmol) in 20cm3 sodium methoxide
solution (2%) was refluxed for 1 h on a water bath at 70ꢂC

Heterocyclic systems using abietic acid
703
with stirring. The reaction mixture was evaporated under
reduced pressure, the obtained residue was dissolved in
CH2Cl2, washed with H2O, 10 cm3 1 N HCl and then H2O.
The solvent was dried over anhydrous CaCl2, evaporated
2-(7-Isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a-deca-
hydrophenanthrene-1-yl)-6,7-dimethyl-4-thien-2-yl-7H-
9-thia-1,5,7-triazafluoren-8-one (10, C34H39N3OS2)
A solution of 0.55g 9 (1mmol) in 20cm3 DMF was stirred
with 0.19 g anhydrous K2CO3 (1mmol) for 10min at room
temperature, then 0.28g methyl iodide (2mmol) in 5 cm3
DMF were added. The reaction mixture was heated at 60ꢂC
for 4 h, after cooling poured into H2O, and the precipitate was
filtered off and crystallized to afford 0.35g (62%) 10. Mp
under reduced pressure, and the product was crystallized
25
to afford 0.53 g (92%) 7. Mp 308ꢂC (EtOH); ½ꢁꢃD
¼
ꢁ37ꢄ10ꢁ1 deg cm2 gꢁ1 (c ¼ 1, MeOH); IR (film): ꢀꢀ¼
3444–3310 (NH2), 1742 (C¼O, ester) cmꢁ1
;
1H NMR
(DMSO-d6): ꢂ ¼ 1.13 (d, 2CH3), 1.17 (s, CH3), 1.21 (m,
CH2), 1.31 (s, CH3), 1.36 (t, CH2), 1.42 (t, CH3), 1.48 (t,
CH2), 1.67 (t, CH2), 1.78 (s, CH), 1.92 (d, CH2), 1.96 (t,
CH), 2.0 (t, CH2), 2.58 (m, CH), 3.4 (CH2), 4.32 (brs, NH2,
exchangeable with D2O), 5.57 (d, olefinic), 5.77 (d, olefinic),
7.10–7.25 (m, thiophene-H), 8.62 (s, pyr-50-H) ppm; 13C
NMR (DMSO-d6): ꢂ ¼ 13.6, 17.8, 19.0, 20.2, 20.8, 21.21,
23.8, 28.1, 29.9, 31.0, 32.1, 33.8, 34.0, 41.1, 47.1, 48.6,
59.1, 116.8 (olefin), 122.8, 124.7 (olefin), 125.3, 127.16,
128.2, 129.1, 134.0, 136.0, 138.5, 142.6, 144.1, 145.3 (ole-
fin), 152.3 (olefin), 161.0 (CO), 163.9 ppm; MS (EI, 70 eV):
m=z ¼ 560 [Mþ, 4] and at 334 [100, base peak].
25
197–199ꢂC (DMF=H2O); ½ꢁꢃD ¼ ꢁ81ꢄ10ꢁ1 deg cm2 gꢁ1
1
(c ¼ 1, MeOH); IR (film): ꢀꢀ¼ 1668 (C¼O) cmꢁ1; H NMR
(DMSO-d6): ꢂ ¼ 1.10 (d, 2CH3), 1.14 (s, CH3), 1.23 (m, CH2),
1.27 (s, CH3), 1.36 (t, CH2), 1.41 (s, CH3), 1.44 (t, CH2), 1.63
(t, CH2), 1.76 (s, CH), 1.90 (d, CH2), 1.96 (t, CH), 1.98 (t,
CH2), 2.44 m, (CH), 2.48 (s, N–CH3), 5.51 (d, olefinic), 5.79
(d, olefinic), 6.96–7.15 (m, thiophene-H), 8.0 (s, pyr-50-H)
ppm; MS (EI, 70eV): m=z ¼ 569 [Mþ, 32] and at 504[100,
base peak].
2-(7-Isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a-deca-
hydrophenanthrene-1-yl)-6-methyl-7-phenyl-
2-(7-Isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a-deca-
hydrophenanthrene-1-yl)-6-methyl-4-thien-2-yl-7-oxa-
9-thia-1,5-diazafluoren-8-one (8, C33H36N2O2S2)
4-thien-2-yl-7H-9-thia-1,5,7-triazafluoren-8-one
(11, C39H41N3OS2)
A mixture of 0.55 g 8 (1mmol) and ꢅ0.1 g aniline (1 mmol)
in 50cm3 glacial acetic acid was heated under reflux for 6 h.
The reaction mixture was concentrated, poured onto ice, and
A mixture of 0.55 g 7 (1 mmol) in 100 cm3 ethanolic NaOH
(5%) was heated under reflux for 4 h. The solvent was evap-
orated under reduced pressure, the obtained sodium salt [A]
was dissolved in 100 cm3 acetic anhydride and refluxed
for 6 h. The reaction mixture was concentrated and allowed
to cool. The obtained solid was collected and crystallized
to afford 0.39 g (70%) 8. Mp 215–217ꢂC (AcOH=H2O);
the formed solid was filtered off and crystallized to afford
25
0.53g (85%) 11. Mp 312–314ꢂC (MeOH=H2O); ½ꢁꢃD
¼
ꢁ26ꢄ10ꢁ1 deg cm2 gꢁ1 (c ¼ 1, MeOH); IR (film): ꢀꢀ¼ 1678
(C¼O) cmꢁ1; 1H NMR (DMSO-d6): ꢂ ¼ 1.10 (d, 2CH3), 1.13
(s, CH3), 1.19 (s, CH3), 1.23 (m, CH2), 1.31 (s, CH3), 1.36 (t,
CH2), 1.44 (t, CH2), 1.60 (t, CH2), 1.74 (s, CH), 1.90 (d, CH2),
1.96 (t, CH), 1.98 (t, CH3), 2.50 (m, CH), 5.59 (d, olefinic),
5.81 (d, olefinic), 6.90–7.33 (m, 5 phenyl-H and thiophene-H),
8.42 (s, pyr-50-H) ppm; 13C NMR (DMSO-d6): ꢂ ¼ 16.9, 17.7,
18.8, 20.22 20.7, 21.12, 23.7, 28.2, 29.8, 31.0, 32.1, 33.7, 34.1,
41.2, 47.1, 48.20, 116.9 (olefin), 120.2, 120.5, 121.0, 122.8,
124.6 (olefin), 125.3 (2C–Ar), 127.5 (2C–Ar), 128.7, 129.0,
136.0, 137.1, 138.2, 144.1, 142.6, 145.8 (olefin), 146, 152.2
(olefin), 163.9, 164.4, 165 ppm; MS (EI, 70eV): m=z ¼ 631
[Mþ, 100, base peak].
25
½ꢁꢃD ¼ ꢁ34ꢄ10ꢁ1 deg cm2 gꢁ1 (c ¼ 1, MeOH); IR (film):
1
ꢀꢀ¼ 1736 (C¼O) cmꢁ1; H NMR (DMSO-d6): ꢂ ¼ 1.10 (d,
2CH3), 1.14 (s, CH3), 1.25 (s, CH2), 1.29 (s, CH3), 1.36 (m,
CH2), 1.38 (s, CH3), 1.44 (t, CH2), 1.63 (t, CH2), 1.76 (s,
CH), 1.92 (d, CH2), 1.96 (t, CH), 2.09 (t, CH2), 2.56 (m,
CH), 5.57 (d, olefinic), 5.77 (d, olefinic), 6.98–7.25 (m,
thiophene-H), 8.20–8.26, 8.55 (s, pyr-50-H) ppm; MS (EI,
70 eV): m=z ¼ 556 [Mþ, 22] and at 353 [100, base peak].
2-(7-Isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a-deca-
hydrophenanthrene-1-yl)-6-methyl-4-thien-2-yl-7H-
2-(7-Isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a-deca-
hydrophenanthrene-1-yl)-6-methyl-4-thien-2-yl-[(thien-
2-ylmethylene)amino]-7H-9-thia-1,5,7-triazafluoren-8-one
(12, C33H38N4OS2)
9-thia-1,5,7-triazafluoren-8-one (9, C33H37N3OS2)
A mixture of 0.55g 8 (1mmol) and 0.6g ammonium acetate
(8mmol) in 100 cm3 glacial acetic acid was refluxed for 6 h.
The reaction mixture was concentrated under reduced pres-
sure, then poured into H2O, and the solid formed was col-
lected by filtration and crystallized to afford 0.39 g (70%) 9.
A mixture of 0.454 g 8 (1mmol) and 0.4cm3 hydrazine hy-
drate (8mmol) in 100 cm3 absolute ethanol was refluxed for
4 h. After cooling the solid formed was collected and crystal-
lized to afford 0.49g (87%) 12. Mp 350ꢂC (AcOH=H2O);
25
Mp 216–218ꢂC (EtOH=H2O); ½ꢁꢃD ¼ ꢁ13 10ꢁ1 deg cm2 gꢁ1
(c ¼ 1, MeOH); IR (film): ꢀꢀ¼ 3428 (NH), 1670 (C¼O)
25
cmꢁ1
;
1H NMR (DMSO-d6): ꢂ ¼ 1.11 (d, 2CH3), 1.14
½ꢁꢃD ¼ ꢁ39ꢄ10ꢁ1 deg cm2 gꢁ1 (c ¼ 1, MeOH); IR (film):
ꢀꢀ¼ 3373–3300 (NH2), 1678 (C¼O) cmꢁ1
;
1H NMR
(s, CH3), 1.23 (m, CH2), 1.29 (s, CH3), 1.36 (t, CH2),
1.40 (s, CH3), 1.44 (t, CH2), 1.61 (t, CH2), 1.77 (s, CH),
1.92 (d, CH2), 1.96 (t, CH), 2.0 (t, CH2), 2.51 (m, CH), 5.53
(d, olefinic), 5.77 (d, olefinic), 7.1–7.25 (m, thiophene-H),
8.61 (s, pyr-50-H), 8.39 (s, NH exchangeable with D2O)
ppm; MS (EI, 70 eV): m=z ¼ 555 [Mþ, 38] and at 211
[100, base peak].
(DMSO-d6): ꢂ ¼ 1.10 (d, 2CH3),1.13 (s, CH3), 1.18 (s, CH3),
1.23 (m, CH2), 1.29 (s, CH3), 1.36 (t, CH2), 1.48 (t, CH2), 1.61
(t, CH2), 1.74 (s, CH), 1.90 (d, CH2), 1.95 (t, CH), 1.99 (t,
CH2), 2.50 (m, CH), 4.35 (brs, NH2, exchangeable with D2O),
5.63 (d, olefinic), 5.71 (d, olefinic), 7.00–7.25 (m, thiophene-
H), 8.56 (s, pyr-50-H) ppm; 13C NMR (DMSO-d6): ꢂ ¼ 14.4,

704
M. M. Abdulla
17.1, 18.0, 20.3, 20.7, 21.1, 23.8, 28.2, 30.0, 31.0, 32.6, 33.8,
34.1, 41.1, 47.1, 48.2, 116.7 (olefin), 120.1, 122.8, 124.7
(olefin), 125.3, 127.15, 128.6, 136.1, 137.17, 142.6, 144.1,
145.7 (olefin), 146.8, 152.7 (olefin), 163.9, 164.5, 167.8 ppm;
MS (EI, 70 eV): m=z ¼ 570 [Mþ, 58] and at 312 [100, base
peak].
All animals were obtained from the Animal House Colony,
Research Institute of Ophthalmology, Giza, Egypt. Foot paw
edema was induced by subplantar injection of 0.05cm3 of a
1% suspension of carrageenan in saline into the plantar tissue
of one hind paw. An equal volume of saline was injected to the
other hand paw and served as control. Four hours after drug
administration the animals were decapitated, blood was col-
lected, and the paws were rapidly excised. The average weight
of edema was examined for the treated as well as the control
group and the percentage inhibition of weight of edema was
also evaluated. Prednisolone (5mg=kg) was employed as
standard reference against which the tested compounds were
compared.
7-Amino-2-(7-isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,
10a-decahydrophenanthrene-1-yl)-6-methyl-4-thien-2-yl-7H-
9-thia-1,5,7-triazafluoren-8-one (13, C38H40N4OS3)
A mixture of 0.57g 12 (1mmol) and 0.12g thiophene-2-car-
baldehyde (1mmol) in 25cm3 absolute ethanol was refluxed
for 6 h. The obtained solid was filtered off, washed with
ethanol, and crystallized to afford 0.63 g (96%) 13. Mp
Estimation of plasma prostaglandin E2 (PGE2)
25
289ꢂC (EtOH=H2O); ½ꢁꢃD ¼ ꢁ28ꢄ10ꢁ1 deg cm2 gꢁ1 (c ¼ 1,
Heparinized blood samples were collected from rats (n ¼ 8),
plasma was separated by centrifugation at 12,000 g for 2 min
at 40ꢂC, immediately frozen, and stored at 20ꢂC until use. The
design correlate EIA prostaglandin E2 (PGE2) kit (Aldrich,
Steinheim, Germany) is a competitive immuno assay for the
quantitative determination of PGE2 in biological fluids. The
kit uses a monoclonal antibody to PGE2 to bind, in a compet-
itive manner, the PGE2 in the sample after a simultaneous
incubation at room temperature. The excess reagents were
washed away and the substrate was added, after a short incu-
bation time the enzyme reaction was stopped, and the yellow
color generated was read on a microplate reader DYNATech,
MR 5000 at 405 nm (Dynatech Industries Inc., McLean, VA,
USA). The intensity of the bound yellow color is inversely
proportional to the concentration of PGE2 in either standard or
samples.
1
MeOH); IR (film): ꢀꢀ¼ 1688 (C¼O), 1660 (C¼N) cmꢁ1; H
NMR (DMSO-d6): ꢂ ¼ 1.10 (d, 2CH3), 1.13 (s, CH3),1.19 (s,
CH3), 1.23 (m, CH2), 1.27 (s, CH3), 1.37 (t, CH2), 1.43 (t,
CH2), 1.61 (t, CH2), 1.78 (s, CH), 1.90 (d, CH2), 1.94 (t, CH),
1.96 (t, CH2), 2.50 (m, CH), 5.60 (d, olefinic), 5.80 (d, olefin-
ic), 7.10–7.40 (m, thiophene-H þ CH¼N), 8.50 (s, pyr-50-H)
ppm; MS (EI, 70eV): m=z ¼ 664 [Mþ, 100, base peak].
1-[2-(7-Isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a-
decahydrophenanthrene-1-yl)-6-methyl-4-thien-2-yl-8H-9-
thia-1,5,7-triazafluoren-7-yl]-3-phenyl-thiourea
(14, C40H43N5OS3)
A mixture of 0.57 g 12 (1 mmol) and 0.14 g phenyl isothiocya-
nate (1mmol) in 50 cm3 dry dioxane containing 2 cm3 trieth-
ylamine was heated under reflux for 10 h. The solvent
was evaporated under reduced pressure, the obtained residue
was solidified with n-hexane. The obtained solid was filtered
off, washed with diethyl ether, dried and crystallized to afford
References
25
0.53g (75%) 14. Mp 213–214ꢂC (AcOH); ½ꢁꢃD ¼ ꢁ89ꢄ
10ꢁ1 deg cm2 gꢁ1 (c ¼ 1, MeOH); IR (film): ꢀꢀ¼ 3331–3258
(NH), 1675 (C¼O), 1242 (C¼S) cmꢁ1; 1H NMR (DMSO-d6):
ꢂ ¼ 1.11 (d, 2CH3), 1.16 (s, CH3), 1.19 (s, CH3), 1.23 (m,
CH2), 1.29 (s, CH3), 1.36 (t, CH2), 1.44 (t, CH2), 1.63 (t,
CH2), 1.76 (s, CH), 1.92 (d, CH2), 1.96 (t, CH), 2.0 (t, CH2),
2.52 (m, CH), 4.17–4.27 (bs, 2 NH–CS, exchangeable with
D2O), 5.57 (d, olefinic), 5.77 (d, olefinic), 6.97–7.57 (m, thio-
phene-H and phenyl-H), 8.47 (s, pyr-50-H) ppm; MS (EI,
70eV): m=z ¼ 705 [Mþ, 39] and at 546 [100, base peak].
1. Attia A, Abdel-Salam OI, Abo-Ghalia MH, Amr AE
(1995) Egypt J Chem 38:543
2. Amr AE, Ashraf MM, Salwa FM, Nagla AA, Hammam
AG (2006) Bioorg Med Chem 14:5481
3. Amr AE, Abdel-Latif NA, Abdalla MM (2006) Acta
Pharm 56:203
4. Amr AE, Abdalla MM (2006) Bioorg Med Chem 14:4341
5. Abo-Ghalia MH, Amr AE (2004) Amino Acids 26:283
6. Amr AE, Abdel-Salam OI, Attia A, Stibor I (1999)
Collect Czech Chem C 64:288
7. Attia A, Abdel-Salam OI, Amr AE (2000) Egypt J Chem
43:297
Pharmacological screening
8. Brana MF, Castellano JM, Moran M, Perez de Vega MJ,
Qian XD, Romerdahl CA, Keihauer G (1995) Eur J Med
Chem 30:235
9. Chakrabarti JK, Horsman L, Hotten TM, Pullar IA,
Tupper DE, Wright FC (1980) J Med Chem 23:878
10. Ram VJ, Pandey HK, Vlietinck AJ (1981) J Heterocycl
Chem 18:1277
Determination of acute toxicity (LD50
)
The LD50 was determined by using rats. They were injected
with different increasing doses of the synthesized compounds.
The dose that killed 50% of the animal was calculated accord-
ing to Austen et al. [26].
Anti-inflammatory activity
11. Fahmy HH, El-Eraqy W (2001) Arch Pharm Res 24:171
12. DeClercq E (1986) Anticancer Res 6:549
13. DeClercq E (1986) J Med Chem 29:156
14. Hammam AG, Sharaf M, Abdel-Hafez NA (2001) Ind J
Chem 40B:213
Carrageenan-induced edema (rats paw test)
Groups of adult male albino rats (150–180 g), each of eight
animals were orally dosed with tested compounds at a dose
level of 25–50 mg=kg one hour before carrageenan challenge.

Heterocyclic systems using abietic acid
705
15. Hammam AG, Fahmy AFM, Amr AE, Mohamed AM
(2003) Ind J Chem 42B:1985
21. Amr AE, Abou-Galia MH, Abdulla MM (2006) Z Nat-
urforsch 61b:1335
16. Amr AE, Hegab MI, Ibrahiem AA, Abdulla MM (2003)
Monatsh Chem 134:1395
22. Amr AE, Abdulla MM (2006) Arch Pharm Chem Life Sci
339:88
17. Nehad AA, Amr AE, Alhusain AI (2006) Monatsh Chem
(Accepted 23-11-2006)
18. Amr AE, Abdel-Latif NA, Abdalla MM (2006) Bioorg
Med Chem 14:273
19. Amr AE, Sayed HH, Abdulla MM (2005) Arch Pharm
Chem Life Sci 338:433
20. Amr AE (2005) Z Naturforsch 60b:90
23. Amr AE (2000) Ind J Heterocycl Chem 10:49
24. Winter CA, Risely EA, Nuss GW (1962) Proc Soc Exp
Bio Med 111:541
25. Herrmann F, Lindemann A, Gamss J, Mertelsmann R
(1999) Eur J Immunol 20:2513
26. Austen KF, Brocklehurst WE (1961) J Exp Med
113:521