Novel polyazaheterocyclic systems: Synthesis, antitumor, and antimicrobial activities

Article abstract of DOI:10.1007/s12272-010-1102-8

A series of new polyazaheterocyclic ring systems was synthesized via the reaction of enaminone 5 with active methylene compounds, hydrazine hydrate, hydroxylamine, and heterocyclic amines. The structures of the newly synthesized compounds were substantiated on the basis of spectral data and elemental analyses. The antitumor activity of the enaminone 5 against the human breast cell line MCF-7, the liver carcinoma cell line HEPG2-1, and HELA cells was determined. In addition, the antimicrobial activity of some selected products was evaluated.

Full text of DOI:10.1007/s12272-010-1102-8

Arch Pharm Res Vol 33, No 11, 1721-1728, 2010
DOI 10.1007/s12272-010-1102-8
Novel Polyazaheterocyclic Systems: Synthesis, Antitumor, and Anti-
microbial Activities
Sayed M. Riyadh, Thoraya A. Farghaly, and Sobhi M. Gomha
Department of Chemistry, Faculty of Science, University of Cairo, Giza, 12613, Egypt
(Received November 23, 2009/Revised May 16, 2010/Accepted May 16, 2010)
A series of new polyazaheterocyclic ring systems was synthesized via the reaction of
enaminone
5 with active methylene compounds, hydrazine hydrate, hydroxylamine, and
heterocyclic amines. The structures of the newly synthesized compounds were substantiated
on the basis of spectral data and elemental analyses. The antitumor activity of the enaminone
5
against the human breast cell line MCF-7, the liver carcinoma cell line HEPG2-1, and
HELA cells was determined. In addition, the antimicrobial activity of some selected products
was evaluated.
Key words: Pyrazolo[3',4':4,5]pyrimido[1,6-
b][1,2,4]triazepin-5-one, Enaminone, Antitumor
activity, Antimicrobial activity
penta-, and hexazaheterocyclic ring systems incor-
INTRODUCTION
porating pyrazolo[3,4-d]pyrimidine and fused [1,2,4]
Pyrazolo[3,4-d]pyrimidines, such as glycogen syn- triazepines and evaluated their antitumor and anti-
thase kinase-3 inhibitors (GSK-3) (Peat et al., 2004) microbial activities.
and adenosine receptor antagonists (Baraldi et al.,
1999, 2000; Baraldi and Borea, 2000; Gomtsyan et al.,
2004), have a pivotal role in modern medicinal chem-
istry. These compounds have antimicrobial (Ballell et
MATERIALS AND METHODS
Melting points were determined on a Gallenkamp
al., 2007), antitumor (Anderson et al., 1990), and anti- apparatus and are uncorrected. IR spectra were re-
bacterial activities (Ballell et al., 2007) as well as known corded in a Pye-Unicam SP300 instrument in potas-
antiviral activity against hepatitis-A virus (HAV) and sium bromide discs. 1H NMR spectra were recorded in
herpes simplex virus (HSV-1) (Rashad et al., 2008). a Varian Mercury VXR-300 spectrometer 300 MHz in
Recently, there has been considerable attention focused DMSO-d6 and the chemical shifts were related to TMS
on the synthesis of fused [1,2,4]triazepines because of as standard solvent. Mass spectra were recorded in a
their potential pharmacological activity (Lamsabhi et GCMS-QP 1000 EX Shimadzu spectrometer, the ion-
al., 2002) as immunomodulating agents (Rezessy et izing voltage was 70 eV. Elemental analyses were
al., 1999). An interest in the varied biological activities carried out at the Microanalytical Laboratory of Cairo
of pyrazolo[3,4-
d]pyrimidines and fused [1,2,4]triaze- University, Giza, Egypt. Antitumor activity was evalu-
pines and in continuation of our research in the con- ated by the National Institute of Cancer, Biology De-
struction of new polyheterocyclic ring systems (Mosselhi partment, Cairo University, Egypt.
et al., 2004; Ahmed and Farghaly, 2009; Farghaly
and Riyadh, 2009; Shawali et al., 2009; Farghaly et
al., 2010), we have synthesized a new series of tetra-,
Synthesis of 1,3,7-triphenyl-1
pyrimido[1,6- ][1,2,4]triazepin-5(6
A mixture of 5-amino-1,3-diphenyl-4-iminopyrazolo
[3,4- ]pyrimidine ( ) (3.02 g, 10 mmol) and ethyl ben-
zoylacetate ( ) (3 g, 15 mmol) was heated under reflux
for 2 h. After cooling, the solid precipitate was collect-
ed and crystallized from an ethanol/dioxane mixture
H
-pyrazolo[3',4':4,5]
b
H)-one (3)
b
1
Correspondence to: Thoraya A. Farghaly, Department of Chem-
istry, Faculty of Science, University of Cairo, Giza, 12613, Egypt
Tel: 20-2-0106745618
2
E-mail: thoraya-f@hotmail.com
1721

1722
S. M. Riyadh et al.
(1:1) as pale yellow crystals [98% yield], mp 194-196oC; CH2), 7.21-8.26 (m, 15H, Ar-H), 8.64 (s, 1H, 4-H-pyri-
1
IR (KBr)
υ
: 1680 (C=O) cm-1; H NMR (DMSO-d6):
δ
dine), 9.68 (s, 1H, pyrimidine-H); MS, m/z (%): 551 (M+,
4.81 (s, 2H, CH2), 7.44-8.65 (m, 15H, Ar-H), 9.64 (s, 1H, 60), 478 (70), 77 (100). Anal. Calcd. for C33H25N7O2
pyrimidine-H); MS, m/z (%): 431 (M++1, 2), 430 (M+, 20), (551.21): C, 71.86; H, 4.57; N, 17.78. Found: C, 71.73;
105 (100), 77 (80). Anal. Calcd. for C26H18N6O (430.15): H, 4.39; N, 17.61%.
C, 72.55; H, 4.12; N, 19.52. Found: C, 72.33; H, 4.24;
N, 19.41%.
Ethyl 1,3,6,9-tetraphenyl-1
mido[1,6- ]pyrido[2,3- ][1,2,4]triazepine-7-carboxy-
late (8c)
Pale yellow crystals [86% yield], mp >320oC; IR (KBr)
υ: 1708 (C=O) cm-1; 1H NMR (DMSO-d6):
1.21 (t,
(4.3 g, 10 mmol) and dimethylforma- 7 Hz, 3H, CH3), 4.15 (q, = 7 Hz, 2H, CH2), 7.11-8.27
H-pyrazolo[3',4':4,5]pyri-
b
e
Synthesis of 1,3,7-triphenyl-6-[(dimethylamino)
methylene]-1
][1,2,4]triazepin-5-one (5)
A mixture of
H-pyrazolo[3',4':4,5] pyrimido[1,6-
δ
J =
b
3
J
mide-dimethylacetal (10 mL) was refluxed for 20 min. (m, 20H, Ar-H), 8.65 (s, 1H, 4-H-pyridine), 9.76 (s, 1H,
After cooling, the precipitate was collected by filtration pyrimidine-H); MS, m/z (%): 613 (M+, 40), 540 (20), 77
and crystallized from dioxan as: yellow crystals [96% (100). Anal. Calcd. for C38H27N7O2 (613.22): C, 74.37;
yield], mp 244-246oC; IR (KBr)
NMR (DMSO-d6):
15H, Ar-H), 7.54 (s, 1H, CH=), 9.72 (s, 1H, pyrimidine-
H); MS, m/z (%): 486 (M++1, 3), 485 (M+, 20), 408 (3),
380 (5), 115 (3), 105 (37), 77 (100). Anal. Calcd. for
C29H23N7O (485.20): C, 71.74; H, 4.77; N, 20.19. Found:
C, 71.61; H, 4.66; N, 20.22 %.
υ
: 1648 (C=O) cm-1; 1H H, 4.43; N, 15.98. Found: C, 74.43; H, 4.32; N, 15.81%.
δ
3.81 (s, 6H, 2CH3), 7.48-7.87 (m,
Synthesis of 1,3,8-triphenyl-1,6-dihydro-pyrazolo
[3',4':4,5]pyrimido[1,6-b]pyrazolo[3,4-e][1,2,4]tri-
azepine (11)
A mixture of
5 (0.485 g, 1 mmol) with hydrazine hydr-
ate (2 mL) in absolute ethanol (15 mL) was heated
under reflux for 10 h. After cooling, the reaction mix-
ture was poured into ice cold water and the solid pro-
duct was collected and crystallized from dioxane as
Synthesis of pyrazolo[3',4':4,5]pyrimido[1,6-
b]
pyrido[2,3- ][1,2,4]triazepines (8a-c)
e
Ammonium acetate (0.156 g, 2 mmol) was added to pale yellow crystals [80% yield], mp 152-154oC; IR
a solution of
5 (0.485 g, 1 mmol) and appropriate active (KBr) υ δ 7.18-
: 3231 (NH) cm-1; 1H NMR (DMSO-d6):
methylene compounds (6a-c) (1 mmol of each) in acetic 8.42 (m, 15H, Ar-H), 8.94 (s, 1H, 5-H-pyrazole), 9.69 (s,
acid (20 mL). The reaction mixture was heated under 1H, pyrimidine-H), 10.42 (s, 1H, NH); MS, m/z (%):
reflux for 5 h. After cooling, the reaction mixture was 454 (M+, 20), 378 (30), 287 (60), 77 (100). Anal. Calcd.
poured into ice cold water and the solid product formed for C27H18N8 (454.17): C, 71.35; H, 3.99; N, 24.66.
was collected by filtration and crystallized from an Found: C, 71.23; H, 3.81; N, 24.52%.
ethanol/dioxane mixture (1:1). The physical constants
together with the spectral data for products 8a-c are
Synthesis of 1,3,8-triphenyl-1H-pyrazolo[3',4':4,5]
shown below.
pyrimido[1,6-b]isoxazolo[5,4-e][1,2,4]triazepine
(12)
1,3,9-Triphenyl-6-methyl-7-acetyl-1
H
-pyrazolo[3',4':
Hydroxylamine hydrochloride (0.07g, 1 mmole) and
anhydrous potassium carbonate (0.138 g, 1 mmole)
4,5]pyrimido[1,6-
(8a)
b]pyrido[2,3-e][1,2,4]triazepine
was added to a solution of
5 (0.485 g, 1 mmol) in abso-
Yellow crystals [79% yield], mp 310-312oC; IR (KBr) υ: lute ethanol (15 mL), and the mixture was refluxed for
1
1694 (C=O) cm-1; H NMR (DMSO-d6):
δ 2.71 (s, 3H, 5 h. The solid formed was collected by filtration and
CH3), 2.79 (s, 3H, COCH3), 7.11-8.36 (m, 15H, Ar-H), crystallized from dioxane/ethanol (1:1) to give pale
8.73 (s, 1H, 4-H-pyridine), 9.79 (s, 1H, pyrimidine-H); yellow crystals [75% yield], mp 256-258oC; IR (KBr) υ:
MS, m/z (%): 521 (M+, 3), 430 (6), 419 (3), 105 (100), 83 1594 (C=N) cm-1; 1H NMR (DMSO-d6):
δ 7.43-8.61 (m,
(4), 77 (82). Anal. Calcd. for C32H23N7O (521.20): C, 73.69; 15H, Ar-H), 9.24 (s, 1H, 5-H-isoxazole), 9.72 (s, 1H,
H, 4.44; N, 18.80. Found: C, 73.53; H, 4.34; N, 18.71%.
pyrimidine-H); MS, m/z (%): 455 (M+, 20), 379 (30),
288 (60), 77 (100). Anal. Calcd. for C27H17N7O (455.15):
Ethyl 6-methyl-1,3,9-triphenyl-1
4,5]pyrimido[1,6- ]pyrido[2,3- ] [1,2,4]triazepine- N, 21.72%.
7-carboxylate (8b)
Yellow crystals [83% yield], mp 300-302oC; IR (KBr) υ:
1712 (C=O) cm-1; 1H NMR (DMSO-d6):
1.34 (t, = 7
Hz, 3H, CH3), 2.72 (s, 3H, CH3), 4.19 (q, = 7 Hz, 2H,
H-pyrazolo[3',4': C, 71.20; H, 3.76; N, 21.53. Found: C, 71.28; H, 3.85;
b
e
Reaction of enaminone 5 with heterocyclic a-
mines
A mixture of 5 (0.485 g, 1 mmol) with heterocyclic
δ
J
J

Synthesis Heterocyclic Ring Systems Enaminone Pyrazolopyrimidotriazepine
1723
amines (1 mmole of each) in acetic acid (20 mL) was between the surviving fraction and drug concentration
heated under reflux for 10 h. After cooling, the reac- was plotted to get the survival curve of each tumor
tion mixture was poured into ice cold water and the cell line after treatment with the specified compound
solid product was collected and crystallized from and the IC50 was calculated (Fig. 1, 2, and 3).
dioxane.
RESULTS AND DISCUSSION
1,3,11-Triphenyl-1
6- ][1,2,4]triazolo[3',4':2,1]pyrimido[6,5-
azepine (15)
Pale yellow crystals [80% yield], mp 280-283oC; IR to react with ethyl benzoylacetate
(KBr) υ: 1604 (C=N) cm-1; 1H NMR (DMSO-d6):
7.40- The designed product of this reaction was 1,3,7-triphenyl-
8.29 (m, 15H, Ar-H), 8.73 (s, 1H, 5-H-triazole), 9.45 (s, -pyrazolo[3',4':4,5]pyrimido[1,6- ][1,2,4]triazepin-5
)-one ( ) or its isomeric structure 1,3,5-triphenyl-
-pyrazolo[3',4':4,5]pyrimido[1,6- ]triazepin-7(8 )-one
) (Scheme 1). MS and elemental analyses data of the
isolated product were consistent with each of the
H-pyrazolo[3',4':4,5]pyrimido[1,
b
e][1,2,4]tri-
5-Amino-1,3-diphenyl-4,5-dihydro-4-imino-1
[3,4- ]pyrimidine ( ) (Shawali et al., 1994) was allowed
under heating.
H-pyrazolo
d
1
2
δ
1H
b
1H, pyrimidine-H), 9.63 (s, 1H, pyrimidine-H); MS, (6
H
3
m/z (%): 506 (M+, 60), 429 (30), 220 (10), 77 (100).
Anal. Calcd. for C29H18N10 (506.17): C, 68.77; H, 3.58;
N, 27.65. Found: C, 68.63; H, 3.71; N, 27.51%.
1H
b
H
(4
1
isomeric structures
3
and
4
, while, H NMR spectra
1,3,13-Triphenyl-1
6- ]benzimidazo[1',2':1,2]pyrimido[6,5-
azepine (17)
H
-pyrazolo[3',4':4,5]pyrimido[1, revealed singlet signal at
δ
4.80 ppm assignable for
b
e][1,2,4]tri- 2H protons at position 6 (CH2CO). In addition, the
D2O experiment revealed the absence of a NH proton
Pale yellow crystals [82% yield], mp > 320oC; IR (KBr) signal, which discarded isomeric structure
4. These re-
1
υ: 1601 (C=N) cm-1; H NMR (DMSO-d6):
δ 7.13-8.47 sults are consistent with our previous report (Shawali
(m, 19H, Ar-H), 9.41 (s, 1H, pyrimidine-H), 9.60 (s, 1H, et al., 2009) on the reaction of
1 with ethyl acetoacetate.
pyrimidine-H); MS, m/z (%): 555 (M+, 40), 478 (30), 77 In addition, previous literature reports demonstrated
(100). Anal. Calcd. for C34H21N9 (555.19): C, 73.50; H, that, the reaction of imino-aminoheterocycles with ethyl
3.81; N, 22.69. Found: C, 73.61; H, 3.61; N, 22.50%.
acetoacetate proceeded by concurrent elimination of
ethanol (=NH, COOEt) and condensation of water
molecules (N-NH2, CO) (Essassi et al., 1975; Romano
et al., 1988; Baraldi et al., 2004; Hassan et al., 2006).
It has been reported that the presence of the basic
1,3,11-Triphenyl-1
[3',4':4,5]pyrimido[1,6-
[4,5- ][1,2,4]triazepine-5(6
Pale yellow crystals [80% yield], mp 200-202oC; IR side chain of
(KBr) υ: 1652 (C=O) cm-1; 1H NMR (DMSO-d6):
7.23-
H
-7,8-dihydro-7-thioxo-pyrazolo
]pyrimido[4',5':2,3]pyrido
)-one (19)
b
e
H
N,N-dialkylaminoalkyl group enhances
δ
8.37 (m, 15H, Ar-H), 9.28 (s, 1H, pyrimidine-H), 9.58
(s, 1H, pyrimidine-H), 10.32 (s, 1H, NH), 10.54 (s, 1H,
NH); MS, m/z (%): 565 (M+, 40), 488 (30), 103 (50), 77
(100). Anal. Calcd. for C31H19N9OS (565.14): C, 65.83;
H, 3.39; N, 22.29; S, 5.67. Found: C, 65.67; H, 3.51; N,
22.42; S, 5.53%.
Cytotoxic activity
The method applied is similar to that reported by
Skehan et al. (1990) using Sulfo-Rhodamine-B stain
(SRB). Cells were plated in 96-multiwell plates (104
cells/well) for 24 h before treatment with the tested
compound to allow attachment of cells to the plate
walls. Different concentrations of the compounds (0,
2.5, 5, and 10 µg/mL) were added to the cell monolayer
in triplicate wells and incubated for 48 h in 5% CO2 at
37oC. After 48 h, the cells were fixed, washed, and
stained with SRB stain, excess stain was removed by
washing with acetic acid and the attached stain was
recovered with tris-EDTA buffer, color intensity was
then measured in an ELISA reader. The relation
Scheme 1. Synthesis of 1,3,7-triphenyl-6-[(dimethylamino)
methylene]-1 -pyrazolo[3',4':4,5]pyrimido[1,6- ][1,2,4]triaze-
pin-5-one (
H
b
5)

1724
S. M. Riyadh et al.
the DNA affinity (Ducrocq et al., 1980) and the anti- suggest that pyrazolo[3',4':4,5]pyrimido[1,6-
cancer activity against human breast cell MCF-7 line 3- ][1,2,4]triazepine derivatives, 8a-c, were obtained
(Shawali et al., 2009) of this drug. This finding pro- via nucleophilic displacement of active methylene to a
mpted us to condense 1,3,7-triphenyl-1 -pyrazolo[3',4': dimethylamino group followed by concurrent elimina-
4,5]pyrimido[1,6- ][1,2,4]triazepin-5(6 )-one ( ) with tion of a water molecule from non-isolable interme-
dimethylformamide-dimethylacetal (DMF-DMA) to diates 7a-c (route 1) (Scheme 2). The other isomeric
obtain 1,3,7-triphenyl-6-[(dimethylamino)methylene]- structures, pyrazolo[3',4':4,5]pyrimido[1,6- ]pyrido[4,
-pyrazolo[3',4':4,5]pyrimido[1,6- ][1,2,4]triazepin-5- 3- ][1,2,4]triazepines, 10a-c, were obtained via con-
one ( ) (cf. Scheme 1). Elemental analyses and spec- densation of active methylene with the carbonyl group
tral data were in complete accordance with the as- of enaminone followed by elimination of dimethyl-
b]pyrido[2,
e
H
b
H
3
b
1H
b
e
5
1
signed structure
trum of compound
3.81 and 7.54 ppm, which is characteristic for N,N
5. For example, the H NMR spec- amine from intermediates 9a-c (route 2). The actual
5
revealed two singlet signals at
δ
structures of these products were assigned 8a-c rather
1
-
than 10a-c based on their H NMR spectra which
dimethylamino and the exocyclic C=CH protons, re- showed characteristic singlet signals at
spectively (Dawood, 2005). The enaminone was as- ppm that were assigned for the pyridine-4H of com-
signed the
-configuration based on its 1H NMR spec- pounds 8a-c (Al-Saleh et al., 2004).
trum which revealed that the exocyclic C=CH proton Reaction of the enaminone with hydrazine hydr-
-isomer (5A), ate in absolute ethanol resulted in the formation of a
-isomer (5B) of the analogous structure single product, 1,3,8-triphenyl-1,6-dihydro-pyrazolo[3',
δ 8.64-8.73
5
E
5
signal at
while the
δ 7.54 ppm correlated for E
Z
was reported to appear at
1972).
δ 6.9 ppm (Bennett et al., 4':4,5]pyrimido[1,6-b]pyrazolo[3,4-e][1,2,4]triazepine (11),
as demonstrated by TLC (Scheme 3). For example, 1H
Reactions of enaminone
5
with active methylene NMR spectrum of 11 showed three characteristic singlet
compounds, namely, acetylacetone, ethyl acetoacetate signals at
δ 8.94, 9.69 and 10.42 ppm assignable to
and ethyl benzoylacetate in glacial acetic acid in the pyrazole-H, pyrimidine-H and NH (Grothaus and Dains,
presence of ammonium acetate were investigated. We 1936; Anderson and Muchmore, 1995; Abdallah et al.,
2005), respectively. It is assumed that compound 11 is
formed via the initial addition of the amino group in
hydrazine to the enamine double bond followed by eli-
mination of dimethylamine and water molecules to
give the final isolable product 11. Similarly, the en-
aminone
5 reacts with hydroxylamine hydrochloride
in absolute ethanol in the presence of anhydrous potas-
sium carbonate to give one isolable product, pyrazolo
[3',4':4,5]pyrimido[1,6-b]isoxazolo[5,4-e][1,2,4]triazepine
derivative 12 (cf. Scheme 3). Structure 12 was assigned
for the reaction product based on the 1H NMR spectrum
Scheme 2. Reaction of enaminone
compounds 6a-c
5
with active methylene
Scheme 3. Reaction of enaminone 5 with hydrazine
hydrate and hydroxyl amine

Synthesis Heterocyclic Ring Systems Enaminone Pyrazolopyrimidotriazepine
1725
in which a resonance for H-3 of isoxazole appeared, as mL, respectively (Fig. 2 and 3). The IC50 value indicat-
expected, at 8.50 ppm. The other isomeric structure ed that compound is a more active cytotoxic agent
13 was ruled out because H-5 of isoxazole would be against the human breast cell line MCF-7.
expected to resonate at 9.20 ppm (Dominguez et al.,
δ
5
δ
1996; Hassanien et al., 2004).
Antimicrobial activity
As previously reported enaminones can be used as
Some of the prepared compounds (namely 3, 5, 8a,
potential precursors for fused heterocyclic systems 11
when reacting with heterocyclic amines (Riyadh et al., (in nutrient agar broth) and antifungal activity (in
2008). Thus, treatment of enaminone with 3-amino- Dox's medium and Saboured's agar) by the agar diffu-
, 12, and 15) were screened for antibacterial activity
5
triazole 14, 2-aminobenzimidazole 16, and 6-amino- sion method (Grayer and Harborne, 1994; Irobi et al.,
thiouracil 18 in refluxing acetic acid gave three new 1994) at a concentration 20 mg/mL using DMSO as
ring systems namely pyrazolo[3',4':4,5]pyrimido [1,6- solvent and Tetracycline and Amphotricine as control.
b
][1,2,4]triazolo[3',4':2,1]pyrimido[6,5-
15, pyrazolo[3',4':4,5] pyrimido[1,6-
2':1,2]pyrimido[6,5- ][1,2,4]triazepine 17, and pyrazolo
[3',4':4,5]pyrimido[1,6- ]pyrimido[4',5':2,3]pyrido[4,5-
[1,2,4]triazepine-5(6 )-one 19, respectively (Scheme
4). Condensation of heterocyclic amines 14 16, and 18
with enaminone seems to proceed via nucleophilic
e
b
][1,2,4]triazepine
]benzimidazo[1',
e
b
e]
H
,
5
attack of the amino group to the double bond via a
Michael-type addition, followed by elimination of di-
methylamine then cyclization of the intermediates via
dehydration to give compounds 15, 17, and 19, respec-
tively.
Antitumor screening test
The cytotoxic effects of compound
5 against the
human breast cell line MCF-7, the liver carcinoma cell
line HEPG2-1, and HELA cells were evaluated at the
National Institute of Cancer, Cairo, Egypt. The data
obtained indicated that the IC50 value for this com-
pound against human breast cell line MCF-7 is 4.76
Fig. 1. Effect of concentration of compound
5 on MCF-7 cell
µ
g/mL (Fig. 1) but against the liver carcinoma cell line
HEPG2-1 and HELA cells are 7.19 µg/mL and 8.09 µg/
Fig. 2. Effect of concentration of compound
cell
5 on HEPG2-1
Scheme 4. Reaction of enaminone
amines 14, 16 and 18
5 with heterocyclic

1726
S. M. Riyadh et al.
1. The heterocyclic fused rings system, containing
multicenters for hydrogen accepting properties, are
essential for DNA intercalating activity and anti-
tumor activity.
2. The 1,3,7-triphenyl-6-[(dimethylamino)methylene]-
1
H
-pyrazolo[3',4':4,5]pyrimido[1,6-
5-one ( ) is essential for antitumor activity.
3. The 1,3,7-triphenyl-6-[(dimethylamino)methylene]-
-pyrazolo[3',4':4,5]pyrimido[1,6- ][1,2,4]triazepin-
5-one ( ) and 1,3,8-triphenyl-1 -pyrazolo[3',4':4,5]
pyrimido[1,6- ]isoxazolo[5,4- ][1,2,4]triazepine (12)
b][1,2,4]triazepin-
5
1H
b
5
H
b
e
are essential for antimicrobial activity (in descend-
ing order).
CONCLUSION
In this report, a simple method for the synthesis of
new polyazaheterocyclic ring systems incorporating a
fused [1,2,4]triazepine ring starting from the reaction
Fig. 3. Effect of concentration of compound
5 on HELA cell
of the new enaminone
5 and active methylene com-
pounds, hydrazine hydrate, hydroxylamine, and heter-
ocyclic amines, has been demonstrated. The enaminone
Table I. Antimicrobial activity of the tested compounds*
Inhibition zone diameter (mm/mg sample)
Sample
5
has been evaluated for antitumor activity against
human breast cell line MCF-7 (IC50 = 4.76
liver carcinoma cell line HEPG2-1(IC50 = 7.19
µ
g/mL),
g/mL),
E. coli S. aureus A. flavus C. albicans
no.
(G−)
(G+)
(Fungus) (Fungus)
µ
and HELA cells (IC50 = 8.09
antimicrobial activity of some selected products showed
significant activities against E. coli and S. aureus
µg/mL). In addition, the
3
5
8a
11
12
12
24
12
13
18
12
30
-
11
23
11
12
16
12
30
-
-
-
-
-
-
-
-
18
-
-
-
-
-
-
-
21
.
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