Uses of 1-(3-cyano-4,5,6,7-tetrahydrobenzo[b]-thiophen-2-yl)-3-dodecanoylthiourea as a building block in the synthesis of fused pyrimidine and thiazine systems

Article abstract of DOI:10.1248/cpb.c15-00047

The reaction of lauroyl isothiocyanate and 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile was used to synthesize the title compound 2. Compound 2 could serve as the main building block in the synthesis of many target heterocyclic systems. Various fused pyrimidines were synthesized in the reactions of compound 2 with sodium ethoxide, hydrazine hydrate, phenyl hydrazine, ethyl carbazate, thiourea, and/or 2-aminothiophenol. The structures of the synthesized compounds were confirmed by microanalytical and spectral data.

Full text of DOI:10.1248/cpb.c15-00047

450
Chem. Pharm. Bull. 63, 450–456 (2015)
Vol. 63, No. 6
Regular Article
Uses of 1-(3-Cyano-4,5,6,7-tetrahydrobenzo[b]-thiophen-2-yl)-3-
dodecanoylthiourea as a Building Block in the Synthesis of Fused
Pyrimidine and Thiazine Systems
,a
Magdy Mohamed Hemdan* and Heba Kamal Abd El-Mawgoudeb
a Department of Chemistry, Faculty of Science, Ain Shams University; 11566 Abbasia, Cairo 11566, Egypt: and
b Department of Chemistry, Faculty of Women, Ain Shams University Heliopolis; Cairo 11767, Egypt.
Received January 16, 2015; accepted February 15, 2015
The reaction of lauroyl isothiocyanate and 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile
was used to synthesize the title compound 2. Compound 2 could serve as the main building block in the
synthesis of many target heterocyclic systems. Various fused pyrimidines were synthesized in the reactions
of compound 2 with sodium ethoxide, hydrazine hydrate, phenyl hydrazine, ethyl carbazate, thiourea, and/
or 2-aminothiophenol. The structures of the synthesized compounds were confirmed by microanalytical and
spectral data.
Key words lauroyl isothiocyanate; pyrimidine derivative; fused system; 2-amino-4,5,6,7-tetrahydrobenzo[b]-
thiophene-3-carbonitrile
Pyrimidine and fused heterocyclic pyrimidine derivatives spectrum of compound 2 is presented in Experimental and is
have received significant attention over the past few years in accordance with its proposed structure. The higher δ value
owing to their therapeutic and pharmacological properties.1–6) of NHa proton at δ 14.22ppm, suggests the existence of com-
In general, heterocycles encompassing a pyrimidine moiety pound 2 as its cheleated form shown in Chart 1. Mass spec-
have found applications in a wide spectrum of biological trum of compound 2 revealed correct molecular ion peak at
area.7–9) Such a ring system is often incorporated into drugs M+·, (m/z 419) in addition to some important fragments peaks
designed as anticancer,10,11) antiviral,12) antihypertensive,13) an- consistence with its proposed structure.
algesic,14,15) anti-inflammatory,16) antifungal,17) antibacterial17)
The idea behind the uses of the title compound 2 as a use-
and anti-psoriasis agents.18) Aromatic and heteroaromatic ful building block for synthesis of annulated heterocyclic
compounds bearing an o-aminonitrile group are useful sub- systems depends on the fact that reaction of 2 with different
strates for the synthesis of various condensed pyrimidine nucleophilic reagents (e.g., hydrazines, thiourea, etc.) gives
systems.19–27) In the present investigation we are reporting a intermediates containing nitrile group. The electron deficient
novel building block (the title compound) to give access to carbon of the nitrile site in these intermediates initiated the
the target condensed pyrimidines via intramolecular exo-dig intramolecular exo-dig annulation to provide the target hetero-
annulations.
cyclic compounds.
Treatment of a solution of the adduct 2 in ethanol with
an equivalent amount of freshly prepared sodium ethoxide
Results and Discussion
The title compound 2 is prepared by the reaction of a so- at room temperature afforded tetrahydrobenzothieno[2,3-
lution of lauroyl isothiocyanate 1 in a dry acetonitrile with d]-1,3-diazine derivative 3 (Chart 2). On the other hand
2-amino-4,5,6,7-tetrahydrobenzo[b]-thiophene-3-carbonitrile at refluxing a solution of 2 in ethanol with NaOH (3M) pro-
room temperature (Chart 1). The spectral properties of the duced the amide derivative 4. Furthermore, boiling of com-
new product agree with its proposed structure. Thus its mul- pound 2 in ethanolic hydrochloric acid solution produced
tiple NH groups give rise to bands at 3233 and 3193cm−1 in tetrahydrobenzothieno[2,3-d]-1,3-thiazine derivative 5 in a
its infrared (IR) spectrum. Intense broad band at 1531cm−1, good yield. The infrared spectra of compounds 3–5 showed
indicative of C–N–H vibration is regarded as combination absorption frequencies correlated with NH group, as well as,
bands due to NH-deformation and C–N stretching. It shows C=N group for compounds 3, 5 and in addition to C=O group
1
stretching C–H bands at 2920 and 2849cm−1. Its carbonyl for compounds 4, 5. Their H-NMR spectra displayed the ali-
1
group produced absorption band at 1695cm−1. The H-NMR phatic protons, beside the acidic NH protons in the downfield
Chart 1. Reaction of Lauroyl Isothiocyanate with 2-Amino-4,5,6,7-tetrahydrobenzo[b]-thiophene-3-carbonitrile
*To whom correspondence should be addressed. e-mail: mhemdan39@hotmail.com
© 2015 The Pharmaceutical Society of Japan

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Chem. Pharm. Bull.
451
Chart 2. Reaction of the Title Compound with Sodium Ethoxide, Sodium Hydroxide or Hydrochloric Acid in Ethanol
1
region that was exchangeable with D2O shake. H-NMR spec-
trum of compound 3 in dimethyl sulfoxide (DMSO) solution,
showed its existence in the thiolactim form 3b. The appear-
ance of the two protons of amide group of compound 4 in the
downfield region as two broad singlets is a good evidence for
their magnetic non-equivalence. This suggests the existence of
compound 4 as its chelated form shown in Chart 2. This is in
harmony with the lower frequency of absorption of C=O in its
1
IR spectrum. H-NMR spectrum of compound 5 reveals the
presence of two types NH proton as two broad singlet signals
in the downfield region with equal integration values. This is
a good evidence for its existence as an equilibrium mixture of
the two tautomers 5a and b. The higher δ value of the amino
proton of tautomer 5b (δ 7.29ppm) may be attributable to the
chelation shown in Chart 2 (see Experimental). The formation
of compounds 3 and 5 can be explained on the fact that the ni-
trile site initiated intramolecular exo-diagonal (exo-dig) cycli-
Chart 3. Reaction of the Title Compound with Hydrazine Hydrate,
Phenylhydrazine or Ethyl Carbazate in Ethanol
zation via addition of NHb of compound 2 or sulphur atom of
its thiol form to the nitrile group followed by expulsion of the
lauroyl part in case of compound 3. Base-catalyzed hydrolysis
of compound 2 takes place at its nitrile group and thiouoredo their proposed structures.
part leads to the formation of compound 4.
The formation of compounds 3, 6, 7 can be represented as
The reaction of compound 2 with hydrazine hydrate and/or shown in Chart 4. It is believed that the formation of thiourea
phenylhydrazine led to tricyclic products 6 and 3 respectively, derivative A, is a common intermediate in these reactions,
in excellent yields. On other hand a solution of 2 in ethanol since it is formed as a result of attack of hydrazine hydrate,
with ethyl carbazate in the presence of a catalytic amount of phenylhydrazine or ethyl carbazate to the carbonyl group of
piperidine gave a double annelated product 7 (Chart 3). The compound 2, followed by removal of the lauroyl part in its
microanalytical and spectral data of compounds 6, 7 are pre- hydrazide form. The electron deficient carbon of the nitrile
sented in Experimental and in agreement with their proposed site in the thiourea intermediate A initiated the intramolecular
structures. Their 1H-NMR spectra displayed signals corre- exo-dig annulation to provide 3 in case of phenylhydrazine or
sponding to aliphatic protons as well as acidic NH and OH adds another mole of hydrazine or ethyl carbazate to give the
protons in the downfield region that was exchangeable with other key intermediates which initiated intramolecular exo-dig
D2O. Moreover, their mass spectra showed the correct molecu- annulation to provide targets compounds 6 and 7, respectively.
lar ion peaks and important fragment peaks in agreement with
Refluxing a solution of compound 2 in ethanol with thio-

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Chem. Pharm. Bull.
Vol. 63, No. 6 (2015)
Chart 4. The Proposed Mechanisms of Formation of the Target Products of Reaction of the Title Compound with Hydrazine Hydrate, Phenylhydra-
zine or Ethyl Carbazate
urea in the presence of a catalytic amount of sodium hydrox- 8 as shown in Chart 6. The formation of compound 9 can be
ide afforded fused tetracyclic compound 8. On the other hand, explained as depicted in Chart 7.
the reaction of compound 2 with 2-aminothiophenol in the
Biological Activity The antimicrobial screening of some
presence of a catalytic amount of piperidine gave a fused pen- of the synthesized compounds was done using the hole dif-
tacyclic derivative 9 (Chart 5). The appearance of the amino fusion method. The possible antimicrobial activities of com-
proton (NH) of compound 8 as two broad singlets suggests pounds 2, 3, 5, 7–9 were investigated to six standard organ-
its existence in DMSO solution as an equilibrium mixture of isms including the Gram-positive bacteria, Bacillus subtilis
tautomers 8a and b in ratio of 3:1. The product of the reaction and Staphylococcus aureus and the Gram-negative bacteria,
of compound 2 with 2-aminothiophenol may have one of the Escherichia (E.) coli and Pseudomonas, in addition to unicel-
two possible structures 9 or 10. Structure 9 is more accept- lular fungi yeast and multicellular fungi Aspergillus flavus.
1
able one on the basis of its H-NMR spectrum that displayed The obtained results are presented in Table 1. Standard solu-
two singlet signals equivalent to one proton in the downfield tions of Septrin D.S. (antibacterial agent) and Fungistatin (an-
region corresponding to NH and SH proton in the ratio 10:1.
tifungal agent) were served as positive controls.
The formation of compound 8 can be explained on the basis
Data in Table 1 emphasized the fact that the chemical agent
of cyclocondensation of thiourea with compound 2 to give in- symbolized 2 is exhibited low activity only against yeast (the
termediate in which the nitrile site initiated the intramolecular unicellular fungi), compound 3 revealed low activity only
exo-dig annulations to provide the target heterocyclic system against Bacillus subtilis (Gram-positive bacteria) and the

Vol. 63, No. 6 (2015)
Chem. Pharm. Bull.
453
Chart 5. Reaction of the Title Compound with Thiourea, and 2-Aminothiophenol in Ethanol
Chart 6. The Proposed Mechanism of Formation of the Target Product of Reaction of the Title Compound with Thiourea
Chart 7. The Proposed Mechanism of Formation of the Target Product of Reaction of the Title Compound with 2-Aminothiophenol
chemical agent 9 showed low activity against both Staphy- other microorganisms. The other compounds 5, 7 and 8 didnʼt
lococcus aureus (Gram-positive bacteria) and Pseudomonas show activity at all against the examined microorganisms.
(Gram-negaitive bacteria) and didnʼt show activity against the

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Chem. Pharm. Bull.
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Table 1. Antimicrobial Activity of Selected Compounds
Inhibition zone diameter (cm/gm sample)
No.
Yeast
(unicellular fungi)
Aspergillus flavus
(multicellular fungi)
Bacillus subtilis G+ Staphylococcus aureus G+
E. coli G−
Pseudomonas G−
2
3
5
7
8
9
S
F
—
5
—
—
—
—
—
5
—
—
—
—
—
—
40
—
—
—
—
—
5
5
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
25
30
25
20
15
S=Septrin D.S. (antibacterial agent), F=Fungistatin (antifungal agent). The concentration of all synthesized compounds and the reference was (5mg/1mL of DMSO). Zone
of inhibition: <15mm (low); 15–24mm (moderate); 25–34mm (high); 35–44mm (very high); —: no inhibition.
(2Hd, CH2, m), 2.70 (2Hc, CH2, m), 4.31 (1H, SH, exchange-
Experimental
Melting points of the reaction products were determined in able, brs), 6.99 (2H, NH2, exchangeable, brs); IR (KBr) ν:
open capillary tubes on an electrothermal melting point ap- 3444, 3340, 3194 (NH), 2933, 2854 (C–Halkyl), 1597 (C=N),
paratus and were uncorrected. The elemental analyses were 1554 (C=C), 1235 (C=S); MS (70eV) m/z (%): 237 (M+·, 57),
performed on a Perkin-Elemer 2400 CHN elemental analyzer. 219 (16), 204 (17), 179 (39), 150 (30), 121 (18), 71 (56), 57
The infrared spectra were recorded on Perkin-Elemer Modle (100). Anal. Calcd for C10H11N3S2 (237.34): C, 50.60; H, 4.67;
297 Infrared spectrometer using the KBr wafer technique. The N, 17.70. Found C, 50.44; H, 4.65; N, 17.46%.
1H-NMR spectra were measured on Varian Gemini 300MHz
2-Amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbox-
spectrometer, with chemical shift (δ) expressed in ppm down- amide (4) A solution of compound 2 (3mmol) and (3M)
field with tetramethylsilane (TMS) as internal standard, in sodium hydroxide (5mL) in 30mL ethanol was refluxed for
DMSO-d6. Mass spectra were determined on Shimadzu GC- 2h. Vacuum-distilled to ca. half-volume and acidified with
MSQP 1000 EX instrument operating at 70eV. Thin layer 3M hydrochloric acid. The precipitate was collected and
chromatography (TLC) was run using TLC aluminum sheets recrystallized from ethanol to give compound 4 as pale yel-
1
silica gel F254 (Merck). It was carried out the monitoring of the low crystals; yield 73%; mp>300°C; H-NMR (DMSO-d6) δ:
progress of all reactions and homogeneity of the synthesized 1.77 (4He, 2CH2, m), 2.64 (2Hd, CH2, m), 2.76 (2Hc, CH2, m),
compounds.
7.19 (2H, NH2, exchangeable, brs), 11.94, 13.03 (2H, CONH2,
1-(3-Cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl)- exchangeable, two brs); IR (KBr) ν: 3440, 3358 (NH2), 3220,
3-dodecanoylthiourea (2) A solution of lauroyl isothio- 3176 (NH), 2933, 2840 (C–Halkyl), 1632 (C=O), 1553 (C=C);
cyanate (3mmol) and 2-amino-4,5,6,7-tetrahydrobenzo[b]- MS (70eV) m/z (%): 196 (M+·, 4), 185 (6), 179 (50), 178
thiophene-3-carbonitrile (3mmol) in 30mL dry acetonitrile (67), 163 (16), 150 (100), 134 (25), 116 (19). Anal. Calcd for
was stirred at room temperature for 2h. The resulting C9H12N2OS (196.27): C, 55.08; H, 6.16; N, 14.27. Found C,
yellow solid product was collected by filtration and re- 54.87; H, 5.81; N, 13.96%.
crystallized from ethanol to give 2 as pale yellow crys-
N-(4-Imino-5,6,7,8-tetrahydrobenzothieno[2,3-d][3,1]thiazin-
tals. Yield 86%; mp 132–134°C; 1H-NMR (DMSO-d6) δ: 2-yl)dodecanamide (5) A solution of 2 (3mmol) in 30mL
0.84 (3H, CH3(CH2)8CH2CH2CO, t, J=6.6Hz), 1.24 (16H, ethanol and 3M hydrochloric acid (5mL) was refluxed for
CH3(CH2)8CH2CH2CO, m), 1.56 (2H, CH3(CH2)8CH2CH2CO, 3h. The solution was vacuum-evaporated to small volume.
m), 1.76 (4He, 2CH2, m), 2.44 (2H, CH3(CH2)8CH2CH2CO, t, A solution of sodium carbonate (0.1N) was added until effer-
J=7.5Hz), 2.54 (2Hd, CH2, m), 2.62 (2Hc, CH2, m), 11.97 (1H, vescence ceased. The yellow precipitate was filtered off and
NHb, exchangeable, brs), 14.22 (1H, NHa, exchangeable, brs); recrystallized from ethanol to give compound 5 as pale yel-
1
IR (KBr) ν: 3233, 3193 (NH), 2920, 2849 (C–Halkyl), 2211 low crystals; yield 81%; mp 196–198°C; H-NMR (DMSO-d6)
(CN), 1695 (C=Oamide), 1588 (C=C), 1200 (C=S); MS (70eV) δ: 0.85 (3H, CH3(CH2)8CH2CH2CO, t, J=6.6Hz), 1.30 (16H,
m/z (%): 419 (M+·, 30), 360 (3), 237 (27), 220 (100), 204 (3), CH3(CH2)8CH2CH2CO, m), 1.54 (2H, CH3(CH2)8CH2CH2CO,
192 (72), 178 (88), 160 (4), 150 (22), 134 (7), 59 (37). Anal. m), 1.73 (4He, 2CH2, m), 2.40 (2H, CH3(CH2)8CH2CH2CO, m),
Calcd for C22H33N3OS2 (419.65): C, 62.97; H, 7.93; N, 10.01. 2.68 (4H, 2CH2, m), 11.38 (1H, NH=, exchangeable, brs), for
Found C, 62.82; H, 7.87; N, 9.79%.
5a: 14.08 (1H, NHCO, exchangeable, brs), for 5b: 7.29 (1H,
Uses of Compound 2 in Synthesis Different Target Hetero- NH, thiazine, exchangeable, brs); IR (KBr) ν: 3411, 3322, 3195
cyclic Systems 4-Amino-5,6,7,8-tetrahydrobenzothieno[2,3- (NH), 2920, 2850 (C–Halkyl), 1704 (C=O), 1633, 1592 (C=N),
d]-1,3-diazine-2-thione (3) A mixture of 2 (3mmol) and 1559, 1531 (C=C MS (70eV) m/z (%): 419 (M+·, 3), 403 (25),
sodium ethoxide (3mmol) in 30mL absolute ethanol was 368 (1), 263 (2), 221 (100), 193 (29), 178 (8), 150 (3). Anal.
stirred at room temperature for 4h. A yellow solid product Calcd for C22H33N3OS2 (419.65): C, 62.97; H, 7.93; N, 10.01.
was obtained, filtered off, and recrystallized from ethanol Found C, 63.14; H, 7.72; N, 9.68%.
to give compound 3 yellow crystals. The same product was
Reaction of Compound 2 with the Nitrogen Nucleophiles
obtained on refluxing of a solution of 2 (3mmol) in ethanol General Procedure To a solution of compound 2 (3mmol)
(30mL) and phenylhydrazine (3mmol) for 4h. Yield 79%; in ethanol (30mL), hydrazine hydrate (3mmol) was added.
1
mp>300°C; H-NMR (DMSO-d6) δ: 1.78 (4He, 2CH2, m), 2.60 The reaction mixture was refluxed for 4h, then, cooled to

Vol. 63, No. 6 (2015)
Chem. Pharm. Bull.
455
room temperature. A solid was obtained that was filtered off Hole Diffusion Method Dissolve the samples in DMSO
and recrystallized from ethanol to give compound 6. The (5mg/1mL). Make bacterial suspension and fungal suspen-
same procedure was done with ethyl carbazate, thiourea and/ sion in Nutrant broth media for bacteria and Sabarude broth
or o-aminothiophenol. A catalytic amount of piperidine was media for Fungi. Take 1mL of bacterial or fungal suspension
added in case of reaction with ethyl carbazate and o-amino- in sterallized petri dishes and pour media on it and mix well
thiophenol while, a catalytic amount of sodium hydroxide was to homogenized inoculums with media. After media solidified,
added in case the reaction of 2 with thiourea. The progress of make holes in media with courk pourer. Add 50µg of samples
all reactions and homogeneity of the synthesized compounds solution and control solution in holes. Incubate plates at 37°C
were monitored by TLC. The solid obtained for each case was for 24h. Investigate plate after incubation period by measure
recrystalized from a suitable solvent to give the corresponding diameter of inhibition zone and get courk pourer diameter.
compound.
Actually inhibition zone=D. of inhibition zone−D. of courk
3-Amino-4-imino-2-thioxo-5,6,7,8-tetrahydrobenzo- pourer.
thieno[2,3-d]-1,3-diazine (6) Pale yellow crystals; yield 85%;
mp 271–273°C (EtOH); 1H-NMR (DMSO-d6) δ: 1.77 (4He,
2CH2, m), 2.63 (2Hd, CH2, m), 2.76 (2Hc, CH2, m), 7.93 (2H, interest.
NH2, exchangeable, brs), 8.35 (1H, NH, exchangeable, brs),
Conflict of Interest The authors declare no conflict of
10.22 (1H, NH=, exchangeable, brs); IR (KBr) ν: 3428, 3310,
3250, 3120 (NH), 2925, 2829 (C–Halkyl), 1630 (C=N), 1573,
1533 (C=C), 1186 (C=S); MS (70eV) m/z (%): 252 (M+·, 9),
237 (100), 221 (12), 204 (10), 192 (5), 179 (34), 160 (7), 134
(6), 118 (8). Anal. Calcd for C10H12N4S2 (252.36): C, 47.59; H,
4.79; N, 22.20. Found C, 47.43; H, 4.46; N, 21.87%.
References
1) Figueiredo J. A., Ismael M. I., Pinheiro J. M., Silva A. M., Justino
J., Silva F. V. M., Goulart M., Mira D., Araújo M. E. M., Campoy
R., Rauter A. P., Carbohydr. Res., 347, 47–54 (2012).
2) Doláková P., Dračínský M., Masojídková M., Šolínová V., Kašička
V., Holý A., Eur. J. Med. Chem., 44, 2408–2424 (2009).
3) Soliman R., Habib N. S., Ismail K., Moustafa A., Sarg M. T., Fanaki
N. H., Boll. Chim. Farm., 142, 167–174 (2003).
2-Hydroxy-8,9,10,11-tetrahydrobenzothieno[2′,3′:4,5]pyrimido
-
[3,4-b]-1,2,4-triazole-5(6H)-thione (7) Pale brown crystals;
4) Rashad A. E., Ali M. A., Nucleosides Nucleotides Nucleic Acids,
25, 17–28 (2006).
1
yield 79%; mp>300°C (EtOH); H-NMR (DMSO-d6) δ: 1.78
(4He, 2CH2, m), 2.69 (2Hd, CH2, m), 2.85 (2Hc, CH2, m),
7.02 (2H, NH and OH, exchangeable, brs); IR (KBr) ν: 3448
(OH), 3306, 3208 (NH), 2924, 2839 (C–Halkyl), 1625 (C=N),
1547 (C=C), 1229 (C=S); MS (70eV) m/z (%): 278 (M+·, 38),
272 (43), 261 (40), 248 (36), 231 (45), 218 (48), 194 (45), 141
(12), 129 (34), 69 (100). Anal. Calcd for C11H10N4OS2 (278.35):
C, 47.46; H, 3.62; N, 20.13. Found C, 47.18; H, 3.71; N,
19.76%.
6-Imino-4-undecyl-6,12-dihydro-2H-7,8,9,10-tetrahydro-
benzothieno[2′,3′ : 4,5]pyrimido[1,2-a][1,3,5]triazine-2-thione
(8) Colorless crystals; yield 81%; mp 251–253°C (EtOH);
1H-NMR (DMSO-d6) δ: 0.85 (3H, CH3(CH2)8CH2CH2CO, t,
J=6.9Hz), 1.24 (16H, CH3(CH2)8CH2CH2CO, m), 1.47 (2H,
CH3(CH2)8CH2CH2CO, m), 1.81 (4He, 2CH2, m), 2.17 (2H,
CH3(CH2)8CH2CH2CO, t, J=7.5Hz), 2.79 (2Hd, CH2, m), 2.91
(2Hc, CH2, m), 7.47 (1H, NH=, exchangeable, brs), for 8a:
6.80 (1H, NH, exchangeable, brs), for 8b: 6.94 (1H, NH, ex-
changeable, brs); IR (KBr) ν: 3442, 3294, 3113 (NH), 2934,
2856 (C–Halkyl), 1648 (C=N), 1565 (C=C), 1272 (C=S); MS
(70eV) m/z (%): 443 (M+·, 80), 417 (65), 381 (50), 368 (81), 331
(72), 313 (88), 260 (48), 224 (98), 205 (94), 155 (94), 106 (100),
81 (91). Anal. Calcd for C23H33N5S2 (443.67): C, 62.26; H, 7.50;
N, 15.78. Found C, 61.89; H, 7.22; N, 15.64%.
5) Litvinov V. P., Russ. Chem. Bull., 53, 487–516 (2004).
6) Padmaja A., Payani T., Reddy G. D., Padmavathi V., Eur. J. Med.
Chem., 44, 4557–4566 (2009).
7) Wnuk S. F., Lewandowska E., Companioni D. R., Garcia P. I. Jr.,
Secrist J. A. III, Org. Biomol. Chem., 2, 120–126 (2004).
8) Cushman M., Sambaiah T., Jin G., Illarionov B., Fischer M., Bacher
A., J. Org. Chem., 69, 601–612 (2004).
9) Sondhi S. M., Johar M., Rajvanshi S., Dastidar S. G., Shukla R.,
Raghubir R., Lown J. W., Aust. J. Chem., 54, 69 (2001).
10) El-Gaby M. S. A., Abdel-Hamide S. G., Ghorab M. M., El-Sayed S.
M., Acta Pharm., 49, 149 (1999).
11) de Vries E. G. E., Gietema J. A., Workman P., Scott J. E., Craw-
shaw A., Dobbs H. J., Dennis I., Mulder N. H., Sleijfer D. T. H.,
Willemse P. H., Br. J. Cancer, 68, 641–644 (1993).
12) Nasr M. N., Gineinah M. M., Arch. Pharm., 335, 289 (2002).
13) Alam O., Khan S., Siddiqui N., Ahsan W., Verma S., Gilani S., Eur.
J. Med. Chem., 45, 5113–5119 (2010).
14) Gupta J. K., Sharma P. K., Dudhe R., Chaudhary A., Singh A.,
Verma P. K., Mondal S. C., Yadav R. K., Kashyap S., Med. Chem.
Res., 21, 1625–1632 (2012).
15) Hassan N. A., Molecules, 5, 826–834 (2000).
16) Vega S., Alonso J., Diaz A., Junquera F., J. Heterocycl. Chem., 27,
269–273 (1990).
17) Srivastava A. N., Singh N. P., Shriwastaw C. K., J. Serb. Chem.
Soc, 78, 1 (2013).
18) Kuyper L. F., Baccanari D. P., Jones M. L., Hunter R. N., Tansik R.
L., Joyner S. S., Boytos C. M., Rudolph S. K., Knick V., Wilson R.
H., Caddell J. M., Friedman H. S., Comley J. C. W., Stables J. N., J.
Med. Chem., 39, 892–903 (1996).
19) Ellis G. P., “The Chemistry of Heterocyclic Compounds,” Vol. 47,
ed. by Taylor E. C., John Wiley and Sons, New York, 1987, p. 226.
20) Sauter F., Fröhlich J., Shaifullah Chowdhury A. Z. M., Sci. Pharm.,
64, 647–653 (1996).
21) Sauter F., Fröhlich J., Blasl K., Gewald K., Heterocycles, 40, 851–
866 (1995).
22) Sauter F., Fröhlich J., Shaifullah Chowdhury A. Z. M., Hametner
C., “Poster Presented at Electronic Conference on Heterocyclic
Chemistry (ECHET 96),” ed. by Rzepa H. S., Synder J. (CD-ROM),
Royal Society of Chemistry Publications, 1996.
10,11,12,13-Tetrahydrobenzothieno[2′,3′ : 4,5]pyrimido[3,4-
a]-benzimidazol-7(8H)-thione (9) Brown crystals; yield 68%;
mp>300°C (EtOH); H-NMR (DMSO-d6) δ: 1.78 (4He, 2CH2,
1
m), 2.69 (2Hd, CH2, m), 2.85 (2Hc, CH2, m), 6.10 (1H, SH,
exchangeable, brs), 6.46 (1H, Ar-H, t), 6.66 (1H, d, J=8.1Hz),
7.01 (1H, NH, exchangeable, brs), 7.07 (1H, Ar-H, t), 7.41 (1H,
d, J=7.5Hz); IR (KBr) ν: 3444, 3342, 3192 (NH), 2933, 2855
(C–Halkyl), 1597 (C=N), 1545 (C=C), 1233 (C=S); MS (70eV)
m/z (%): 311 (M+·, 34), 287 (21), 243 (30), 208 (23), 180 (26),
151 (31), 119 (3), 77 (9), 66 (100). Anal. Calcd for C16H13N3S2
(311.42): C, 61.71; H, 4.21; N, 13.49. Found C, 61.60; H, 4.14;
N, 13.21%.
Measurement of Antimicrobial Activity Using the

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Vol. 63, No. 6 (2015)
23) Shaifullah Chowdhury A. Z. M., J. Bangladesh Acad. Sci., 23,
59–67 (1999).
24) Papadopoulos E. P., J. Heterocycl. Chem., 18, 515–518 (1981).
25) Shaifullah Chowdhury A. Z. M., Shibata Y., Chem. Pharm. Bull.,
49, 391–395 (2001).
26) Bhuiyan M. M. H., Rahman K. M. M., Hossain M. K., Rahim M.
A., Hossain M. I., Croat. Chem. Acta, 78, 633–636 (2005).
27) El-Sharkawy K. A., El-Sehrawi H. M., Ibrahim R. A., Inter. J. Org.
Chem., 2, 126–134 (2012).