Scholarly article on topic 'Synthesis and antitumor evaluation of thiophene based azo dyes incorporating pyrazolone moiety'

Synthesis and antitumor evaluation of thiophene based azo dyes incorporating pyrazolone moiety Academic research paper on "Chemical sciences"

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{Thiophene / Pyrazoles / "Azo dyes" / "Color measurements" / "Fastness properties" / "Antitumor evaluation"}

Abstract of research paper on Chemical sciences, author of scientific article — Moustafa A. Gouda, Hadeer Fakhr Eldien, Margret M. Girges, Moged A. Berghot

Abstract A series of thiophene incorporating pyrazolone moieties 5a–f and 6a–c were synthesized via diazo coupling of diazonium salt of 3-substituted-2-amino-4,5,6,7-tetrahydrobenzo[b]thiophenes 1a–c with 3-methyl-1H-pyrazol-5(4H)-one, 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one or 3-amino-1H-pyrazol-5(4H)-one, respectively. Newly synthesized dyes were applied to polyester fabric as disperse dyes in which their color measurements and fastness properties were evaluated. These dyes showed generally red to blue shifted color with high extinction coefficient in comparison with aniline-based azo dyes. The antitumor activity of the synthesized dyes was evaluated. The results showed clearly that most of them exhibited good activity and compounds 5c and 5d exhibited moderate activity.

Academic research paper on topic "Synthesis and antitumor evaluation of thiophene based azo dyes incorporating pyrazolone moiety"

Journal of Saudi Chemical Society (2012) xxx, xxx-xxx

ORIGINAL ARTICLE

Synthesis and antitumor evaluation of thiophene based azo dyes incorporating pyrazolone moiety

Moustafa A. Gouda *, Hadeer Fakhr Eldien, Margret M. Girges, Moged A. Berghot

Chemistry Department, Faculty of Science, Mansoura University, 35516 Mansoura, Egypt Received 16 April 2012; accepted 23 June 2012

KEYWORDS

Thiophene; Pyrazoles; Azo dyes;

Color measurements; Fastness properties; Antitumor evaluation

Abstract A series of thiophene incorporating pyrazolone moieties 5a-f and 6a-c were synthesized via diazo coupling of diazonium salt of 3-substituted-2-amino-4,5,6,7-tetrahydrobenzo[b]thiophenes 1a-c with 3-methyl-1H-pyrazol-5(4H)-one, 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one or 3-amino-1H-pyrazol-5(4H)-one, respectively. Newly synthesized dyes were applied to polyester fabric as disperse dyes in which their color measurements and fastness properties were evaluated. These dyes showed generally red to blue shifted color with high extinction coefficient in comparison with aniline-based azo dyes. The antitumor activity of the synthesized dyes was evaluated. The results showed clearly that most of them exhibited good activity and compounds 5c and 5d exhibited moderate activity.

© 2012 King Saud University. Production and hosting by Elsevier B.V. All rights reserved.

1. Introduction

It has been known for many years that the azo compounds are the most widely used class of dyes due to their versatile application in various fields such as the dyeing of textile fibers, the coloring of different materials, in biological-medical studies and advanced applications in organic synthesis (Waring & Halas, 1990; Zollinger, 2003; Bhatti and Seshadri, 2004; Tanaka et al., 1984; Towns, 1999; Dickey et al., 1959). In

Corresponding author. Current Address: Department of Chemistry, Faculty of Science and Arts, Ulla, Taibah University, Saudi Arabia. Tel.: +20 50 6432235; fax: +20 502246781.

E-mail address: dr_mostafa_chem@yahoo.com (M.A. Gouda). Peer review under responsibility of King Saud University.

recent years, the use of heterocyclic intermediates in the synthesis of azo disperse dyes is well established, and the resultant dyes exhibit good tinctorial strength and brighter dyeing than those aniline-based components (Penchev et al., 1991; Peters and Gbadamosi, 1992; Kraska and Sokoowska-Gajda, 1987; Sokolowska-Gajda, 1991, 1992). Furthermore, 2-amino-thiophene and its benzo analogs are very useful compounds as intermediates in the dyestuff industry and find a wide range of pharmaceutical applications (Lutjens et al., 2003; Nikolakopoulos et al., 2006; Pillai et al., 2005). Thiophene based azo dyes showed generally red to blue color with a high extinction coefficient in comparison with aniline-based azo dyes. On the other hand, pyrazole nucleus has pronounced pharmacological applications as anti-anxiety, antipyretic (Yamaguchi and Ishikawa, 1981), analgesic and anti-inflammatory drugs (Georgiadou and Tsatsaroni, 2002; Yen and Wang, 2004). To our knowledge 2-aminothiophene derivatives incorporated pyrazole moiety are little known in the literature (Abu-Hashem et al., 2010; El Bialy and Gouda, 2011; Gouda et al., 2010).

1319-6103 © 2012 King Saud University. Production and hosting by Elsevier B.V. All rights reserved. http://dx.doi.Org/10.1016/j.jscs.2012.06.004

Therefore, our aim in this work is to synthesize some new pyrazole derivatives incorporating thiophene moiety, starting from 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene derivatives in order to evaluate their dyeing behavior as dyestuff on polyester fabric and their biological activity as antitumor agents.

2. Results and discussion

2.1. Chemistry

The synthetic routes adopted to obtain the target compounds are described in Scheme 1. 3-Substituted-2-amino-4,5,6,7-tet-rahydrobenzo[b]thiophene derivatives 1a-c were prepared via multicomponent condensation of cylohexanone with ethyl cya-noacetate, malononitrile or cyanoacetamide and elemental sulfur containing morpholine as a catalyst following a procedure described by Gewald (1965).

Treatment of 1a-c in HCl with sodium nitrite solution afforded the corresponding diazonium salts which coupled with pyrazoles 3a or 3b or 4 in pyridine or ethanol containing sodium acetate to afford the corresponding hydrazones 5a-f and 6a-c, respectively. Assignment of the newly synthesized

compounds was based on elemental analyses and spectral data (IR, 1H NMR and mass spectra) (cf. Section 4).

2.2. Dyeing of polyester fabrics and dyeing properties

2.2.1. Color measurement

The effect of the nature of different substituents on dyeing behavior, color hue and depth was discussed. This investigation depends on some spectral data of the dyed materials. The most commonly used function f(R) is the one developed theoretically by Kubelka and Munk. In their theory, the optical properties of a sample are described by two values "K" is the measure of the light absorption and "S" is the measure of the light scattering. On textiles, "K" is determined primarily by the dyestuffs and "S" only by the substrate. From the wave-length Kubelka and Munk calculate the following relationship for reflectance R of thick, opaque samples with the constant of "K" and "S":

K/S =(1 - R)2/2R (1)

In this equation R is used as a ratio, e.g. 32% reflectance as 0.32. The K/S value at kmax was taken as a measure of color depth.

N2+Cl-

pyridine

X 5a-f

5a, R=H, X= COOEt 5b, R=H,X=CONH2 5c, R=H,X= CN 5d, R= Ph, X= COOEt 5e, R=Ph,X= CONH2 5f, R= Ph, X= CN

6a-c o

6a, X= COOEt 6b, X= CONH, 6c, X= CN

R 3a, b

pyridine

NaNO2/HCl

N,+Cl-

pyridine

Scheme 1 Synthesis of substituted-4-{2-[(or 3-phenyl-)4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl]hydrazono}-1H-pyrazol-5(4H)-one derivatives 5 and 6.

On the other hand, the psychometric coordinates (L*, a*, b ) for each dyed sample were obtained to illustrate the color hues, where "L '': the lightness ranging from 0 to 100 (0 for black and 100 for white). ''a '': the red-green axis, ( + ) for red, zero for grey and (—) for green. ''b '': the yellow-blue axis, ( + ) for yellow, zero for grey and (—) for blue.

The dyestuff (4Z)-4-(2-phenylhydrazono)-3-methyl-1 H-pyrazol-5(4H)-one (A) is taken as the standard in color difference calculation (AL*, DC*, AH*, and DE) (Fadda etal., 1990, 1995a,b). The results are measured using CIE-LAB techniques and given in Table 1, where DL*: lightness difference, DC*: chroma difference, DH*: hue difference and DE: total color difference. The negative sign of AL indicates that the dyed fiber becomes darker than the standard but, a positive sign indicates that the dyed fiber becomes lighter than the standard. The negative sign of AC indicates that the dyed fiber becomes duller than the standard but, a positive sign indicates that the dyed fiber becomes brighter than the standard. The negative sign of AH indicates that the color directed to red color while, a positive sign indicates that the color directed to yellow.

The values of K/S of A, 5a-f and 6a-c vary from 0.39 to 13.68. The introduction of pyrazolone ring systems in dyes 5a-f and 6a-c increases the strength of K/S value and deepens the color compared with the parent dye A (Table 1).

The replacement of the (COOEt) by (CONH2) or (CN) group into thiophene ring system increases the value of K/S, indicating that the dyes 5b, 5c, 5e, 5f, 6b and 6c showed higher affinity toward dyeing of polyester fabrics than 5a, 5d and 6a, respectively. Dyes 5a-f and 6a-c with — ve AC and — ve AL values are duller and darker than the parent dye A. The negative sign of AH in 5a-f and 6a-c indicates that the color directed to red color. The positive value of a* and b* indicates that all groups shift the color hues of the dye to the reddish direction on the red-green axis and to the yellowish direction in the yellow-blue axis, respectively.

2.2.2. Assessment of color fastness

Most influences that can affect fastness are light, washing, heat and perspiration, and atmospheric pollution. Conditions of such tests are chosen to correspond closely to treatments employed in manufacture and of ordinary use conditions (Society of Dyes and Colourists, 1990). Results are given after usual matching of tested samples against standard reference (the grey scale) (Society of Dyes and Colourists, 1990). The results revealed that these dyes have good fastness properties (Table 2).

2.3. Antitumor activity

2.3.1. Effect of drugs on the viability of Ehrlich ascites carcinoma cells (EAC) in vitro

Nine pyrazole derivatives were tested for cytotoxicity against the well known established model EAC in vitro (Karrer and Rtjbini, 1965). Results for the ED100, ED50 and ED25 values of the active compounds are summarized in Table 3. The data showed clearly that compounds 6a-c are more potent than 5-fluorouracil and compounds 5b, 5e and 5f exhibited good activities and compounds 5c and 5d exhibited moderate activity compared with 5-fluorouracil. From the structure-activity relationships (SARs) by comparing the results obtained of antitumor activities of the compounds reported in this study to their structures and to the recently reported results (Gouda and Abu-Hashem, 2011) it would appear that (i) Introducing a hydrazopyrazol-5-one ring in position 2 to benzothiophene is necessary for the cytotoxic activity. (ii) The pyrazoles 6a-c exhibited high cytotoxic activity which may be due to the presence of amino group in position 3 of the pyrazol-5-one moiety (Fig. 1). Also, the order of antitumor activity of this series of compounds follows 6c < 6b < 6a, this may be due to replacement of CONH2 by CN or COOEt groups in position 3 of ben-zothiophene ring. (iii) The reactivity of 5c < 5b < 5a may be due to the presence of the COOEt group at position 3 to the thiophene moiety. (iv) Transformation of the COOEt or CN group into the CONH2 group at position 3 of the thiophene ring system in compounds 5d-f increases the antitumor activity.

3. Conclusion

Nine useful disperse dyes 5a-f and 6a-c were synthesized by the diazo coupling reaction and their dyeing characteristics on polyester were investigated. Also these dyes showed generally red to blue shift color with high extinction coefficient in comparison with aniline-based azo dye (A) and showed good light, washing, heat and acid perspiration fastness with antibacterial activities. The remarkable degree of brightness after washings is an indication of good penetration and the excellent affinity of these dyes for the fabric due to the accumulation of polar groups. On the other hand, the synthesized dyes were evaluated as antitumor agents. The biological data showed that most of the investigated compounds exhibited good activities and compounds 5c and 5d exhibited moderate activities compared with 5-fluorouracil as a well known cytotoxic agent.

Table 1 Optical measurements of compounds 5a-f and 6a-c.

Dye R% a b* L* C* H* AL AC AH AE K/S

A 2.37 0.71 86.25 76.36 86.25 89.53 - - - - 20.1

5a 7.76 38.42 32.55 45.93 50.36 40.27 -30.43 -35.89 -49.26 68.12 5.48

5b 23.21 6.8 12.55 69.78 14.28 61.56 -6.58 -71.97 -27.97 77.49 1.27

5c 12.32 2.28 14.06 55.17 14.25 80.78 -21.19 -72 -8.75 75.56 3.12

5d 9.44 35.62 35.93 51.14 50.59 45.24 -25.22 -35.66 -44.29 62.2 4.34

5e 29.33 17.06 16.1 69.39 23.46 43.35 -6.97 -62.79 -46.18 -78.25 0.85

5f 19.36 17.73 29.54 67.94 34.46 59.03 -8.42 -51.79 -30.5 60.69 1.68

6a 12.28 22.32 25.01 58.39 33.52 48.26 -17.97 -52.73 -41.27 69.33 3.13

6b 13.67 13.28 13.84 54.71 19.18 46.2 -21.65 -67.07 -43.33 82.73 2.72

6c 18.8 9.49 8.23 58.23 12.56 40.95 -18.13 -73.69 -48.58 90.25 1.75

Table 2 Fastness properties of compounds 5a-f and 6a-c.

Dye Washing, 75 oc Rubbing Sublimation Acid perspiration Light, 4 h

Dry Wet 180 OC 210 oc

A 4 4-5 4-5 3 3 4 8

5a 4-5 3 2 4-5 4-5 4-5 6

5b 4-5 5 5 4-5 4-5 4-5 6

5c 4-5 5 5 4-5 4-5 4-5 8

5d 4-5 3 3 4-5 4-5 4-5 6

5e 4-5 3 3 4-5 4-5 4-5 6

5f 4-5 3 3 4-5 4-5 4-5 6

6a 4-5 4 4 4-5 4-5 4-5 8

6b 4-5 4 4 4-5 4-5 4-5 8

6c 4-5 5 5 3-4 3-4 4-5 6

Table 3 In vitro cytotoxicity of tested compounds (Ehrlich ascites cells dead %).

Compound No. % Dead

100 ig/mL 500 ig/mL 25 ig/mL

5-Fu 97.3% 68% 38.6%

5a 79.4% 71% 43%

5b 96.5% 66.6% 38.1%

5c 84% 53.3% 29.8%

5d 70% 39.1% 22.8%

5e 97.1% 69.3% 40.2%

5f 96% 65% 36.7%

6a 100% 98.6% 94%

6b 98.4% 81% 65%

6c 98.1% 79% 60%

The dead % refers to the % of the dead tumor cells and 5-FU is 5-fluorouracil, a well known cytotoxic agent.

were found to agree favorably with the calculated values and were carried out at the Microanalytical Center at Cairo University, Giza, Egypt. The dyeing assessment, fastness tests, color measurements were carried out in El-Nasr Company for Spinning and Weaving El-Mahalla El-Kubra, Egypt.

4.2. General procedure for the synthesis of 5a-c

A well stirred solution of 2-aminothiophenes 1a-c (0.005 mol) in 3.6 mL of conc. HCl and 1 mL of H2O was cooled in an ice-bath and diazotized with the solution of 0.345 g NaNO2 (0.005 mol) in 2 mL H2O. The cold diazonium solution was added slowly to a well stirred solution of 3-methyl-1H-pyra-zol-5(4H)-one (3a) (0.49 g, 0.005 mol) in pyridine (30 mL). The reaction mixture was stirred for another 2 h. The crude product was filtered off, dried well and recrystallized from the suitable solvent to give 5a-c.

pyrazole

X= COOEt, CN, CONH2

Figure 1 Structure-activity relationships (SARs) of the more potent moieties.

4. Experimental

4.1. Instruments

4.2.1. (E)-Ethyl 2-(2-(3-methyl-5-oxo-1H-pyrazol-4(5H)-ylidene)hydrazinyl)-4,5,6,7-tetra-hydrobenzo[b]thiophene-3-carboxylate (5a)

Reddish brown powder; Yield: 60%; mp: 154 0C; IR (KBr, v cm-1): 3180 (br, 2NH); 1710, 1660 (2CO); 1438 (N=N); 1H NMR (200 MHz, CDCl3) d ppm: 1.39 (t, 3H, CH3, J = 6.9 Hz), 1.78-1.82 (m, 4H, C6-2H, C7-2H), 2.23 (s, 3H, CH3), 2.66-2.81 (m, 4H, C4-2H, C7-2H), 4.26 (q, 2H, CH2, J = 6.9 Hz), 8.42 (br, 1H, NH), 14.45 (br, 1H, NH, hydrazone); MS: m/z (%) = 336 (M++2, 2.6), 335 (M+ + 1, 7.8), 334 (M + , 100), 305 (2.5), 288 (28.5), 287 (53.6), 259 (32.8), 241 (23.3), 225 (35.5), 221 (15.7), 213 (9.3), 179 (56.5), 175 (22), 151 (22.2), 122 (7.3), 95 (1.6), 84 (7.3), 73 (5.9). Element. analysis: Calc. C15H18N4O3S: %C = 53.88; %H = 5.43; %N = 16.75. Found: %C = 53.83; %H = 5.41; %N = 16.77.

All melting points were determined on Gallenkamp electric melting point apparatus. TLC analysis was carried out on silica gel 60 F254 precoated aluminum sheets. Infrared spectra were recorded on Mattson 5000 FTIR spectrometer (k, cm-1) using potassium bromide Wafer technique at the Microanaly-tical Unit, Faculty of Science Mansoura University. The 1H-NMR spectra were determined on a Varian XL 200 MHz at the Microanalytical Center (Cairo University, Giza, Egypt) using CDCl3 or DMSO as solvent and TMS as an internal standard. The mass spectra (EI) were recorded on 70 eV with Kratos MS equipment at the Microanalytical Center (Cairo University, Giza, Egypt). Elemental analyses (C, H and N)

4.2.2. (E)-2-(2-(3-Methyl-5-oxo-1H-pyrazol-4(5H)-ylidene)hydrazinyl)-4,5,6,7-tetra-hydrobenzo[b]thiophene-3-carboxamide (5b)

Brown powder; Yield: 98%; mp: 260 0C; IR (KBr, v cm-1): 3406, 3390, 3370, 3315, 3233 (2NH, NH2), 1666, 1653 (2CO), 1440 (N=N); 1H NMR (200 MHz, DMSO-d6) d ppm: 1.32 (t, 3H, CH3, J = 6.9 Hz), 1.66-1.75 (m, 4H, C5-2H, C6-2H), 2.30 (s, 3H, CH3), 2.67-2.83 (m, 4H, C4-2H, C7-2H), 7.21 (br, 2H, NH2), 8.84 (br, 1H, NH, pyrazole), 11.42 (br, 1H, NH, hydrazone); MS: mjz (%) = 307 (M++2, 1), 306 (M+ + 1, 2), 305 (M + , 8), 279 (44), 272 (9), 259 (20), 238 (18), 217 (19), 206 (16), 193 (39), 179 (95), 149 (100), 122

(22), 103 (95), 91 (27), 74 (48), 57 (28). Element. analysis: Calc. C13H15N5O2S: %C = 51.13; %H = 4.95; %N = 22.94. Found: %C = 51.15; %H = 5.02; %N = 22.98.

4.2.3. (E)-2-(2-(3-Methyl-5-oxo-1H-pyrazol-4(5H)-ylidene)hydrazinyl)-4,5 ,6 ,7-tetra-hydrobenzo[b]thiophene-3-carbonitrile (5c)

Black powder; Yield: 97%; mp: 187 0C; IR (KBr, v cm-1): 3326, 3186 (2NH), 2200 (CN), 1486 (N=N); 1H NMR (200 MHz, DMSO-d6) d ppm: 1.70-1.77 (m, 4H, C5-2H, C6-2H), 2.35 (s, 3H, CH3), 2.69-2.88 (m, 4H, C4-2H, C7-2H), 8.59 (br, 1H, NH, pyrazole), 11.60 (br, 1H, NH, hydrazone); MS: m/z (%) = 289 (M++2, 0.8), 288 (M+ + 1, 7.8), 287 (M + , 42.2), 279 (10.4), 241 (6.5), 240 (38.3), 212 (26.3), 200 (4.9), 192 (11.2), 178 (53.6), 177 (73.2), 163 (23.7), 150 (100), 146 (23.7), 135 (57.3), 113 (3.6), 91 (11.7), 80 (8.6), 69 (14.6), 60 (7.6). Element. analysis: Calc. C13H13N5OS: %C = 54.34; %H = 4.56; %N = 24.37. Found: %C = 54.38; %H = 4.53; %N = 24.35.

4.3. General procedure for the synthesis of 5d-f and 6a-c

A well stirred solution of 2-aminothiophenes 1a-c (0.005 mol) in 3.6 mL of conc. HCl and 1 mL of H2O was cooled in an ice-bath and diazotized with the solution of 0.345 g NaNO2 (0.005 mol) in 2 mL of H2O. The cold diazonium solution was added slowly to a well stirred solution of 3-methyl-1-phe-nyl-1 H-pyrazol-5(4H)-one (3b) (0.8 g, 0.005 mol) or 3-amino-1H-pyrazol-5(4H)-one (4) (0.49 g, 0.005 mol) in 30 mL of ethanol containing sodium acetate (2 g, 0.025 mol). The reaction mixture was stirred for another 2 h. The crude product was filtered off, dried well and recrystallized from the suitable solvent to give compounds 5d-f and 6a-c, respectively.

4.3.1. (E)-Ethyl 2-(2-(3-methyl-5-oxo-1-phenyl-1H-pyrazol-4(5H)-ylidene) hydrazinyl)-4, 5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate (5d) Scarlet red powder; Yield: 70%; mp: 174 0C; IR (KBr, v cm-1): 3366 (NH, hydrazone), 1706, 1656 (2CO), 1496 (N=N); 1H NMR (200 MHz, CDCl3) d ppm: 1.42 (t, 3H, CH3, J = 6.9 Hz), 1.65-1.80 (m, 4H, C5-2H, C6-2H), 2.34 (s, 3H, CH3), 2.66-2.82 (m, 4H, C4-2H, C7-2H), 4.46 (q, 2H, CH2, J = 6.9 Hz), 7.14-8.03 (m, 5H, Ar-H), 14.71 (br, 1H, NH, hydrazone); MS: m/z (%) = 412 (M + +2, 3), 410 (M + , 0.2), 364 (4.5), 320 (10.8), 302 (1.9), 267 (2.2), 225 (7.2), 188 (3.1), 179 (12.1), 146 (2), 119 (6.6), 84 (14.4), 73 (27.6). Element. analysis: Calc. C21H22N4O3S: %C = 61.44; %H = 5.40; %N = 13.65. Found: %C = 61.40; %H = 5.47; %N = 13.69.

ysis: Calc. C19H19N5O2S: %C = 59.82; %H = 5.02; %N = 18.36. Found: %C = 59.85; %H = 5.10; %N = 18.31.

4.3.3. (E)-2-(2-(3-Methyl-5-oxo-1-phenyl-1H-pyrazol-4(5H)-ylidene)hydrazinyl)-4 , 5, 6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile (5f)

Orange powder; Yield: 98%; mp: 239 0C; IR (KBr, v cm-1): 3373 (br, NH), 2210 (CN), 1650 (CO), 1496 (N=N); 1H NMR (200 MHz, DMSO-d6) d ppm: 1.76-1.90 (m, 4H, C5-2H, C6-2H), 2.39 (s, 3H, CH3), 2.64-2.72 (m, 4H, C4-2H, C7-2H), 7.21-7.90 (m, 5H, Ar-H), 14.61 (br, 1H, NH, hydrazone); MS: m/z (%) = 365 (M++2, 8.2), 364 (M+ + 1, 22.6), 363 (M + , 100), 330 (2.5), 274 (3), 187 (2.6), 177 (38.2), 151 (2.9), 119 (6.1), 83 (6.4), 73 (16). Element. analysis: Calc. C19H17N5OS: %C = 62.79; %H = 4.71;%N = 19.27. Found: %C = 62.83; %H = 4.67; %N = 19.33.

4.3.4. (E)-Ethyl 2-(2-(3-amino-5-oxo-1H-pyrazol-4(5H)-ylidene)hydrazinyl)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate (6a)

Reddish brown powder; Yield: 97%; mp: 119 0C; IR (KBr, v cm-1): 3349, 3340, 3230, 3183 (NH2, 2NH), 1702, 1668 (2CO), 1627 (C=N), 1475 (N=N); 1H NMR (200 MHz, DMSO-d6) d ppm: 1.29 (t, 3H, CH3, J= 7.5 Hz), 1.71-1.73 (m, 4H, C5-2H, C6-2H), 2.61-2.70 (m, 4H, C4-2H, C7-2H), 4.28 (q, 2H, CH2O, J = 7.2 Hz), 5.85 (br, 2H, NH2), 10.71 (br, 1H, NH, pyrazole), 14.18 (br, 1H, NH, hydrazone); MS: m/z (%) = 336 (M+ + 1, 0.4), 335 (M + , 0.6), 297 (1.1), 239 (3.4), 225 (52), 221 (16.2), 210 (32.4), 196 (11), 181 (54.2), 179 (100), 174 (16.3), 151 (34.1), 137 (17), 118 (4.3), 96 (2.9), 84 (10.5), 65 (6.2). Element. analysis: Calc. C14H17N5O3S: %C = 50.14; %H = 5.11; %N = 20.88. Found: %C = 50.10; %H = 5.15; %N = 20.85.

4.3.5. (E)-2-(2-(3-Amino-5-oxo-1H-pyrazol-4(5H)-ylidene)hydrazinyl)-4,5,6,7-tetrahydro benzo[b]thiophene-3-carboxamide (6b)

Brown powder; Yield: 95%; mp: 141 0C; IR (KBr, v cm-1): 3397, 3338, 3247, 3180 (NH2, 2NH), 1660, 1633 (2CO), 1520 (N=N); 1H NMR (200 MHz, DMSO-d6) d ppm: 1.72-1.78 (m, 4H, C5-2H, C6-2H), 2.64-2.88 (m, 4H, C4-2H, C7-2H), 7.20-7.34 (br, 4H, 2NH2), 10.40 (br, 1H, NH, pyrazole), 13.03 (br, 1H, NH, hydrazone); MS: m/z (%) = 308 (M++2, 7.8), 307 (M+ + 1, 3.9), 306 (M + , 1), 279 (12.6), 220 (8.7), 210 (42.7), 196 (77.7), 178 (100), 175 (35), 164 (53.4), 151 (63.1), 125 (32), 110 (17.5), 85 (24.3), 69 (32). Element. analysis: Calc. C12H14N6O2S: %C = 47.05; %H = 4.61; %N = 27.43. Found: %C = 47.11; %H = 4.66; %N = 27.46.

4.3.2. (E)-2-(2-(3-Methyl-5-oxo-1-phenyl-1H-pyrazol-4(5H)-ylidene)hydrazinyl)-4 ,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxamide (5e)

Orange powder; Yield: 80%; mp: 298 0C; IR (KBr, v cm-1): 3428, 3220 (NH2, NH), 1728, 1635 (br, 2CO), 1498 (N=N); 1H NMR (200 MHz, DMSO-d6) d ppm: 1.72-1.79 (m, 4H, C5-2H, C6-2H), 2.67-2.72 (m, 4H, C4-2H, C7-2H), 7.18-7.90 (m, 8H, Ar-H, NH2, NH); MS: m/z (%) = 383 (M++2, 0.5), 382 (M+ + 1, 0.5), 381 (M + , 1), 363 (100), 343 (1.5), 306 (2), 273 (2.8), 243 (0.5), 210 (2.5), 177 (34.3), 158 (2), 119 (7.8), 90 (2.5), 84 (20.7), 73 (29.5), 63 (5.1). Element. anal-

4.3.6. (E)-2-(2-(3-Amino-5-oxo-1H-pyrazol-4(5H)-ylidene)hydrazinyl)-4,5,6,7-tetrahydro benzo[b]thiophene-3-carbonitrile (6c)

Brown powder; Yield: 98%; mp: >320 0C; IR (KBr, v cm-1): 3382, 3334, 3303, 3196 (2NH, NH2), 2195 (CN), 1668 (CO), 1513 (N=N); 1H NMR (200 MHz, DMSO-d6) d ppm: 1.741.80 (m, 4H, C5-2H, C6-2H), 2.71-2.79 (m, 4H, C4-2H, C7-2H), 7.21 (br, 2H, NH2), 10.80 (br, 1H, NH, pyrazole), 13.95 (br, 1H, NH, hydrazone); MS: m/z (%) = 288 (M + , 1.1), 255 (1.1), 243 (100), 240 (23.9), 128 (1.1), 114 (53.3), 111 (6.5), 67 (98.9). Element. analysis: Calc. C12H12N6OS:

%C = 49.99; %H = 4.19; %N = 29.15. Found: %C = 49.97; %H = 4.25; %N = 29.19.

4.4. Dyeing procedures

4.4.1. Preparation of dye dispersion

The required amount of the dye (2% shade) was dissolved in a suitable solvent (DMF) and added drop wise with stirring to a solution of Dekol-N (2 g/dm3), an anionic dispersing agent of BASF, then the dye was precipitated in a fine dispersion ready for use in dyeing.

4.4.2. Dyeing of polyester at 130 °C under pressure using fescaben as a carrier

The dye bath (1:20 liquor ratio) containing 5 g/dm3 5 g dm-3 Levegal PT (carrier of Bayer) as a carrier, 4% ammonium sulfate and acetic acid at pH 5.5, was brought to 60 °C. The polyester fabric was entered at this degree and run for 15 min. Two percentage of dye in the fine dispersion was added, temperature was raised to the boil within 45 min, dyeing was continued at the boil for about one hour, then dyed material was rinsed and soaped with 2% nonionic detergent to improve rubbing and wet fastness.

4.5. Assessment of color fastness

Fastness to washing, perspiration, light and sublimation was tested according to the reported methods.

4.5.1. Fastness to washing

A specimen of dyed polyester fabric was stitched between two pieces of un-dyed cotton fabric, all of equal diameters and then washed at 50 °C for 30 min. The staining on the un-dyed adjacent fabric was assessed according to the following grey scale: 1-poor, 2-fair, 3-moderate, 4-good, and 5-excellent.

4.5.2. Fastness to perspiration

The samples were prepared by stitching pieces of dyed polyester fabric between two pieces of un-dyed cotton fabric, all of equal diameters and then immersed in the acid medium for 30 min. The staining on the un-dyed adjacent fabric was assessed according to the following grey scale: 1-poor, 2-fair, 3-moderate, 4-good, and 5-excellent. The acid solution (pH 3.5) contains sodium chloride 10 g/l, lactic acid 1 g/dm3, disodium orthophosphate 1 g/dm3 and histidine monohydrochlo-ride 0.25 g/dm3.

4.5.3. Fastness to rubbing

The dyed polyester fabric was placed on the base of Crocke-teer, so that it rests flat on the abrasive cloth with its long dimension in the direction of rubbing. A square of white testing cloth was allowed to slide on the tested fabric back and forth twenty times by making ten complete turns of the crank. For wet rubbing test, the testing square was thoroughly wet in distilled water. The rest of the procedure is the same as the dry test. The staining on the white testing closed was assessed according to grey scale: 1-poor, 2-fair, 3-moderate, 4-good, and 5-excellent.

4.5.4. Fastness to sublimation

Sublimation fastness was measured with an iron tester (Yas-uda No. 138). The samples were prepared by stitching pieces

of dyed polyester fabric between two pieces of un-dyed polyester, all of equal diameters and then treated at 180 °C and 210 °C for 1 min. Any staining on the un-dyed adjacent fabric or change in tone was assessed according to the following grey scale: 1-poor, 2-fair, 3-moderate, 4-good, and 5-excellent.

4.5.5. Fastness to light

Light fastness was determined by exposing the dyed polyester on a Xenotest 150 (Original Hanau, chamber temperature 2530 °C, black panel temperature 60 °C, relative humidity 5060%, and dark glass (UV) filter system) for 40 h. The changes in color were assessed according to the following blue scale: 1-poor, 3-moderate, 5-good, and 8-very good.

4.6. Color assessment

Table 1 reported the color parameters of the dye fabrics assessed by tristimulus colorimetry. The color parameters of the dyed fabrics were determined on a spectromultichannel photodetector (model MCPD1110A), equipped with a D65 source and barium sulfate as a standard blank. The values of the chromaticity coordinates, luminance factor and the position of the color in the CIELAB color solid are reported.

4.7. Antitumor activity

Different concentrations of the tested compounds were prepared (ED100, ED50 and ED25 ig/mL DMSO), where ED is the effective dose. The amount of DMSO was adjusted to give a final concentration of 0.1%. Ascites fluid was obtained from the peritoneal cavity of the donor animal from (National Cancer Institute, Cairo, Egypt). The cells were grown partially floating and attach in a suspension culture (RPMI 1660 medium, Sigma Chemical Co. St. Louis, USA), supplemented with 10% fetal bovine serum (GIBCO, UK). They were maintained at 37 °C in humidified atmosphere with 5% CO2 for 2 h. The viability of the cell used in control experiments (DMSO only without drug) exceeded 95% as determined by microscopical examination using a hemocytometer and trypan blue stain (stain only the dead cells).

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