J. Chem. Tech. Biotechnol. 1992, 55, 355-360

s-Triazole Systems. Part IV : Novel Substituted Thio-s-Triazole Derivatives Ibrahim M. A. Awad,* Etify A. Bakhite & Abdu E. Abdel-Rahman Chemistry Department, Faculty of Science, Assiut University, Assiut, Egypt (Received 8 April 1992; revised version received 12 June 1992; accepted 1 July 1992)

Abstract: Interaction of (3-aryloxymethyl-4-phenyl-s-triazol-5-yl)thioacethydrazide (la-c) with phenyl isocyanate and/or with methyl/phenyl isothiocyanate gave semicarbazides (2a-c) and thiosemicarbazides (3a-f) respectively. Cyclization of (3a-f) yielded s-triazoles (4a-f). Compounds 4b,d,f were easily alkylated giving S-substituted thio-s-triazoles (5a-e). Furthermore, compounds 4b,d,f underwent a Mannich reaction to give the expected Mannich bases (6a-f). A11 compounds were fully confirmed by elemental and spectral analyses and have been screened in uitro for antimicrobial activity. Key words : semicarbazides, thiosemicarbazides, s-triazoles, Mannich bases, biological activity.

INTRODUCTION

with phenyl isocyanate gave 1-(3'-aryloxymethyl-4'phenyl-s-triazol-5'-yl)thioacetyl-4-phenyl-3-semicarbazides (2a-c). Similarly la-c were reacted with methyl/ phenyl isothiocyanate to give the corresponding thiosemicarbazides (3a-f) in nearly quantitative yields.

Some thiosemicarbazides and mercapto-s-triazoles are reported to possess antibacterial,'*' antif~ngal,~.anti~ i r a l ,antidiabeti~,~ ~.~ insecticidal' and schistosomicidal Also, the pharmacological properties of acti~ities.~ Mannich bases and their derivatives are well known." In view of these facts and as a continuation of our earlier work on the synthesis of new mercapto-s-triazoles,1"3 we report herein the synthesis of some more interesting

SCH2CONHNHCONHPh Ph 2a-c

-R

derivatives, containing an s-triazole nucleus attached to other biologically active residues derived from (s-triazol5-y1)thioacethydrazides la-c and the testing of the biological activity of some of them.

-R a, H b, CH3

jF-l R 0 0 C H 2

c, C I

SCH2CONHNHCSNHR

I Ph 3a-f

RESULTS AND DISCUSSION The starting compounds, (3-aryloxymethyl-4-phenyl-striazol-5-y1)thioacethydrazides(la-c) were prepared according to our previous method." Treatment of la-c

*

b

s

H

R' CH3 C6H5

c

I

CH3 CH3 CI CI

CH3 CgH5 CH3 c6H5

a

To whom correspondence should be addressed.

Schemes 1-3

355 J . Chem. Tech. Biotechnol. 0268-2575/92/$05.00 0 1992 SCI. Printed in Great Britain

d o f

R ,H

, , ,

'

I. M . A . Awad, E. A. Baklzite, A . E. Abdel-Rahnian

356

mercapto-s-triazoles synthesized exhibited variable acCyclization of 3a-f by heating in sodium hydroxide solution (8 YO)yielded 3-aryloxymethyl-4-phenyl-5-(4’- tivities against the bacteria used (inhibition zones ranged phenyl-5’-thiono-s-triazol-3’-ylmethyl)thio-s-triazolesfrom 20 to 110 mm). It appears that all thiosemicarbazide derivatives 3a-f and S-substituted thio-s-triazole (4a-f) which exist in thione-thiol tautomeric mixture as compounds 4a-f have more potent activities than the indicated from their reactions. thioacetyl-hydrazides la-c and semicarbazide derivatives (inhibition zones ranged from 60 to 130 mm). The compounds also possessed variable and pronounced antifungal activities (inhibition zones Ph R‘ 10-120 mm). Compounds 4a-f (di-s-triazole derivatives) 4a-f are more active than the starting compounds. Mannich bases 6a-f showed a higher activity against Pmicilliuni chrysogenum than the other fungi.

EXPERIMENTAL

Scheme 4

Thus, interaction of 4b,d,f with such alkylating agents as ethyl iodide, phenacyl bromide and chloroacetanilide in refluxing ethanol containing sodium acetate led to the formation of S-substituted thio-s-triazoles (5a-e) in good yields. Also. compounds 4b,d,f were reacted with piperidine and/or morpholine in the presence of formaldehyde, under Mannich reaction conditions producing the corresponding Mannich bases (6a-d) in excellent yields. Antimicrobial results The results obtained from the antibacterial screens revealed that some of the thiosemicarbazides and

All melting points are uncorrected. IR spectra were run on a Pye-Unicam SP 3-100 spectrophotometer using a KBr disc technique (wavenumbers in cni-’). ‘H-NMR spectra were recorded on a Varian EM-390 90 MHz spectrometer in a suitable deuterated solvent using TMS as internal standard; chemical shifts are given in ppm (6scale). Melting points, yields and analytical data of all novel compounds are given in Table 1. Synthesis of 1-(3’-aryloxymethyl-4’-phenyl-s-triazol-5’yl)thioacetyl-4-phenyl-3-semicarbazides (2a-c) A mixture of la-c (5 mmol) and phenyl isocyanate (0.55 cm3, 5 mmol) in absolute ethanol (30cm“) was refluxed for 3 h. White crystalline products obtained on cooling were recrystallized from ethanol as white crystals of 2a-c.

TABLE 1 Melting Points, Yields and Analytical Data of the New Compounds Compound No.

m.p. (“C)

Yield (Yo)

Molecular ,formula

Analytical data Calculatrdlfbund (YO) C

2a

166

95

C,,H,,N,O,S (474.54)

2b

182

92

2c

200

89

C,,H,,N,O,S (488.57) C,,H,,ClN,O,S (508.99)

3a

170

91

C,,H,,,N,O,S, (428.54)

3b

185

95

C,,H,,N,O,S, (490.6 1)

3c

210

93

C,,H,,N,O,S, (442.56)

3d

190

94

C,,H,,N,O,S, (504.64)

60.74 60.80 61.46 61.50 56.64 56.70 53.25 53.20 58.76 58.80 54.28 54.30 59.50 59.47

H

N

S

C

4.67 4.70 4.95 5.00 4.15 4.20 4.70 4.72 4.52 430 5.01 5.00

17.71 17.65 17.20 17.00 16.51 16.50 19.61 19.60 17.13 17.10 18.99 19.00

6.76 6.70 6.56 6.50 6.30 6.25 14.96 13.07 13.10 14.49 1430

4.79 4.82

16.65 16.70

12.71 12.65

15.00

I

6.96 7.00

Novel substituted thio-s-triazole derivatives

357 TABLE I -contd.

Compound No.

m.p. ("C)

Yield (%)

~

Molecular formula

Analytical duta Calculated/ found (YO) C

H

N

S

~~

3e

183

97

49.29 49.30

4.14 4.10

18.15 13.85 18.20 13.80

3f

194

98

5490 55.00

4.03 4.00

16.01 16.00

12.21 12.30

4a

240

82

55.59 55.60

20.47 20.50

15.62 15.60

4b

165

83

17.78 17.80

13.57 13.60

4c

250

85

4.42 4.50 4.26 4.30 5.59 5.60 4.56 4.60 3.85 3.90 3.78 3.80 5.09 5.10 4.44 4.50 4.67 4.60 4.03 4.00 472 4.68 5.48 5.52

23.32 23.40

17.79 17.70

17.27 17.30 18.89 18.80 16.57 16.50 16.33 16.30 14.23 14.20 13.90 14.00 13.44 13.40 15.82 15.80 17.21 17.30 17.15 17-20 16.80 16.75

13.18 13.10 14.41 14.40 12.65 12.70 12.46 12.48 10.85 10.90 10.60 10.55 10.26 10.30 10.35 10.44 11.26 11.20 11.22 11.20 10.98 10.90

16.73 16.80 16.56 16.50 16.17 16.20

10.95 11.00 10.83 10.80 10.58 10.60

C,,H,,N,OS, (472.59)

60.99 61.09

C20H2!JN60S2

66.65 66.42

(360.42)

4d

205

85

4e

236

87

C,,HI7C1N,OS, (444.97)

4f

206

86

C,,H,,CIN,OS, (507.04)

5a

105

78

C,,H,,N,OS, ( 5 14.68)

5b

191

75

C,,H,,N,O,S2 (590.73)

5c

196

70

C,,H,,NtiO,S, (604.76)

5d

200

80

C,,H,,CIN,O,S, (625 18)

5e

140

71

C,,H,,NiO,S, (619.77)

6a

96

69

6b

89

73

6c

110

73

C,lH:l,N7OS, (583.78)

6d

141

75

C,"H,,N7O,S, (585.76)

6e

143

78

C,,H,,,CIN,OS, (592.19)

6f

148

71

C,,H,,N,OS, (486.62)

7OS2 (569.76)

C3UH:llN

C,,H,,ClN,O,S, (606.17)

61.71 61.68 51.29 51.30 56.85 56.90 66.51 66.50 65.06 65.00 65.54 65.60 61.48 61.55 63.95 63.90 63.24 63.30 60.92 61.01 63.78 63.82 61.52 61.60 58.82 56.00 57.46 57.50

5.11

5.10 5.70 5.70 5.33 5.40 5.1 I

5.10 4.66 4.60

TABLE 2 Important IR Bands of the Synthesized Compounds Assignment

"NH 'C=o "=S

2a-c

3a-f

4a-f

5a

3340,3285 1710,1670

3360,3200 1720 1200

3100

-

-

-

1680

3300 1660

1300

-

-

-

-

5b-d ~

5a

6a-f ~

~

1330

I. M . A . Awad, E. A . Bakhite, A . E. Abdel-Rahman

358

TABLE 3 ’H-NMR Spectra of Representative Examples of the Prepared Compounds Compound (solvent)

-SCH,

Other signals

Aromatic protons (m)

-OCH2-

(4

(8)

6.40-7.60 (14H)

5.00

4.00

6.50-7.70 (14H)

5.10

4.10

6.40-7.60 (9H)

5.00

4.00

6.50-7.50 (15H)

4.80

4.30

6.40-7.60 (14H)

5.00

4.20

6.50-7.50 (19H)

4.80

6.50-7.50 (14H)

4.80

4.30“ 2.20 (s, 3H, CH,) 3+30b 15.00 (s, 1H, CONH and exchangeable with D,O) 4.30 2.20 (s, 3H, CH,) 5.00 (s, 2H, NCH,N), CH,-

2.20 (s, 3H, CH,) -

2.20 (s, 3H, CH,), 3.00 (s, 3H, CSCH,) 13.50 (s, IH, NH and exchangeable with D,O) 2.20 (s, 3H, CH,)

/ 2.75 (t, 4H, N

1 3

\ CH,CH,-

/ 3.60 (t, 4H, 0

1 3

\

6.60-7.50 (14H)

4.90

4.30

CH,5.05 (s, 2H, NCH,N), CH,-

/ 2.70 (t, 4H, N

\ CH,CH,-

/ 3.60 (t, 4H, 0

)3

\ CH,a,b

Two singlets corresponding to two methylene groups (SCH,CONH and SCH,).

Synthesis of 1-(3’-aryloxymethyl-4-phenyl-s-triazol-Syl)thioacetyl-4-substituted-3-thiosemicarbazides(3a-f)

Synthesis of 3-aryloxymethyl-4-phenyl-5-(4-phenyl-5’thiono-s-triazol-3’-yl-methyl)thio-s-triazoles(4a-f)

A mixture of la-c (10mmol) and methyl/phenyl

A solution of 3a-f (5 mmol) in aqueous sodium hydroxide 8 % (10 cm3) was heated on a water bath for 4 h. After cooling, the solution was filtered and adjusted to pH 5-6 with dilute HCl at 5-10°C. The crude product was filtered, washed with water and recrystallized from ethanol to give 4a-f.

isothiocyanate (10 mmol) in absolute ethanol (30 cm3) was refluxed for 3 h. After cooling, the solid thus formed was collected and recrystallized from ethanol as white needles of 3a-f.

Novel substituted thio-s-triazole derivatives

359

TABLE 4 Biological Screening Data of the Synthesized Compounds (inhibition zones in mm) Antibacterial activity

Compound

Antifungal activity

No.

Staphylococcus Serratia Bacillus Pseudomonas aureus marcescens cereus aeruginosa DSM 346 DSM 1608 DSM 345 DSM 1299

la lb lc 3a 3b 3c 3d 3e 3f 4a 4b

4c 4d 4e 4f 5a 5b 5c 5d 5e 6a 6b 6c 6d

6e 6f

20 - ve 35

70 90 80 70 120 110 40 55 75 80 115 130 40 55 25 120 65 70 85 60 75 95 105

- ve - ve

25 30 40 60 50 70 85

ve

-

35 - ve

50 95 80 -

ve

25 -

ve

30

-ve

- ve - ve

20 50 60 55 80 50 125 120 70

40 35 70 35

105 90 -ve

45 35 - ve

105 75 -

ve

45 - ve

95

115

- ve

- ve - ve

40 - ve 35 - ve

50 65

35 50 60 65 85

- ve

45 55 115 125 30 65 35 130 45 - ve

ve - ve -

50 55 75

Penicillium chrysogenum Thom AUCC-530

Candida Aspergillus albicans flavus (Robin) Berkho Link AUCC-164 AUCC-I 720

- ve - ve

- ve

- ve

20

50 80 110 90 105 130

- ve - ve 35 - ve

30 45 45 60

I10 60 55 70 55 95 85 40 85 65 105 35 80 75 90 85

120 135

45 90 85

- ve

- ve

60 85 90 45

35

-ve

- ve

- ve

40 70 115

85 125 135

- ve - ve - ve

-

90 - ve 35 -

ve

40 50 65 85

ve

70 - ve

105 70 - ve

35 - ve

45 80 95

AUCC-Assiut University Culture Collection. DSM-Deutsche Sammlung von Mikroorganismen.

Schemes 5-6 24

CTB 55

3 60

Alkylation of compounds 4b,d,f; formation of compounds 5a-e: General procedure A mixture of 4b,d,f (10 mmol), the respective halocompound (10 mmol) and sodium acetate (15 mmol) in ethanol (30cm3) was reffuxed for 1 h. On cooling, the solid thus precipitated was collected and recrystallized from ethanol giving compounds 5a-e.

Synthesis of 3-aryloxymethyl-4-phenyl-5-(4’-phenyl-l’piperidino/morpholino methyl-S’-thiono-s-triazol-3’y1)methyl thio-s-triazoles (6a-f) To a mixture of 4b,d,f (10 mmol) and piperidine and/or morpholine (10 mmol) in absolute ethanol (50 cm3), formalin solution (37 YO)(1 cm3)was added. The contents were stirred for 1 h, then refluxed for a further hour. It was left overnight at room temperature, the product thus precipitated was collected and recrystallized from ethanol to give compounds 6a-f. Biological screening : antibacterial and antifungal activities Substituted thio-s-triazole compounds were screened in zitro for their antibacterial activities against : Staphyloc m w s aureus DSM 346, Serratia marcescens DSM 1608, Bucillus cereus DSM 345 and Pseudomonas uevuginosa DSM 1299 and also for their antifungal activities against : Penicillium chrysogenum, Thom AUCC-530, Cundidu ulbicans (Robin) Berkho AUCC1720 and AspergiNus flaws Link AUCC- 164. The disc-diffusion method was used to measure the antimicrobial activity.14-lRThe tested compounds were dissolved in sterile dimethylformamide and added at a concentration of 0.5 mg per disk (Whatman No. 3 filter paper, 0.5 cm diameter). The culture medium for bacteria was nutrient agar (NA) (composed of beef extract, 3 g;

I. M . A . Awad, E. A . Bakhite, A . E. Abdel-Rahman

peptone, 5 g ; agar, 15 dm3, and adjusted to pH 7 before sterilization at 121°C for 20 min). Glucose-Czapek’s agar medium (NaNO,, 2 g; KH,PO,, 1 g; MgSO, .7H,O, 0.5 g; KCl, 0.5 g; glucose, 10 g; agar, 15 dm-3 distilled water) was used for fungi. The inoculated plates were incubated a t 37f 1°C for 24-28 h in the case of bacteria and at 28°C for 7-8 days in the case of fungi. The inhibition zones of microbial growth produced by different compounds were m e a ~ u r e d . ’ ~ - l ~

REFERENCES 1. Dewani, M. B., Pathak, V. S. & Amine, V. M., Indian J. Chem., 11 (1973) 1078. 2. Postvskii, Y. & Vereschagina, N. N., Zhur. Ohschei. Khim., 26 (1956) 2583; Chem. Ahstr., 51 (1957) 5055. 3. Bhat, A. K., Bhamaria, R. P., Bellare, R. A. & Deliwala,

C. V., Indian J. Chem., 5 (1967) 397. 4. Pesson, M., French Patent I 273 881 ; Chem. Abstr., 57 (1962) 9860f. 5. Misra, V. S. & Agarwal, N. S., Indian J . Appl. Chern., 32 (1969) 335. 6. Shah, M. H., Mhas/Kar, M. Y., Varya, N. A,, Bellare, R. A. & Deliwala, C. V., Indian J. Chem., 5 (1967) 391. 7. Farbwerke Hoechst AG, Belg. Patent, 632 263, 18 Nov. 1963; Ger. Appl. 12 May, 1962, 6 pp. 8. Bowen, C. V., US Patent 2 403 395, 1946. 9. Soliman, R. & Hammouda, A. N., J. Pharm. Sci., 68 (1979) 1377; Chem. Abstr., 92 (1980) 191183~. 10. Mannich, C. & Honig, P., Arch. Pharm., 265 (1927) 298. 11. Abdel-Rahman, A. E., Awad, I. M. A. & Bakhite, E. A., Phosphorus, Sulfur & Silicon, 48 ( I ) (1990) 289. 12. Awad, I. M. A., Abdel-Rahman, A. E. & Bakhite, E. A., Phosphorus, Sulfur & Silicon, 54 ( 2 ) (1990) 63. 13. Awad, I. M. A., Abdel-Rahman, A. E. & Bakhite, E. A., J . Chem. Tech. Biotechnol., 51 (3) (1991) 483. 14. British Pharmacopoeia. Pharmaceutical Press, London, 1953, p. 796. 15. Chatuvedi, K. K., Jain, N. K., Jain, P. & Kaushal, R., Indian Drugs, 15 (1978) 57. 16. Sleight, J. D. & Timburg, M. C . Notes on Medical Bacteriology. Churchill Livingstone, USA, I98 I , p. 43.