Molbank 2006, M479

http://www.mdpi.org/molbank/

 

Synthesis of 1-[3-(2-methyl-5-nitro-1H-imidazol-1-yl)propyl]-1H-1,2,3-benzotriazole and 1-[3-(2-methyl-5-nitro-1H-imidazol-1-yl)butyl]-1H-1,2,3-benzotriazole

 

Krystyna Nowak,  Maria Grzegożek*, Barbara Szpakiewicz

 

Institute of Organic Chemistry and Technology, Cracow University of Technology, ul. Warszawska 24, PL-31155 Kraków, Poland,

Tel/Fax (048-12) 628-20-37

e-mail: [email protected]

*Author to whom correspondence should be addressed

 

Received: 9 October 2005 / Accepted: 26 October 2005 / Published: 31 March 2006

 

Keywords:  1,2,3-benzotriazole derivatives, 2-methyl-5-nitroimidazole derivatives

 

 

The title compounds were obtained in reaction 1,2,3-benzotriazole (1) with 1-(3-chloropropyl)- (2a) and 1-(4-bromobutyl)-2-methyl-5-nitro-1H-imidazole (2b) [1].

The derivatives of 5-nitroimidazole show various interesting biological properties. They have good chemotherapeutic activity [2], are potent anti-bacterial agents [2] and are very effective against various infections especially antiprotozoic [3].

 

1-[3-(2-methyl-5-nitro-1H-imidazol-1-yl)propyl]- 1H-1,2,3-benzotriazole (3a)

A mixture of 1,2,3-benzotriazole (1) (commercial product) (0.76 g, 6.38 mmol), 1-(3-chloro- propyl)-2-methyl-5-nitro-1H-imidazole (1.58 g, 7.76 mmol) (2a) [1] and powdered anhydrous K2CO3 (2 g) and a catalytic amount of KI in dry DMF (25 mL) was stirred at room temperature for 24 h. The resulting solution was poured into water (100 mL) and precipitated solid was filtered off and washed with water. The crude product was purified by recrystallization from isopropyl alcohol giving 1-[3-(2-methyl-5-nitro-1H-imidazol-1-yl) propyl]-1H-1,2,3-benzotriazole (3a) as colorless needles (1.45 g,  79.5%).

 

Melting point: 167-169oC

 

1H-NMR (CDCl3, 80 MHz ): δ= 8.10 (dd, 1H, aromatic H, J = 8.96 Hz , J = 1.21 Hz), 7.80 (s, 1H, CH imid.), 7.32-7.57 (m, 3H, aromatic H), 4.70 (t, 2H, CH2­ CH2 -N-benzotriazole, J = 6.40 Hz), 4.04 (t, 2H, CH2­ CH2 -N-imid., J = 7.12 Hz), 2.66-2.35 (m, 2H, CH2 CH2­ CH2 ),  2.34 (s, 3H, CH3),

 

MS, (70eV) m/z (%): 286 (7.0), 269 (5.0), 171 (100).

 

IR (KBr, cm-1): 1537 and 1336 (NO2), 1495 (CH2), 1292 (C-N).

 

Elemental Analysis: Calculated for C13H14N6O2 (286.29): C 54.54, H 4.93, N 29.36; found C 54.23, H 4.87, N 29.02.

 

1-[3-(2-methyl-5-nitro-1H-imidazol-1-yl)butyl]-1H-1,2,3-benzotriazole (3b)

A mixture of 1,2,3-benzotriazole (1) (commercial product) (0.38 g, 3.19 mmol), 1-(3-bromo- butyl)-2-methyl-5-nitro-1H-imidazole (0.85 g, 3.43 mmol) (2b) [1] and powdered anhydrous K2CO3 (0.65 g) and a catalytic amount of KI in dry DMF (20 mL) was stirred at room temperature for 19 h. The resultating solution was poured into water (60 mL) and precipitated solid was filtered off, and washed with water. The crude product was purified by recrystallization from isopropyl alcohol giving 1-[3-(2-methyl-5-nitro-1H-imidazol-1-yl) butyl]-1H-1,2,3-benzotriazole (3b) as colourless needles (0.72 g,  75.2%).

 

Melting point: 168-170oC

 

1H NMR (CDCl3, 80 MHz ): δ= 7.93-7.34 (m, 4H, aromatic H), 7.66 (s, 1H, CH imid.), 4.81 (t, 2H, CH2­ CH2 -N-benzotriazole, J = 6.32 Hz), 3.91 (t, 2H, CH2­ CH2 -N-imid., J = 7.36 Hz ), 2.43-1.71 (m, 4H, CH2 CH2­ CH2 CH2 ),  2.37 (s, 3H, CH3).

 

IR (KBr, cm-1): 1539 and 1330 (NO2), 1496 (CH2) 1289 (C-N).

 

Elemental Analysis: Calculated C14H16N6O2 (300.32): C 55.99, H 5.37, N 27.98; found C 55.82, H 5.36, N 27.84.

 

References:

1. J.Bourdais, Bull. Soc. Chim., 1968, 3246.

2. K.Bhaumik, K.G.Akamanchi, J.Heterocyclic Chem., 41, 51(2004).

3. R.Silvestri, M.Artico, S.Massa, T.Marceddu, F.de Montis, P.La Colla, Bioorg.Med. Chem.Lett. 2000, 10, 253.

 

Sample Availability: Available from MDPI.

 

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