Synthesis and biological effects of new derivatives of benzotriazole as antimicrobial and antifungal agents

Abstract

Derivatives of 2-aminothiophene-3-carbonitrile, 2-thioxopyridine-3-carbonitrile, 1,8-naphthyridine-2one, thieno[2,3-b]pyridine-5-carbonitrile and thieno[2,3-d]pyrimidine incorporating with a 1H-b e n z otriazole moiety or 1,3,4-thiadiazole derivatives incorporating with a benzotriazol-1-ylmethyl group have been synthesized and tested for antimicrobial and antifungal activities. The structures of the newly synthesized compounds have been established on the basis of their analytical and spectral data. Pharmacological studies of the 1H-b e n z o t r i a z o l e nucleus have been shown to posses a variety of pharmacological activities such as anti-inflammatory [1], antimicrobial [2-4], anticonvulsant and CNS depressant [5] effects. Furthermore, several pharmacological studies have also pointed out the value of 2-aminothiophene [6,7], naphthyridine [8], thieno[2,3-d]pyrimidine [9,10], thieno[2,3b]pyridine [11] and thiadiazole [12] as biologically active nuclei. These findings focused on incorporating 2aminothiophene-3-carbonitrile, 2-thioxopyridine-3-carbonitrile, 4-amino-2-oxo-1,8-naphthyridine-3-carbonitrile, 4 -a m i n o t h i e n o [ 2 , 3 -b]pyridine-5-carbonitrile and thieno[2,3-d] pyrimidine with 1H

Novel synthesis of thieno[2,3‐b]pyridine and substituted 2‐thienylthiourea derivatives as antibiotic agents

“…Treatment of compound 2 with ethyl cyanoacetate (7a) in refluxing ethanol may produce either 6-oxo-thieno [2,3-b]pyridine (9) or the thieno [2,3-d]pyrimidine (10) similar to that which has recently been reported from our laboratories [14]. In fact, only a single product was obtained and confirmed by TLC.…”

“…All the 4,5-dihydrothieno [2,3-b]pyridine derivatives 6a,c,d as well as the 2-aminothiophene derivative 2 showed stronger activity against antibacterial and fungicidal activity ( Table 1). It was interesting that 2-(2'amino-3-cyanothien-4'-ylmethyl)-phthalimide 2 showed stronger activity against some types of bacteria than that of 2-amino-5-benzotriazol-1-yl-4-methylthiophene-3-carbonitrile, which has been reported recently from our laboratories [14]. A mixture of 1 (2.03 g, 10 mmol) malononitrile (0.66 g, 10 mmol) elemental sulfur (0.32 g, 10 mmol) in DMF (20 mL) and few drops of piperidine was refluxed for 3 hours.…”

“…Structure 10 was ruled out on the basis of its elemental analysis and spectroscopic data. [14], supports structure 9 and again discounts structure 10. Moreover, the ir spectrum revealed the presence of NH 2 and NH stretching bands at ν max 3394-3206 cm −1 and CN group stretching at 2205 cm −1 in addition to three carbonyl stretching bands at 1771, 1714 and 1629 cm −1 , respectively which can be assigned to the symmetric and asymmetric phthalimide carbonyl and the pyridine carbonyl stretching bands.…”

“…Therefore, in a continuation of our efforts to generate new synthetic routes to different polyfunctional thiophenes [11][12][13][14] we have used Gewald's reaction [15] for the synthesis of 2-(2'-amino-3'-cyanothien-4'-ylmethyl)phthalimide (2). Hence, compound 2 is obtained in situ via a one step process by treatment of 1 with malononitrile in refluxing dimethylformamide in the presence of elemental sulfur and a catalytic amount of piperidine.…”

Simultaneous displacement of a nitro group during coupling of diazotized o-nitroaniline with phenols

“…Among others, benzotriazole derivatives are prepared from o-nitroanilines via formation of diazonium ion, followed by diazo-coupling with phenol and reduction [8][9][10][11]. Some of the benzotriazols have significant pharmacological activities [12][13][14][15]. Derivatives of 2-aryl-2H-benzotriazole have been utilized as building blocks in the preparation of ultraviolet light absorbers [11,[16][17][18][19].…”