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Original article
11 (
1
); 137-142
doi:
10.1016/j.arabjc.2014.07.014

Novel derivatives of 5,6-dimethoxy-1-indanone coupled with substituted pyridine as potential antimicrobial agents

, , ,
a Department of Chemistry, Saurashtra University, Rajkot, Gujarat, India
b Research Scholar, JJT University, Jhunjhunu 333001, Rajasthan, India
c School of Chemistry, University of KwaZulu-Natal, Westville Campus, Durban 4000, South Africa

⁎Corresponding author. Tel.: +91 9898066667. nilay1381@gmail.com (Nilay D. Bhatt)

Received: , Accepted: ,
© The Author(s) 2014
Disclaimer:
This article was originally published by Elsevier and was migrated to Scientific Scholar after the change of Publisher.

Peer review under responsibility of King Saud University.

Abstract

Synthesis of novel derivatives of 5,6-dimethoxy-1-indanone was carried out via its Schiff’s base using 2-cyanoacetohydrazide followed by cyclization with 2-arylidenemalononitrile in the presence of a catalytical amount of piperidine to get 6-amino-1-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylideneamino)-2-oxo-4-aryl-1,2-dihydropyridine-3,5-dicarbonitrile derivatives. The structures of the synthesized compounds were confirmed on the basis of their spectral and elemental analysis. The synthesized compounds were also screened for antimicrobial activity and found to have promising antibacterial activity.

Keywords

Cyclocondensation
2-Cyanoacetohydrazide
2-Arylidenemalononitrile
1,2-Dihydropyridine
1

1 Introduction

The pyridine nucleus is of considerable interest as this ring is the key constituent in a range of bioactive compounds, both naturally occurring and synthetic, and often of considerable complexity (Boger and Nakahara, 1991). The pyridine dicarbonitrile substructure was therefore chosen as a basic structural scaffold for the design of a reaction-based library (Reddy et al., 2006). Many publications report the biological properties of pyridinedicarbonitriles as being antihypertensive (Ward, 1976), antihistaminic (Quintela et al., 1997), anticancer, (Cocco et al., 2007) anti-inflammatory, analgesic (Manna et al., 1992), antibacterial (Behbehani et al., 2012), anti-HIV agents (El-Hawash et al., 2006) and anti-Alzheimer (Samadi et al., 2010). Many derivatives of pyridine-3,5-dicarbonitrile are reported as potential therapeutic agents, In hope to discover novel therapeutic agents, a series of 6-amino-1-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylideneamino)-2-oxo-4-aryl-1,2-dihydropyridine-3,5-dicarbonitrile compound are prepared which have not been reported before and compounds are tested for their antibacterial and antifungal activities.

2

2 Experimental

2.1

2.1 Materials and methods

Melting points were determined in open capillary tubes and are uncorrected. NMR was recorded either in CDCl3 or DMSO-d6 on a Bruker Avance 400 Hz and signal is given in ppm (δ) relative to TMS. Elementary analyses were taken on Euro EA 3000 elementary analysis instrument. LCMS were measured on Agilent 1100 Series MS spectrometer. TOF MS were measured on a Waters ZQ 2000 spectrometer. All the solvent and materials are of reagent grade and purified before use. Purity of all reagent and product was checked by TLC (hexane:ethylacetate; 70:30).

2.2

2.2 Procedure for the preparation of 2-cyano-N′-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylidene)acetohydrazide (2)

To the mixture of (0.0026 moles) of 5,6-dimethoxy-1-indanone and 15.0 ml Ethanol, (0.0026 moles) of 2-cyanoacetohydrazide is heated to reflux temperature, to the suspension and 1–2 drops of conc. hydrochloric acid is added, reaction mixture was refluxed till disappearance of raw material. Completion of reaction was monitored by TLC (hexane:ethylacetate:methanol; 5:5:2). Solid was collected by filtration and recrystallized with ethanol.

2.3

2.3 General procedure for the preparation of 2-arylidenemalononitrile 3(a–k)

The mixture of aromatic aldehydes (0.03 moles), malononitrile (0.03 moles) and (piperidinecatalytic amount) in 35 ml ethanol was stirred at room temperature for 1.5 h. The precipitate is allowed to stand overnight, collected by suction filtration washed with cold ethanol, and finally dried at the room temperature. Used for successive step without purification. Purity of all the compounds has been checked by TLC and compared with reported mp (Sakurai et al., 1972).

2.4

2.4 General procedure for the preparation of 6-amino-1-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylideneamino)-2-oxo-4-aryl-1,2-dihydropyridine-3,5-dicarbonitrile derivatives 4(a–k)

To a solution of 2 (2 mmoles) in ethanol (10 ml) was added the appropriate 2-arylidenemalonitrile (3a–3k) (2 mmoles) and four drops of piperidine. The mixture was refluxed 3–5 h. The mixture was cooled and the separated crystalline product was filtered, washed with ethanol, dried and recrystallized from ethanol.

2.5

2.5 Characterization of synthesized Compounds

2.5.1

2.5.1 2-cyano-N′-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylidene)acetohydrazide (2)

Off white solid; Yield: 620 mg (87%), mp 230–231 °C, 1H NMR (400 MHz,CDCl3) δ ppm = 9.22 (s, 1H, NH), 7.15 (s, 1H, ArH), 6.56 (s, 1H, ArH), 3.91 (d, J = 1.6 Hz, 6H,2OCH3), 3.80 (s, 2 H,CH2CN), 3.07 (t, 2 H,CH2), 2.88 (t, 2 H,CH2), 13C NMR (40 MHz, CDCl3) δ ppm = 160.3, 156.0, 151.3, 147.9, 139.4, 125.7, 116.2, 110.9, 105.9, 56.5, 56.4, 28.8, 27.8, 24.2., IR (cm−1): 2214, 2935, 1680, 1329., m/z: 274.11, Anal. Cald for C14H15N3O3: C, 61.53; H, 5.53; N, 15.38; O, 17.56; Found: C, 61.53; H, 5.53; N, 15.38.

2.5.2

2.5.2 6-Amino-1-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylideneamino)-4-(4-methoxyphenyl)-2-oxo-1,2-dihydropyridine-3,5-dicarbonitrile (4a)

Orange powder, Yield: 330 mg (40%), mp 236–238 °C, 1H NMR (400 MHz, DMSO-d6) δ ppm = 10.35 (s, 3 H, NH2),7.77–7.75 (d, 1H, ArH), 7.05 (s, 1H, ArH), 7.02–7.01 (d, 1H, ArH), 6.84 (s, 1H, ArH), 3.92 (s, 6 H, 2OCH3), 3.85 (s, 3 H, OCH3), 3.10–3.07 (t, 2 H, indane CH2), 2.65–2.62 (t, 2 H, indane CH2) ppm; 13C NMR (40 MHz, DMSO-d6) δ ppm = 166.0, 161.9, 160.4, 155.0, 148.5, 142.4, 128.9, 128.8, 127.2, 117.1, 113.9, 110.1, 106.8, 82.1, 71.1, 56.5, 56.4, 55.2, 29.5, 28.1 ppm; LCMS: m/z 454.5 (M+), Anal. Cald for C25H21N5O4.

2.5.3

2.5.3 6-Amino-1-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylideneamino)-2-oxo-4-phenyl-1,2-dihydropyridine-3,5-dicarbonitrile (4b)

Grey powder, Yield: 280 mg (36%), mp 218–221 °C, 1H NMR (400 MHz, DMSO-d6) δ ppm = 10.02 (s, 2 H, NH2), 8.04–8.01 (d, 1H, ArH), 7.57–7.52 (t, 1H, ArH), 7.29–7.25 (t, 1H, ArH), 7.04 (s, 1H, ArH), 6.84 (s, 1H, ArH), 3.92 (s, 6 H, 2OCH3), 3.10–3.07 (t, 2 H, indane CH2), 2.66–2.62 (t, 2 H, indane CH2) ppm; 13C NMR (40 MHz, DMSO-d6) δ ppm = 166.4, 160.4, 155.0, 151.0, 150.3, 148.5, 133.9, 131.0, 129.3, 128.9, 128.7, 117.0, 113.6, 110.1, 106.8, 91.9, 71.6, 56.5, 56.4, 29.5, 28.1 ppm; LCMS: m/z 424.0 (M+), Anal. Cald for C24H19N5O3: C,67.76;H,4.50;N,16.46;O,11.28; Found: C,67.80;H,4.60;N,16.53.

2.5.4

2.5.4 6-Amino-4-(4-chlorophenyl)-1-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylideneamino)-2-oxo-1,2-dihydropyridine-3,5-dicarbonitrile (4c)

Light Yellow powder, Yield: 350 mg (42%), mp 225–229 °C, 1H NMR (400 MHz, DMSO-d6) δ ppm = 10.08 (s, 2 H, NH2), 8.01–7.99 (d, 1H, ArH), 7.38–7.35 (d, 1H, ArH), 7.05 (s, 1H, ArH), 6.83 (s, 1H, ArH), 3.92 (s, 6 H, 2OCH3), 3.10–3.07 (t, 2 H, indane CH2), 2.66–2.64 (t, 2 H, indane CH2) ppm; 13C NMR (40 MHz, DMSO-d6) δ ppm = 165.6, 160.4, 155.0, 151.1, 150.3, 142.4, 134.7, 132.1, 130.6, 128.9, 127.9, 117.1, 110.1, 106.8, 92.3, 72.3, 56.5, 56.4, 29.5, 28.1 ppm; LCMS: m/z 460.9 (M+), Anal. Cald for C24H18ClN5O3:C,62.68;H,3.95;Cl,7.71;N,15.23;O,10.44; Found: C,62.90;H,3.89;N,15.28.

2.5.5

2.5.5 6-Amino-4-(3-bromophenyl)-1-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylideneamino)-2-oxo-1,2-dihydropyridine-3,5-dicarbonitrile (4d)

Yellow powder, Yield: 520 mg (65%), mp 255–259 °C, 1H NMR (400 MHz, DMSO-d6) δ ppm = 9.98 (s, 2 H, NH2), 8.39 (s, 1H, ArH), 7.85–7.83 (d, 1H, ArH), 7.69 (d, 1H, ArH), 7.32–7.28 (t, 1H, ArH), 7.05 (s, 1H, ArH), 6.84 (s, 1H, ArH), 3.92 (s, 6 H, 2OCH3), 3.10–3.07 (t, 2 H, indane CH2), 2.66–2.62 (t, 2 H, indane CH2) ppm; 13C NMR (40 MHz, DMSO-d6) δ ppm = 165.8, 160.4, 154.8, 152.0, 148.5, 142.4, 135.9, 133.0, 130.8, 128.9, 123.5, 117.2, 110.1, 106.8, 92.2, 69.0, 56.5, 56.4, 29.5, 28.1 ppm; LCMS: m/z 504.99 M+), Anal. Cald for C24H18BrN5O3: C,57.16;H,3.60;Br,15.84;N,13.89;O,9.52; Found: C,57.89;H,3.90;N,13.76.

2.5.6

2.5.6 6-Amino-1-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylideneamino)-4-(3-methoxyphenyl)-2-oxo-1,2-dihydropyridine-3,5-dicarbonitrile (4e)

Grey powder, Yield: 750 mg (90%), mp 245–248 °C, 1H NMR (400 MHz, DMSO-d6) δ ppm = 10.09 (s, 2 H, NH2), 7.71 (d, 1H, ArH), 7.59 (t, 1H, ArH), 7.55 (s, 1H, ArH), 7.04 (s, 1H, ArH), 6.94–6.91 (d, 1H, ArH), 6.83 (s, 1H, ArH), 3.92 (s, 6 H, 2OCH3), 3.78 (s, 3 H, OCH3), 3.10–3.07 (t, 2 H, indane CH2), 2.65 (t, 2 H, indane CH2) ppm; 13C NMR (40 MHz, DMSO-d6) δ ppm = 160.4, 158.1, 155.0, 151.2, 150.3, 148.5, 142.4, 134.6, 128.9, 127.6, 119.4, 117.9, 116.3, 110.1, 106.8, 92.0, 72.5, 56.5, 56.4, 54.9, 29.5, 28.1 ppm; LCMS: m/z 456.20 (M+), Anal. Cald for C25H21N5O4:C,65.93;H,4.65;N,15.38;O,14.05; Found: C,65.98;H,4.71;N,15.45.

2.5.7

2.5.7 6-Amino-1-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylideneamino)-4-(4-hydroxy-3-methoxyphenyl)-2-oxo-1,2-dihydropyridine-3,5-dicarbonitrile (4f)

Off White powder, Yield: 515 mg (60%), mp 205–215 °C, 1H NMR (400 MHz, DMSO-d6) δ ppm = 10.09 (s, 2 H, NH2), 7.79–7.76 (d, 1H, ArH), 7.49 (s, 1H, ArH), 7.13 (d, 1H, ArH), 7.05 (s, 1H, ArH), 6.84 (s, 1H, ArH), 6.46 (s, 1H, OH), 3.92 (s, 6 H, 2OCH3), 3.10–3.07 (t, 2 H, indane CH2), 2.66–2.62 (t, 2 H, indane CH2) ppm; 13C NMR (40 MHz, DMSO-d6) δ ppm = 160.4, 155.0, 154.4, 148.5, 146.7, 142.4, 128.9, 126.7, 121.1, 117.2, 113.6, 111.5, 110.1, 91.1, 72.9, 56.5, 56.4, 56.3, 29.5, 28.1 ppm; LCMS: m/z 472.20 (M+), Anal. Cald for C25H21N5O5: C,63.69;H,4.49;N,14.85;O,16.97; Found: C,64.01;H,4.59;N,14.95.

2.5.8

2.5.8 6-Amino-1-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylideneamino)-4-(3-fluorophenyl)-2-oxo-1,2-dihydropyridine-3,5-dicarbonitrile (4g)

Off white powder, Yield: 280 mg (35%), mp 220–225 °C, 1H NMR (400 MHz, DMSO-d6) δ ppm = 10.07 (s, 2 H, NH2)7.90–7.87 (d, 1H, ArH), 7.81–7.78 (s, 1H, ArH), 7.65–7.59 (t, 1H, ArH), 7.23–7.18 (d, 1H, ArH), 7.05 (s, 1H, ArH), 6.83 (s, 1H, ArH), 3.92 (s, 6 H, 2OCH3), 3.10–3.07 (t, 2 H, indane CH2), 2.66–2.62 (t, 2 H, indane CH2) ppm; 13C NMR (40 MHz, DMSO-d6) δ ppm = 264.4, 160.4, 155.6, 155.5, 151.5, 148.5, 142.4, 135.3, 129.0, 128.9, 121.2, 120.9, 116.1, 110.1, 106.8, 92.1, 72.2, 56.5, 56.4, 29.5, 28.1 ppm; LCMS: m/z 444.0 (M+), Anal. Cald for C24H18FN5O3: C,65.01;H,4.09;F,4.28;N,15.79;O,10.82; Found: C,65.08;H,4.15;N,15.90.

2.5.9

2.5.9 6-Amino-4-(3-chlorophenyl)-1-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylideneamino)-2-oxo-1,2-dihydropyridine-3,5-dicarbonitrile (4h)

Grey powder, Yield: 480 mg (57%), mp 228–230 °C, 1H NMR (400 MHz, DMSO-d6) δ ppm = 10.3 (s, 2 H, NH2), 8.28 (s, 1H, ArH), 8.09–8.06 (d, 1H, ArH), 7.38–7.35 (d, 1H, ArH), 7.32–7.29 (t, 1H, ArH), 7.04 (s, 1H, ArH), 6.84 (s, 1H, ArH), 3.92 (s, 6 H, 2OCH3), 3.10–3.07 (t, 2 H, indane CH2), 2.66–2.62 (t, 2 H, indane CH2) ppm; 13C NMR (40 MHz, DMSO-d6) δ ppm = 164.7, 160.4, 154.9, 150.7, 150.3, 148.5, 142.4, 134.0, 130.3, 129.9, 129.1, 128.9, 116.8, 113.4, 110.1, 106.8, 91.4, 69.7, 56.5, 56.4, 29.5, 28.1 ppm; LCMS: m/z 460.80 (M+), Anal. Cald for C24H18ClN5O3: C,62.68;H,3.95;Cl,7.71;N,15.23;O,10.44; Found: C,62.89;H,3.85;N,15.29.

2.5.10

2.5.10 6-Amino-1-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylideneamino)-4-(2-methoxyphenyl)-2-oxo-1,2-dihydropyridine-3,5-dicarbonitrile (4i)

Grey powder, Yield: 360 mg (43%), mp 216–220 °C, 1H NMR (400 MHz, DMSO-d6) δ ppm = 10.5 (s, 2 H, NH2), 7.90–7.87 (d, 1H, ArH), 7.38–7.34 (t, 1H, ArH), 7.27–7.22 (t, 1H, ArH), 7.05 (s, 1H, ArH), 6.93–6.91 (d, 1H, ArH), 6.83 (s, 1H, ArH), 3.92 (s, 6 H, 2OCH3), 3.85 (s, 3 H, 2OCH3), 3.10–3.07 (t, 2 H, indane CH2), 2.66–2.62 (t, 2 H, indane CH2) ppm; 13C NMR (40 MHz, DMSO-d6) δ ppm = 163.7, 160.4, 157.4, 150.9, 150.3, 148.5, 142.4, 132.6, 129.6, 128.9, 128.2, 119.4, 117.2, 110.1, 106.8, 81.7, 70.8, 56.5, 56.4, 55.6, 29.5, 28.1 ppm; LCMS: m/z 456.80 (M+), Anal. Cald for C25H21N5O4: C,65.93;H,4.65;N,15.38;O,14.05; Found: C,66.05;H,4.70;N,15.44.

2.5.11

2.5.11 6-Amino-1-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylideneamino)-4-(3-nitrophenyl)-2-oxo-1,2-dihydropyridine-3,5-dicarbonitrile (4j)

Grey powder, Yield: 480 mg (56%), mp 224–228 °C, 1H NMR (400 MHz, DMSO-d6) δ ppm = 10.7 (s, 2 H, NH2), 8.94 (s, 1H, ArH), 8.38–8.36 (d, 1H, ArH), 8.24 (d, 1H, ArH), 7.64–7.60 (t, 1H, ArH), 7.04 (s, 1H, ArH), 6.84 (s, 1H, ArH), 3.92 (s, 6 H, 2OCH3), 3.07 (t, 2 H, indane CH2), 2.66–2.62 (t, 2 H, indane CH2) ppm; 13C NMR (40 MHz, DMSO-d6) δ ppm = 167.2, 160.4, 154.8, 151.7, 148.5, 146.0, 142.4, 134.7, 131.0, 130.7, 127.1, 125.3, 118.1, 114.6, 110.1, 106.8, 91.29, 71.52, 56.5, 56.4, 29.5, 28.1 ppm; LCMS: m/z 469.00 (M+), Anal. Cald for C24H18N6O5:C,61.27;H,3.86;N,17.86;O,17.00; Found: C,61.58;H,3.95;N,17.98.

2.5.12

2.5.12 6-Amino-1-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylideneamino)-4-(2-ethoxyphenyl)-2-oxo-1,2-dihydropyridine-3,5-dicarbonitrile (4k)

Off White powder, Yield: 430 mg (50%), mp 226-229 °C, 1H NMR (400 MHz, DMSO-d6) δ ppm = 10.7 (s, 2 H, NH2), 7.96–7.94 (d, 1H, ArH), 7.38–7.34 (t, 1H, ArH), 7.26–7.22 (t, 1H, ArH), 7.05 (s, 1H, ArH), 6.84 (s, 1H, ArH), 6.77 (d, 1H, ArH), 4.18–4.13 (m, 2 H, CH2), 3.92 (s, 6 H, 2OCH3), 3.10–3.07 (t, 2 H, indane CH2), 2.65–2.62 (t, 2 H, indane CH2), 1.40–1.37 (t, 3 H, CH3) ppm; 13C NMR (40 MHz, DMSO-d6) δ ppm = 164.7, 160.4, 154.9, 150.7, 150.3, 148.5,142.4, 135.3, 129.0, 128.9, 121.2, 120.9,118.1, 114.6, 110.1, 106.8, 91.29, 71.52, 56.5, 56.4, 29.5, 28.1 ppm; LCMS: m/z 469.00 (M+), Anal. Cald for C26H23N5O4: C,66.51;H,4.94;N,14.92;O,13.63; Found: C,66.81;H,4.85;N;14.80.

2.6

2.6 Antimicrobial activity

The in vitro antimicrobial activity of the compounds 4(a–k) was studied by disc agar diffusion technique at different concentrations of 50 mg/ml using Dimethylformamide as solvent. The specific bacterial culture was spread uniformly over nutrient agar in Petri plates. Then the test solution, standard and control of known similar concentrations were spotted in sample wells at specific distances. The zones of inhibition were measured after 24 h. The in vitro antibacterial activity was performed against Gram-positive bacteria including Staphylococcus aureus (MTCC 96), Streptococcus pyogenes (MTCC 442) and Gram negative bacteria including Escherichia coli (MTCC 443), Pseudomonas aeruginosa (MTCC 424). Yeast including Candida albicans (MTCC 227) and fungi Aspergillus clavatus (MTCC 1323) were used to test antifungal activity. Known antibiotics like Ampicilline and Chloramphenicol (the reference anti bacterial drugs) and Fluconazole (the reference antifungal drug) were used for comparison. The antimicrobial activities are summarized in Table 1.

Table 1 Antibacterial and Antifungal activity of novel compounds at concentration 50 mg/ml in DMF (4a–k).
Compound no. Zone diameter of growth inhibition in mm
Antibacterial activity Antifungal activity
Gram +ve Gram −ve C. albicans A. clavatus
S. aureus S. pyogenes E. coli P. aeruginosa
4a 14 14 16 14 18 20
4b 11 15 15 14 20 21
4c 19 18 17 14 20 23
4d 20 15 14 11 20 18
4e 10 14 14 14 21 16
4f 13 15 15 12 17 13
4g 12 17 16 13 19 18
4h 15 14 14 11 20 23
4i 21 14 17 14 23 19
4j 11 16 17 13 21 18
4k 12 15 22 13 20 23
Ampicilline 18 19 20 20 – –
Chloramphenicol 21 20 23 21 – –
Fluconazole – – – – 24 24

Bold figures indicates better or equivalent activity compared to existing drugs.

3

3 Result and discussion

A series of 6-amino-1-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylideneamino)-2-oxo-4-aryl-1,2-dihydropyridine-3,5-dicarbonitrile derivatives 4(a–k) was prepared from the reaction of 2-Cyano-N′-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylidene) aceto-hydrazide with 2-arylidenemalononitrile in the presence of a catalytic amount piperidine to provide the title compounds. The purity of compounds was analysed by TLC. The structures of all compounds were confirmed by 1H-NMR, 13C-NMR, Mass analysis and Elemental analyses. The supporting information can be seen from the spectral data which confirm the formation of claimed compounds.

The antibacterial activity of newly synthesized compounds 4(a–k) was performed by the agar disc-diffusion method against Gram-positive bacteria S. aureus, S. pyogenes and Gram negative bacteria including E. coli, P. aeruginosa. Yeast including Candida albicans and fungi Aspergillus clavatus were used. Results are summarized in Table 1. Zone of inhibition was compared with the reference standard Ampicilline, Chloramphenicol (antibacterial agent) and Fluconazole (antifungal agent). From the result of antibacterial data, compounds 4c, 4d, 4i, 4k shows good activity as antibacterial agent while compounds 4c, 4h, 4i, 4j shows good activity as antifungal agent.

4

4 Conclusion

A series of novel 6-amino-1-(5,6-dimethoxy-2,3-dihydro-1H-inden-1-ylideneamino)-2-oxo-4-aryl-1,2-dihydropyridine-3,5-dicarbonitrile derivatives were designed and synthesized, and their structures were characterized by 1H NMR, mass spectroscopy and elemental analysis. The bacterial and fungicidal activities of the new compounds were evaluated. The results of preliminary bioassays indicate that a number of these molecules exhibit antibacterial activities against Gram-positive and Gram-negative bacteria as well as antifungal stains, which are comparable to commercially available drugs. The modification of the Pyridine ring of the parent compound offers a promising prospect and more active analogues are expected to be found.

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Appendix A

Supplementary data

Supplementary data associated with this article can be found, in the online version, at https://doi.org/10.1016/j.arabjc.2014.07.014.

Appendix A

Supplementary data

Supplementary data 1

Supplementary data 1


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