Synthesis Of 4-Ayridone Lab Report

Pat 1
Synthesis of 4-aryl-6-indolylpyridine-2-carbonitriles and evaluation of their biological activity
Synthesis of 6-indolyl-4-aryl-3-cyanopyridine-2-one (1a-e)
Employing the MCRs approach and microwave irradiation, an equimolar amounts of aromatic aldehyde, 3-acetylindole, ethyl cyanoacetate were reacted with excess of ammonium acetate in one-pot, reaction, under the microwave irradiation, afforded a novel series of 4-aryl-6-indolyl-nicotinonitrile-2-one derivatives 1a-e. Ethylene glycol was used as a solvent and piperidine was employed as a catalyst during the microwave syntheses at a power of 250 W and 150 oC for a (15-20) min, scheme 1. All compounds were characterized by IR, mass, and NMR spectroscopy. The rate of reactions, and
Its 1H-NMR (DMSO-d6) δ ppm spectrum (chart 6) revealed the presence of these signals at δ 3.8 (s, 3H, OCH3), 6.57 (s, 1H, H-5 pyridone), 7.08 (d, J = 8.4 Hz, 2H, aromatic), 7.18 (m, 2H, indolyl), 7.49 (d, J = 8.5 Hz, 1H, indolyl), 7.69 (d, J = 8.4 Hz, 2H, aromatic), 7.86 (d, J = 8.5 Hz, 1H, indolyl), 8.27 (d, 1H, indolyl), 12.06 (s, 1H, NH pyridone, D2O exchangeable), 12.35 (1H, d, NH indole, D2O exchangeable). The 13C-NMR (DMSO-d6) δ ppm (chart 7) revealed the existence of the following signals δ 108.82 (CN), 113.28, 114.81, 117.96, 120.09, 121.99, 123.33, 124.56, 129.13, 129.71, 129.88, 130.32, 137.35, 137.51, 147.59, 159.9, 161.47 (aromatic carbons), 162.43 (CO amide). The mass spectrum (chart 8) supported the structure of compound 1b, where the mass spectrum for 1a with the molecular formula C21H15N3O3 the molecular ion peak [M‏+] exactly at (m/z) = 341.00,
IC50 values of four selected compounds
Antimicrobial activity of compounds (3b, d and e)
Compounds (3b, d, and e), were investigated for their antimicrobial activity at concentration (2 mg/ mL) using DMSO (50% in water) as negative control by well diffusion method, against Bacillus subtilis, Staphylococcus aureus (gram positive), Escherichia coli (gram negative) and Candida (yeast). Each well in the agar plate was seeded by (100 µL) from each tested compound or (50% DMSO). The plates were incubated at 37°C for 24 hours. the inhibition zone around each well in mm were measured, table 3. strain 3b 3d 3e
Bacillus subtilis 2 4.3 3.3
Staphylococcus aureus - 3.67 3.67
Escherichia coli - - -
Candida 1.33 3.67 2.6
Table 3. The antimicrobial activity for compounds 3b, d, and e
As we can see compound 3b exhibited minor activity against the Bacillus subtilis and Staphylococcus (g. positive) aureus and Candida, meanwhile the activity of compound 3d and 3e showed mild activity. None of the three tested compounds showed any activity against the gram negative bacteria E. coli. Meaning that, their reactivity are selective to gram positive bacteria, and