Synthesis, spectral characterization and bioactivity evaluation of novel α-aminophosphonates

<p>A facile synthesis of novel α-aminophosphonates <b>5a-j</b> was accomplished by condensation of imines (<b>3a-j)</b> with diethyl phosphite (<b>4</b>) in ethanol at 50–60°C using easily recoverable and reusable catalyst, tetramethyl guanidine (TMG) via pudovik reaction in high yields. All the title compounds were characterized by spectral and elemental analysis. They were further screened for their abilities towards <i>in vitro</i> antibacterial, antifungal and antioxidant activities. The compounds <b>5g</b>, <b>5d, 5f</b> exhibited good antibacterial and antifungal activities compared to the standard bactericide, Penicillin and fungicide, Griseofulvin, respectively. The compounds <b>5h</b>, <b>5i</b>, <b>5g</b>, and <b>5c</b> exhibited good antioxidant activity compared to the standard ascorbic acid.</p

Synthesis and bioactivity evaluation of some novel sulfonamide derivatives

<p>A simple and convenient method for the synthesis of biologically active sulfonamide derivatives was achieved. All the title compounds were characterized by spectral and elemental analysis. They were further screened in vitro for their abilities towards antibacterial, antifungal and antioxidant activities. The compound <i>N,N'</i>-(3,3′-dimethoxybiphenyl-4,4′-diyl)bis(4-fluorobenzenesulfonamide) (<b>5b</b>) and <i>N</i>-(3-(9H-carbazol-4-yloxy)-2-hydroxypropyl)-4-fluoro-N-isopropylbenzenesulfonamide (<b>5e</b>) exhibited good activity when compared to the standard bactericide, Chloramphenicol and fungicide, Ketoconazole respectively. The compounds (2S)-<i>N</i>-((2S,4S)-5-(4-Chloro-phenylsulfonamido)-4-hydroxy-1, 6-diphenylhexan-2-yl)-3-methyl-2-(2-oxotetrahydropyrim-idin-1(2H)-yl)butan-amide (<b>4f</b>) and (2S)-<i>N</i>-((2S,4S)-5-(4-fluorophenylsulfonamido)-4-hydroxy-1,6-diphenyl-hexan-2-yl)-3-methyl-2-(2-oxotetrahydropyrimidin-1(2H)-yl)bu-tana-mide (<b>5f</b>) exhibited good antioxidant activity when compared with standard antioxidant, Ascorbic acid.</p

Synthesis and bioactivity evaluation of new phenyl <i>N,N′-</i>phenylphosphorodiamidates

<p></p> <p>A series of new biologically active phenyl N,N<b>^′-</b>phenyl phosphorodiamidates were synthesized by reacting phenyl phenylphosphoramidochoridate with various amines. All the newly synthesized compounds <b>3a-j</b> were tested for their antioxidant activity by 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydrogen peroxide (H₂O₂) and nitric oxide (NO) methods. In all the three methods the compounds <b>3c</b> (phenyl N-(6-methoxy-1,3-benzothiazol-2-yl)-N′-phenyl-phosphorodiamidate) and <b>3e</b> (phenyl N-(5-ethyl-1,3,4-thiadiazol-2-yl)-N′-phenylphosphorodiamidate) showed good radical scavenging activity.</p