β-Aroylacrylic Acids

Abstract

The quest for new antibiotic substances produced by microorganisms has stimulated investigations on comparatively simple synthetic compounds, particularly those having structural features common to several of the natural antibiotics. Geiger and Conn2 have called attention to the structural feature, -CH=C-C=0 common to I both penicillic acid and clavacin and have postulated that the antibacterial activity of both compounds is very likely closely associated with this grouping. The fact that both clavacin, penicillic

<b>Synthesis of new &alpha;, &beta; -unsaturated butenolides</b>

“…The synthesis of β-(3-nitrobenzyol)acrylic acid (1a) and β-(4-methyl-3-nitrobenzyol)acrylic acid (1b) was carried out by a literature procedure [14]. The phenols (3a-f) (phenol, resorcinol, catechol, quinol, phloroglucinol and pyrogallol) were taken in slight excess over the acid (1).…”

Pyran and Pyridine as Building Blocks in Heterocyclic Synthesis

“…The β-aroylacrylic acid derivative 4-(4-chloro-3-methylphenyl)-4-oxo-but-2-enoic acid [29][30][31][32][33][34][35][36][37][38] (3) has interacted with malononitrile in dimethylformamide (DMF) in the presence of piperidine as a catalyst to afford-2-amino-6-(4-chloro-3-methylphenyl)-3-cyano-4H-pyran-4-carboxylic acid (4). On the other hand, when the reaction was carried out in the presence of ammonium acetate it yielded 2-amino-6-(4-chloro-3-methylphenyl)-3-cyanopyridine-4-carboxylic acid (5) (Scheme 1).…”

“…When compound (27) was allowed to react with acetylacetone in the presence of piperidine as catalyst it yielded 2-[4-acetyl-3-(carboxymethyl)-5-methylfuran-2-ylamino]-6-(4-chloro-3-methylphenyl)-3-cyanopyridine-4-carboxylic acid (29). The IR spectrum of (29) Refluxing compound (27) with malononitrile in the presence of ammonium acetate yielded 2-[5-amino-3-(carboxymethyl)-4-cyano-1H-pyrrol-2-ylamino]-6-(4-chloro-3-methylphenyl)-3-cyanopyridine-4-carboxylic acid (30).…”

“…A mixture of N-cyclic maleamic acid (27) (2.00 g, 5.19 mmol) and acetylacetone (0.53 mL, 5.19 mmol) in DMF (20 mL) in the presence of piperidine was refluxed at 60 o C for (3 h).The reaction mixture was allowed to cool at room temperature then poured into diluted solution of acetic acid (200 mL), the solid formed was filtered off, washed with water, dried and crystallized from ethanol/ water to afford furan derivatives (29).…”

Extrusion of Sulfur in the Reactions of Hydrazine Hydrate With 5-(2-Aryl-2-Oxoethylidene)-3-(2-Methoxy-Phenyl)-2-Thioxothiazolidin-4-Ones

“…The starting 5-[2-(4-bromophenyl)-2-oxoethyl]-3-(2-methoxyphenyl)-2-thioxothiazolidin-4-one 1b was synthesized from 3-(4-bromobenzoyl)-2-propenoic acid 4 and ammonium 2-methoxyphenyldithiocarbamate, following previously reported methods 5,6 . Treatment of 1b with bromine in acetic acid solution gave the respective 5-[2-(4-bromophenyl)-2-oxoethylidene] derivative 2b.…”