10.1155/2012/767941
The research focuses on the synthesis, characterization, and antimicrobial studies of a new Mannich base, N-[morpholino(phenyl)methyl]acetamide (MBA), and its metal complexes with cobalt(II), nickel(II), and copper(II). The ligand MBA was synthesized using acetamide, benzaldehyde, and morpholine, and characterized by spectral studies including IR, UV-Visible, NMR, and mass spectrometry. The metal chelates were prepared by reacting MBA with metal salts, and further characterized by elemental analysis, IR, UV spectral studies, and magnetic moment measurements. The antimicrobial activities of MBA and its complexes were evaluated against various bacterial and fungal species using the disc diffusion method. The study found that the Co(II) nitrato complex exhibited the highest activity, suggesting that chelation enhances the antimicrobial properties of the ligand.
10.1021/jo00021a014
The research focuses on the modification of the Bischler-Napieralski reaction for the synthesis of 3-aryl-3,4-dihydroisoquinolines. The purpose of this study was to address the inefficiencies of the traditional Bischler-Napieralski reaction in synthesizing 3-arylisoquinolines, which are important intermediates for the synthesis of various isoquinoline alkaloids and potential medicinal agents. The researchers successfully developed a method that avoids the elimination of the amide group as a nitrile via the retro-Ritter reaction by converting it to an N-acyliminium intermediate with oxalyl chloride-FeCl3. This modification resulted in the formation of 3,4-dihydroisoquinolines in moderate to high yields. The chemicals used in the process include (1,2-diphenylethyl)amides, oxalyl chloride, FeCl3, and various amide derivatives such as formamide, acetamide, benzamide, and phenylacetamide. The study concluded that this new method offers a highly effective synthetic route for the asymmetric synthesis of natural products and medicinal agents containing the 3-arylisoquinoline ring system and provides an alternative, mild method for the preparation of simple 3,4-dihydroisoquinolines.
10.1080/00397910902985465
The research focuses on the facile and simple synthesis of novel 1-methyl-2-(2-substituted-oxazol-4-yl)-1H-benzimidazole derivatives, which are heterocyclic compounds with significant biological activity. The synthesis process involves the condensation of o-phenylenediamine with lactic acid to yield 2-(a-hydroxyethyl)benzimidazole, followed by oxidation to produce 2-acetyl benzimidazole. This compound undergoes N-methylation and bromination to form an intermediate, which is then converted into its ester form by reacting with various carboxylic acids in an acetone medium. The key step involves treating these esters with acetamide in the presence of BF3-etherate, a Lewis acid, to obtain the desired oxazole derivatives. The experiments utilized various analytical techniques, including 1H and 13C NMR, IR spectroscopy, mass spectrometry, and thin-layer chromatography (TLC), to monitor the progress of the reactions and characterize the synthesized compounds. The study successfully developed a facile synthetic process for the target benzimidazole derivatives and proposed a plausible mechanism for the conversion of esters to the corresponding oxazoles.
10.1002/hc.10106
The study focuses on the synthesis and chemical behavior of 5-chloro-1,2,4-thiadiazol-2-ium chlorides (salts 3), which are useful precursors to a variety of 6aλ4-thiapentalene systems. These salts were obtained by treating formimidoyl isothiocyanates (1) with an excess of methanesulfenyl chloride. The salts exhibited interesting chemical behavior towards several nitrogen and carbon nucleophiles, leading to the formation of diverse polyheterapentalene systems. Key chemicals used in the study include isothioureas, acetamide, p-toluidine, phenyl isothiocyanate, and active methylene compounds like methyl cyanoacetate and dimethyl malonate. These reagents served to displace the 5-chlorine atom of the salts, leading to the formation of various heterocyclic compounds such as 1H,6H-6aλ4-thia-1,3,4,6-tetraazapentalenes (7), 6H-6aλ4-thia-1-oxa-3,4,6-triazapentalene (9), and other thiapentalene derivatives. The study utilized IR and NMR spectroscopic data for structural assignments and received additional support from X-ray analysis of substrate 16a. The purpose of these chemicals was to explore the reactivity of the thiadiazolium salts and to synthesize new hypervalent sulfur compounds through nucleophilic substitution reactions.
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