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[Figure not available: see fulltext.] An efficient approach based on pyrone ring opening in 3-arylisocoumarins in the presence of cyclic secondary amines was developed in order to prepare amides of deoxybenzoin-2'-carboxylic acids, diverse functionalized structures useful for the synthesis of polyfunctional compounds. [ABSTRACT FROM AUTHOR]

[Figure not available: see fulltext.] A convenient sequence for the preparation of 2-(4-chlorophenyl)-1-(2,4-dimetoxyphenyl)-3-(dimethylamino)prop-2-en-1-one has been developed. It has been demonstrated that the use of 1-(2,4-dihydroxyphenyl)ethanone or 1-(2-hydroxy-4-methoxyphenyl)ethanone in a condensation reaction with N, N-dimethylformamide dimethyl acetal leads to their heterocyclization to give an isoflavone. Reactions of the enamino ketone with N, O- and N, N-binucleophiles have been studied; as the result, 4,5-diarylisoxazole, 4,5-diarylpyrazoles, and 4,5-diaryl-substituted 2-aminopyrimidine have been obtained in good yields. [ABSTRACT FROM AUTHOR]

(4-Cyanooxazol-5-ylamino)acetates and (4-cyanooxazol-5-ylamino)acetamides after treatment with trifluoroacetic acid undergo recyclization to the mixture of corresponding 5-aminooxazoles, 5-trifluoroacetylaminooxazoles, and oxazolopyrimidinones. The structures have been confirmed for certain products which have been isolated in pure form. [ABSTRACT FROM AUTHOR]

Series of new potent inhibitors of growth of Staphylococcus aureus Newman, based on 3,4-diphenylpyrazole and 4,5-diphenylisoxazole derivatives were discovered. Structures of interest were selectively modified to check their structure–activity relationship. Studies revealed the most essential groups in the molecule for the antimicrobial activity retention. Active compounds with good MIC range should contain both nonpolar aromatic residues and hydrogen bond donating groups. The best MIC results in selected cases were lower than 1 μg/ml. [ABSTRACT FROM AUTHOR]

The synthesis of new cyclopenta[4',5']pyrido[3',2':4,5]furo[3,2-d]pyrimidin-7-amines have been carried out to study their antimicrobial activity. The biological tests evidenced that some of the synthesized compounds exhibit pronounced antimicrobial properties. A study of the structure–activity relationship revealed that the 3,5-dimethyl-1H-pyrazol-1-yl moiety linked to the carbon C-9 of the pyrimidine plays a decisive role in the manifestation of activity. The influence of 3,5-dimethyl-1H-pyrazol-1-yl group on the Dimroth rearrangement and azide-tetrazole equilibrium has also been examined. [ABSTRACT FROM AUTHOR]

A series of 2,2-disubstituted 8-azachromanones, including spirocyclic compounds, have been synthesized via Horner–Wadsworth– Emmons reaction. Dimethyl methylphosphonate was acylated with methyl 2-methoxypyridine-3-carboxylate to afford the key intermediate – dimethyl [2-(2-methoxypyridin-3-yl)-2-oxoethyl]phosphonate. Further reaction of this phosphonate and ketones followed by treatment with TMSCl–NaI provided the target 8-azachromanones. Scope and limitations of the developed synthetic method have been investigated. [ABSTRACT FROM AUTHOR]

[Figure not available: see fulltext.] Hybrid compounds containing both flavanone and pyrazole moieties have been synthesized from acetylnaphthols and pyrazole-4-carbaldehydes in good yields using microwave irradiation in a one-step procedure. The synthesized compounds were evaluated for their anticancer activity against four human cancer cell lines. [ABSTRACT FROM AUTHOR]

Sulfur-and nitrogen-containing derivatives of spirodihydropyranochromen-2-ones at the exocyclic oxygen atom have been synthesized. Modification of the oximes and hydrazones of the spiro-substituted pyranocoumarins with N-substituted amino acids were carried out using activated ester and symmetrical anhydride methods. [ABSTRACT FROM AUTHOR]