• Journal of the Korean Chemical Society
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• v.52 no.3
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• pp.249-256
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• 2008

3-Acetyl/Formyl 4-hydroxy-2H(1)-benzopyran-2-one on treatment with malonitrile and ethyl cyanoacetate yielded 1,1-dicyano-2-[4/-hydroxy-2/H(1)-benzopyran-2/-one-3/-yl] ethene/propene 2a-h and ethyl-2-cyano-3-[4/-hydroxy-2/H (1)-benzopyran-2/-one-3/-yl] propenoate/butenoate 3a-h respectively. The 1,3 dipolar reaction of 2a-h with NaN3 gave the tetrazole derivative 4a-h. 3a-h on cyclization with PPA gave 3-cyano-2H,5H-pyrano [3, 2-c] benzopyran-2,5-diones 5a-h which on 1,3 dipolar reaction with NaN3 to gave 3-(1/H-tetrazol-5/-yl)-2H,5H-pyrano[3, 2-c] benzopyran-2,5-diones 6a-h. The structures of the compounds have been established on the basis of the spectral and analytical data. All the compounds were screened for their antimicrobial activities and have been found to exhibited significant antibacterial activities. Compounds 2h and 4h showed the activity 50g/mL.

• Journal of the Korean Chemical Society
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• v.47 no.2
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• pp.137-146
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• 2003

3-Hydroxybenzopyran[3,2-c]-[1]-benzopyran-6,7-diones (3) and 3-methoxycarbonylcoumarin (4) were prepared via condensation of 1 with resorcinol in the presence of sodium methoxide. The chemical behavior of 3 towards acetic anhydride, alkyl halides and diazonium chloride is described. The electron impact ionization mass spectra of compounds 4,5 and 6a,b show a weak molecular ion peak and a base peak of m/z 89, m/z 280. m/z 91 and m/z 120 resulting from a cleavage fragmentation respectively. The molecular ion of compounds 3, 6b, and 7a is a base peak of m/z 280, m/z 366 and m/z 488 respectively. Compound 7a give a characteristic fragmentation pattern with a two very stable fragmentation of m/z 383 and m/z 77.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1543-1546
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• 2011

N-Bromosaccharin/$Mg(ClO_4)_2$ is an effective and regioselective system for ${\alpha}$-monobromination of 1,3-dicarbonyl compounds. A wide variety of ${\beta}$-keto esters and 1,3-diketones in reaction with this system afforded a regioselectively ${\alpha}$-monobrominated products. The bromination reaction can be conducted at 0-5 $^{\circ}C$ either in solution or under solvent-free conditions.

• Journal of the Korean Chemical Society
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• v.40 no.7
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• pp.519-525
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• 1996

3-Carbomethoxy-1(3H)-isobenzofuranone(9) underwent condensation with ${\alpha}{\beta}-unsaturated$, esters 3a-b to produce the corresponding naphthacene-6,7-diones 11a-b with high yields in one pot procedure. Among the naphthacene-6,7-diones formed, compound 11a without an ethyl group at C-9 position was oxidized to give the naphthacene-5,12-dione 13a, while compound 11b containing the ethyl group was oxidized to give a 3:2 mixture of the naphthacene-5,7,12-trione 12b and naphthacene-5,12-dione 13b under the same experimental conditions.

• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.90-94
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• 2012

The furan-2-ylidene acetates (3a-d), obtained from the furan-2,3-diones (1a-b) and methyl/ethyl (triphenylphosphoranylidene)-acetates (2a-b), were converted via the Michael type reactions with 2,3-diaminopyridine and its derivatives (4a-c) into the corresponding pyrrol-2-ylidene-acetates (5a-j) in moderate yields (45-94%). Structures of these compounds were determined by the IR, NMR, elemental analysis, and X-ray diffraction method.

• Journal of Photoscience
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• v.12 no.2
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• pp.109-111
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• 2005

It was found that 1,4-diketones such as 1,4-diphenyl-l,4-butanediones containing N,N-dimethylaminophenyl (pDPB) and N,N-dimethylaminonaphthyl (nDPB) at C2 are converted into 3-(4-dimethylaminoaryl)-1-phenylpropan-lones (pPPA and nPPA) by treatment with $Ca(OH)_2$ in methanol, which was easily oxidized to enone, i.e., 3-(4-dimethylaminophenyl)-l-phenylpropenones (pPPE and nPPE), when treated with 2,3-dichloro-5,6-dicyano-l,4-benzoquinone (DDQ) in dichloromethane.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1521-1524
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• 2013

N-Propylsulfamic acid supported onto magnetic $Fe_3O_4$ nanoparticles (MNPs-PSA) was used as an efficient and magnetically recoverable catalyst for synthesis of 2H-Indazolo[2,1-b]phthalazine-1,6,11(13H)-trione derivatives from the three-component, one-pot condensation reaction of phthalhydrazide, aromatic aldehydes and cyclic 1,3-diones, in good to excellent yields at $100^{\circ}C$ under solvent-free conditions. The catalyst was easily separated with the assistance of an external magnetic field from the reaction mixture and reused for several consecutive runs without significant loss of its catalytic efficiency. In order to compare, the synthesis of 2H-Indazolo[ 2,1-b]phthalazine-1,6,11(13H)-trione derivatives in the presence of catalytic amount of sulfamic acid (SA) under same reaction condition was also reported.