• Bulletin of the Korean Chemical Society
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• v.31 no.3
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• pp.539-540
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• 2010

• Bulletin of the Korean Chemical Society
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• v.14 no.4
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• pp.465-468
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• 1993

Four compounds containing two 2,2,6,6-tetramethylpiperidin-1-yloxyl radicals were synthesized. They are all chemically bonded with squaric moieties. The diradical compounds show fundamentally the paramagnetic behaviors satisfying the theoretical magnetic susceptibility according to Curie's law. A diradical compound of salf-form 4 however shows a relatively strong antiferromagnetic interaction in comparison with other reported organic radicals. The antiferromagnetic interaction of diradical 4 approximates a value of J/k= -50 K by the theoretical analysis of its temperature dependence.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.6 no.2
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• pp.177-181
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• 2020

Dual-modality imaging strategy using near-infrared fluorescence (FLI) and photoacoustic imaging (PAI) demands a suitable probe to enable dual-modular signal production. Herein, we demonstrate a synthetic protocol of small molecular dye for dual-modular FLI and PAI. A condensation reaction between squaric acid and carboxypentyl benzoindolium, and followed by basic hydrolysis to give the benzoindole derived squaraine (BSQ) dye in 49% yield. Next, the carboxylic acid group of BSQ was further functionalized with N-hydroxysuccinimide or azide group for an efficient conjugation with a targeting biomolecule. BSQ showed a maximum fluorescent emission at around 680 nm and the photoacoustic signal reached a maximum intensity at 680-700 nm. Based on these results, we conclude that BSQ analogs will be useful probes for dual-modular (FLI/PAI) imaging studies in animal models.

• Textile Coloration and Finishing
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• v.26 no.3
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• pp.272-276
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• 2014

The functional materials have been developed as a promising research topic toward the end uses for organic materials and applications. In this study, fluorescein based dye was synthesized by three step reaction. We have designed and synthesized the colorimetric dye through the reactions of fluorescein and methoxy group and ethylene diamine and squaric acid. The structure of the non-fluorescent spirolactam was elucidated by $^1H$-NMR, LC-Mass and FT-IR analyzes. Further studies are in progress to understand the effects of various substituent during the recognition process and to develop fluorescein based sensors for cations or anions.

• Bulletin of the Korean Chemical Society
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• v.6 no.1
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• pp.33-36
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• 1985

The luminescence intensity of $Tb^{3+}$ bound to picolinic acid, squaric acid, and 2,3-pyrazinedicarboxylic acid has been studied in water and water-ethanol mixtures. It has been found that the emission intensity of $Tb^{3+}$ in the complexes is enhanced with the increase of ethanol content in water-ethanol mixtures. Several factors affecting on the emission intensity of $Tb^{3+}$ in waterethanol mixtures are discussed.

• Journal of Yeungnam Medical Science
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• v.23 no.2
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• pp.232-239
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• 2006

Treatments for alopecia areata include topical corticosteroid treatment, corticosteroid intralesional injection, systemic corticosteroid treatment, PUVA(psoralen-UVA) and topical immunotherapy. The therapeutic effects are variable. Alopecia totalis is hard to treat completely. Topical immunotherapy with dinitrochlorobenzene (DNCB), squaric acid dibutyl ester (SADBE) or diphenylcyclopropenone (diphencyprone, DPCP) represents the most accepted therapeutic modality for the treatment of extensive alopecia areata. We report two cases of alopecia totalis treated with DPCP. After DPCP treatment, total scalp hair was completely recovered.