Publications by authors named "Levon S Atabekyan"

The photoprocesses of diethylamino derivatives of 1,4- and 1,3-distyrylbenzenes in MeCN were studied using absorption, luminescence, H NMR, and laser kinetic spectroscopy. Compounds and undergo intersystem crossing to the triplet state and exhibit delayed fluorescence. It was concluded that dye radical anions and radical cations are formed upon dismutation of the triplet state in the presence of an electron donor or acceptor.

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Photoprocesses in 1,4-diazadistyrylbenzene () and 1,3-diazadistyrylbenzene derivative () diperchlorates in MeCN were studied by absorption, luminescence, and kinetic laser spectroscopies. For compound , -photoisomerization and intersystem crossing to a triplet state are observed. For compound , photoelectrocyclization is suggested.

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Amlodipine, a unique long-lasting calcium channel antagonist and antihypertensive drug, has weak fluorescence in aqueous solutions. In the current paper, we show that direct visualization of amlodipine in live cells is possible due to the enhanced emission in cellular environment. We examined the impact of pH, polarity and viscosity of the environment as well as protein binding on the spectral properties of amlodipine in vitro, and used quantum chemical calculations for assessing the mechanism of fluorescence quenching in aqueous solutions.

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Boron difluoride of 3-amino-1,3-diphenyl-2-propene-1-onate (1) has been synthesized and its crystal structure has been determined. The comparative studies of 1 and its oxygen analog 1,3-diphenyl-1,3-dionate (dibenzoylmethanate) of boron difluoride (2) have been performed using the methods of stationary and time-resolved spectroscopy and quantum chemical modeling. It was established that at the transition from solutions to crystals, a bathochromic shift of the spectra and a significant increase of luminescence intensity of 1 take place.

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