74888-10-1Relevant articles and documents
Tuning of photoluminescence properties of functional phthalides for OLED applications
Shanmugasundaram, Madhesh,Joseph, Joshy,Ramaiah, Danaboyina
, p. 156 - 162 (2016)
With an objective to develop simple organic systems and tailor their properties for optoelectronic applications, we have synthesized three functionalized phthalide derivatives and have investigated their electroluminescence and photophysical properties under different conditions. These derivatives showed good solubility in common organic solvents and exhibited strong absorption in the range 320–400?nm, having molar extinction coefficient values of ca. 104?M?1?cm?1. The monomeric solution of these derivatives exhibited very low fluorescence quantum yields (ΦF) of ca. 0.003–0.04 owing to their inherent structural features such as intramolecular free rotation and decay to the dark triplet states. However, upon complexation with Lewis acids, such as BCl3, these derivatives showed increased fluorescence quantum yields up to ca. 0.21?±?0.01 and also exhibited aggregation induced emission (AIE) in water/acetonitrile mixtures with the emission yields in the range ca. 0.11–0.16. The morphological analysis of the aggregates through SEM and TEM showed the formation of rod-like structures in 90% water/acetonitrile mixture with an average size of ca. 100?nm. Supporting the observed aggregation induced enhancement in emission properties, these derivatives also exhibited significantly enhanced solid state fluorescence quantum yields of ca. 0.58–0.60. As a representative example, organic light emitting diode (OLED) fabricated using the derivative 3 as the emissive layer showed an efficient electroluminescence centered at 524?nm with a turn on voltage of 9?V, demonstrating thereby their potential use in optoelectronic applications.
Novel antiasthmatic agents with dual activities of thromboxane A2 synthetase inhibition and bronchodilation. 1. 2-[2-(1-imidazolyl)alkyl]- 1(2H)-phthalazinones
Yamaguchi,Kamei,Koga,Akima,Kuroki,Ohi
, p. 4052 - 4060 (2007/10/02)
A number of 4-substituted 2-[ω-(1-imidazolyl)alkyl]-1(2H)-phthalazinones were synthesized in order to develop agents possessing both thromboxane A2 synthetase inhibitory and bronchodilatory activities. The pharmacological evaluation of these compounds disclosed that they have both activities to various extents. Both activities were slightly dependent on the length of the 2-substituents and largely affected by the nature of the 4-substituents. Compounds bearing phenyl and thienyl groups exhibited relatively high and well-rounded activities. Among these compounds, 12j and 15f were found to be the most effective agents having well-rounded activities in vitro and in vivo. Introduction of a carboxyl group reduced both activities contrary to our expectation. 4-(3-Pyridyl)phthalazinone 18b was of particular interest because of unexpectedly high in vivo activities in spite of an absence of significant in vitro activities.
