RESUMO
A class of aryl trifluoromethyl-containing beta-diketones were synthesized via one step Claisen condensation. These pi-conjugated diketones exhibit strong solvatochromism from intramolecular donor-acceptor charge transfer (CT). In addition, fluorescence quantum yields (phi(f)) and lifetimes (tau(f)) were measured in different solvents. Diketones exhibit bathochromic shifts in emission spectra with increasing solvent polarity. Fluorescence changes upon Group II metal binding were also studied. Despite the relatively simple structure, the anthracene-CF(3) diketone, atm, has strong binding affinity for Mg2+. A 70 nm blue shift and sixfold increase in intensity were observed upon addition of only one equivalent MgCl2 in ethanol solution. It also shows selectivity for Mg2+ binding even in the presence of excess Ca2+. Association constant (Ka) calculations suggest atm has two orders of magnitude stronger chelation for divalent magnesium than for calcium. These findings make atm an attractive starting point for molecular probe and light emitting material design.
Assuntos
Cálcio/química , Cetonas/química , Luminescência , Magnésio/química , Acetatos/química , Acetonitrilas/química , Etanol/química , Furanos/química , Cetonas/síntese química , Cloreto de Metileno/química , Fotoquímica , Teoria Quântica , Solventes/química , Espectrometria de Fluorescência , Tolueno/químicaRESUMO
Basal cell nevus syndrome (BCNS), or Gorlin Syndrome, is an autosomal dominant disorder, characterized by multiple developmental abnormalities and associated with germline mutations in the PTCH gene. Patients show multiple and early onset basal cell carcinomas (BCCs) in skin, odontogeniccysts in the jaw, pits on palms and soles, medulloblastoma, hypertelorism, and calcification of the falx cerebri. Clinical features of BCCs in these patients are indistinguishable from ordinary BCCs. However, some patients show variable histologic findings in subtypes of BCCs, and only one case associated with several histologic types of BCCs in the syndrome has been reported in Korea. We present a case of BCNS characterized by multiple BCCs, odontogenic keratocysts, multiple palmar pits, and calcified falx cerebri. Histopathologic findings of BCCs showed several patterns, which were nodular, superficial, and pigmented types.