207986-25-2Relevant articles and documents
Nucleus-independent chemical shift (NICS) as a criterion for the design of new antifungal benzofuranones
González-Chávez, Marco Martín,González-Chávez, Rodolfo,Méndez, Francisco,Martínez, Roberto,Ni?o-Moreno, Perla Del Carmen,Ojeda-Fuentes, Luis Enrique,Richaud, Arlette,Zerme?o-Macías, María de los ángeles
, (2021/08/30)
The assertion made by Wu et al. that aromaticity may have considerable implications for molecular design motivated us to use nucleus-independent chemical shifts (NICS) as an aromaticity criterion to evaluate the antifungal activity of two series of indol-4-ones. A linear regression analysis of NICS and antifungal activity showed that both tested variables were significantly related (p –1 for Candida glabrata, Candida krusei and Candida guilliermondii with compounds 15-32, 15-15 and 15-1. The MIC for filamentous fungi was 1.95 μg·mL–1 for Aspergillus niger for compounds 15-1, 15-33 and 15-34. The results obtained support the use of NICS in the molecular design of compounds with antifungal activity.
Diarylamino groups as photostable auxofluors in 2-benzoxazolylfluorene, 2,5-diphenyloxazoles, 1,3,5-hexatrienes, 1,4-distyrylbenzenes, and 2,7-distyrylfluorenes
Kauffman, Joel M.,Moyna, Guillermo
, p. 839 - 853 (2007/10/03)
The relationship of structure to optical spectral properties was determined for five types of fluors in a search for an optimum-wavelength shifter to be used as part of the detection systems for high-energy particles from accelerators. In a search for photostable fluors to serve as waveshifters in plastic fibers it was found that the wavelengths of interest, absorption max 410 ± 10 nm and fluorescence emission max 480 ± 20 nm, along with other properties, such as high solubility and short fluorescence decay time, could be obtained from fluorophors composed of aromatic rings and vinyl groups only by using amino groups as auxochromes to give bathochromic shifts of wavelengths. Since primary, monoalkyl, and dialkylamino groups were not sufficiently photostable, a number of fluorophores bearing diarylamino groups were investigated. Syntheses of the fluors made use of the Buchwald amination, an improved version of the Emmons-Horner reaction, and other common reactions. The fluor types were the following: a 2-benzoxazolyl-7-(4-diarylamino)fluorene 7, 2-(4-cyanophenyl)-5-(4-aminophenyl)oxazoles 14 and 20, 1,3,5-hexatrienes 24a-d and 26a-c, 1,4-distyrylbenzenes 31d-g and 32a-e, and 2,7-distyrylfluorenes 40a,d-e. The unsymmetrical fluors 7, 14, and 20 were not as bright as the best hexatrienes, distyrylbenzenes, and distyrylfluorenes, which were all symmetrical. Where the 1,6-diaryl-1,3,5-hexatrienes 24a-d had high fluorescence quantum yield (Φf), the 1,1,6,6-tetraryl-1,3,5-hexatrienes 26a-c had both lower ε and Φf. Where the 1,4-distyrylbenzenes 31d-g had high Φf, the 1,4-bis(2-phenylstyryl)benzenes 32a-e had (Φf = 0. Diarylamino groups as auxofluors conferred higher photochemical stability than dialkylamino groups on similar fluorophores. The 1,4-distyrylbenzenes 31d,e and the 2,7-distyrylfluorenes 40d,e had the most desirable properties overall, which included fast decay times of 2 ns. Computer simulations predicted absorption and emission wavelengths fairly well, but were of little help for the prediction of brightness, stability, Φf, or decay time.
