2941-62-0Relevant articles and documents
Synthesis and photochemical evaluation of iodinated squarylium cyanine dyes
Santos, Paulo F.,Reis, Lucinda V.,Duarte, Isabel,Serrano, Joao P.,Almeida, Paulo,Oliveira, Anabela S.,Ferreira, Luis F. Vieira
, p. 1135 - 1143 (2005)
Several (multiply) iodinated squarylium cyanine dyes of type 1 and 8 (see Scheme and Table), derived from 1,3-benzothiazole and 6-iodo-1,3-benzothiazole, were synthesized as potential new photosensitizers, with absorptions in the 700-nm region. Their ability to generate singlet oxygen (1O 2) was assessed by luminescence-decay measurement in the near-IR. Some of these new dyes show interesting photophysical properties, and may be potentially used in photodynamic therapy (PDT).
Synthesis and characterization of near-infrared absorbing water soluble squaraines and study of their photodynamic effects in DLA live cells
Shafeekh, Kulathinte M.,Soumya, Mohanannair S.,Rahim, Moochikkadavath A.,Abraham, Annie,Das, Suresh
, p. 585 - 595 (2014)
Here, we report the synthesis, photophysical properties and photodynamic effects in DLA live cells of three water soluble squaraine dyes, viz. bisbenzothiazolium squaraine dyes SQMI and SQDI with iodine in one and both benzothiazolium units, respectively, and an unsymmetrical squaraine dye ASQI containing iodinated benzothiazolium and aniline substituents. The diiodinated SQDI showed an anomalous trend in both fluorescence and triplet quantum yields over the monoiodinated SQMI, with SQDI showing higher fluorescence and lower triplet quantum yields compared to SQMI. Nanosecond laser flash photolysis of SQDI and SQMI indicated the formation of triplet excited states with quantum yield of 0.19 and 0.26, respectively. On photoirradiation, both the SQDI and SQMI generate singlet oxygen and it was observed that both dyes undergoing oxidation reactions with the singlet oxygen generated. ASQI which exhibited a lower triplet quantum yield of 0.06 was, however, stable and did not react with the singlet oxygen generated. In vitro cytotoxicity studies of these dyes in DLA live cells were performed using Trypan blue dye exclusion method and it reflect an order of cytotoxicity of SQDI>SQMI>ASQI. Intracellular generation of the ROS was confirmed by dichlorofluorescein assay after the in vitro PDT. Synthesis, photophysical properties and photodynamic effects in DLA live cells of three water soluble squaraine dyes, SQDI, SQMI and ASQI, are presented. On photoirradiation, both the SQDI and SQMI generate singlet oxygen where both the dyes undergoing oxidation reactions with the singlet oxygen generated, whereas ASQI was stable and did not react with the singlet oxygen. In vitro cytotoxicity studies of these dyes in DLA cells were performed using Trypan blue dye exclusion method and intracellular generation of ROS was confirmed using dichlorofluorescein assay after the in vitro PDT.
Design, synthesis and photophysical studies of styryl-based push-pull fluorophores with remarkable solvatofluorochromism
Safir Filho, Mauro,Fiorucci, Sebastien,Martin, Anthony R.,Benhida, Rachid
, p. 13760 - 13772 (2017)
A library of 20 styryl-based push-pull dyes derived from 6-amino substituted benzothiazoles were prepared by an efficient and practical synthetic route from low-cost starting materials. The dyes were firstly designed to present an effective anchoring site for subsequent conjugation. A series of aryl scaffolds, from substituted phenyl rings containing electron donating and withdrawing groups to polycyclic aromatic derivatives, were screened. The inductive effect of N-alkyl substituted benzothiazoles was also explored for three different arrangements. The investigation of the structure-photophysics relationship was performed by UV-vis absorption and steady-state fluorescence emission measurements in solution and by TD-DFT calculations. The dyes presented high brightness, absorption bands in the visible range (～370-453 nm) and large solvatofluorochromism comprising all the visible spectrum, as a consequence of the strong intramolecular charge transfer (ICT) nature of their excited state.
Synthesis of 6-aminobenzothiazoles from p-benzoquinone imine derivatives
Manning,Horak
, p. 363 - 365 (1978)
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Nickel-Catalyzed Cross-Coupling of Ammonia or Primary Alkylamines with (Hetero)aryl Sulfamates, Carbamates, or Pivalates
MacQueen, Preston M.,Stradiotto, Mark
supporting information, p. 1652 - 1656 (2017/08/11)
A catalyst system capable of effecting the cross-coupling of ammonia or primary alkylamines with (hetero)aryl sulfamates, carbamates, or pivalates is reported for the first time. The air-stable nickel(II) pre-catalyst C1 tolerates a broad spectrum of heterocyclic functionality within both reaction partners, as well as ether, nitrile, pyrrole, trifluoromethyl, and boronate ester substituents. In the case of reactions involving primary alkylamines and (hetero)aryl sulfamates and carbamates, room-temperature cross-couplings were achieved.
