The main mol-ecule of the title compound, C(2)H(8)N(+)·C(25)H(31)O(5) (-)·C(25)H(32)O(5)·0.5C(6)H(14)·H(2)O, exists as two crystallographically independent mol-ecules, the hydr-oxy group of one being deprotonated. The pyran rings of both independent units adopt boat conformations. One of the two cyclo-hexene rings of the xanthene unit adopts an envelope conformation whereas the other is in a ha...

We present the synthesis and characterization of a family regioisomerically pure pH-sensitive rosamine fluorophores consisting xanthene fluorophore cores differently substituted phenol moieties.

In order to study the structure-activity relationships of xanthene derivatives, four series of N-substituted 14-aryl-14H-dibenzo[a,j]xanthene-3,11-dicarboxamide derivatives were synthesized. The structures of all compounds were identified by ¹H-NMR, HR-MS and IR spectra, in which compounds 6a-h were further identified by 13C-NMR spectra. The in vitro antitumor activity of the synthesized compou...

The presentation of two phenols on a xanthene backbone is akin to the tyrosine dyad (Y730 and Y731) of ribonucleotide reductase. X-ray crystallography reveals that the two phenol moieties are cofacially disposed at 4.35 Å. Cyclic voltammetry reveals that phenol oxidation is modulated within the dyad, which exhibits a splitting of one-electron waves with the second oxidation of the phenol dyad o...

New naphtho[2,1,8,7-klmn]xanthene and benzo[kl]xanthene-based intramolecular phosphane–borane frustrated Lewis pairs (FLPs) were investigated in catalyzed H2 activation CO2 hydrogenation processes. According to DFT predictions at the B3LYP-D3 level, presence of rigid scaffolds increased P···B distances FLPs lead a remarkable drop energy barrier for (by up 19.2 kcal mol−1, compared parent dimeth...

To control the molecular organization of octadecyl rhodamine B (RhB18), hybrid Langmuir–Blodgett monolayers containing clay minerals were prepared. The orientation and conformation of the RhB18 molecule were analyzed by polarized attenuated total reflection Fourier transform infrared (ATR–FTIR) spectroscopy and fluorescence spectroscopy. Monomers and dimers of RhB18 were observed by UV-Vis abso...

A synthetic strategy for the construction of chiral salen ligands bearing two rigid xanthene spacers functionalized with carboxylic acid and ester groups is presented. Suzuki cross-coupling methodology is used to furnish the appropriately functionalized xanthene spacers to a salicylaldehyde, which is subsequently condensed with (1R,2R)-(-)-1,2-diaminocyclohexane to produce salen ligands featuri...

A new bis(N2O2) ligand, L(4-), in which two tripodal diamine-bis(phenolate) moieties are bridged by a xanthene backbone, was prepared. The reaction of H4L with 2 equiv. of [Ti(O(i)Pr)4] produced C2 and Cs symmetrical isomers of the dititanium(IV,IV) complex [Ti2(L)(O(i)Pr)4]. The isolated C2 isomer was slowly converted to the Cs isomer via Ti-N bond cleavage to form a 3 : 2 mixture in equilibri...

A practical and green method for the synthesis of 5H-dibenzo[b,i]xanthene-tetraones and spiro[dibenzo[b,i]xanthene-13,3'-indoline]-pentaones by the condensation of 2-hydroxynaphthalene-1,4-dione with aldehydes or isatins, respectively, in the presence of a catalytic amount of cellulose sulfuric acid (CSA) under solvent-free conditions at 100 °C is described. The significant features of this pro...

Addition of a single functional handle to the tricyclic moiety of fluorescein results in asymmetric xanthene dyes. Our synthesis of a new class of asymmetric xanthenes proceeds via an unusual SNAr with sulfur nucleophiles on electron rich aromatic xanthenes scaffolds in the absence of a metal catalyst. The resulting 3'-thioethers exhibit high photostability and are conveniently converted into r...