An efficient and greener protocol for the synthesis of 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-one using tetradecyltrimethylammonium bromide (TTAB) at room temperature in water is described.

This minireview describes the syntheses, structure-photophysical properties relationship, and bioimaging applications of fluorescent coumarins, xanthenes, BODIPYs, cyanines. Advantages disadvantages emissive units are also discussed, as general practical issues that need to be considered when using fluorophores in a biological setting.

Several photosensitizing agents, which are activated by illumination with sunlight or artificial light sources, have been shown to be accumulated in significant amounts by a variety of insects when they are administered in association with suitable baits. The subsequent exposure of such insects to UV/visible light leads to a significant drop in survival. Of the photosensitizers tested so far, x...

In the title mol-ecule, C(35)H(22)BrNO(2), the four-membered ring of the β-lactam unit is nearly planar [maximum deviation = 0.003 (3) Å] and makes dihedral angles of 87.07 (15), 59.80 (16) and 20.81 (19)°, respectively, with the xanthene system, the anthracene system and the bromo-substituted benzene ring. The mol-ecular conformation is stabilized by weak intra-molecular C-H⋯O and C-H⋯N hydrog...

An enhanced fluorescent emission of the dye Rhodamine 800 in the Near-IR is observed in the presence of other xanthene dye molecules (RhX) when they are hosted in different matrices due to the formation of a new type of fluorescent J-heteroaggregates. This enhanced emission of the acceptor occurs despite the low spectral overlapping and the low quantum yield of Rh800.

In the title mol-ecule, C(30)H(36)N(4)O(3), the dihedral angle between the planes of the xanthene and spiro-lactam rings systems is 88.69 (4)°. Both C atoms of one of the ethyl groups are disordered over two sites with occupancies 0.72 (2)/0.28 (2). The conformation of the mol-ecule may be influenced by two intra-molecular hydrogen bonds.

Scintillation properties of 14-phenyl-14H-dibenzo[a,j]xanthenes (called material A) is studied. Cyclohexan is used as a solvent, whilst Anthracene and Naphthalene are used as secondary solutes. The response of the scintillator to low energy Gamma-rays is detectable. Our study shows that the addition of material A (0.01 mol L ) to the solution of Anthracene-Naphthalene-Cyclohexan, improves the d...

The title compound, C(35)H(36)N(4)O(4), was prepared as a spiro-lactam ring formation of rhodamine B dye for comparison with a ring-opened form. The xanthene ring system is approximately planar. The r.m.s. deviation from planarity is 0.064 (6) Å for the xanthene ring. The dihedral angles formed by the spiro-lactam and 2,4-dihydroxy-benzene rings with the xanthene ring system are 86.6 (9) and 88...

In the mol-ecule of the title compound, C(24)H(28)O(4), the three six-membered rings of the xanthene system are not planar, having envelope, boat and envelope conformations. In the crystal structure, C-H⋯O hydrogen bonds link the mol-ecules, generating centrosymmetric R(2) (2)(12), R(4) (4)(28) and R(2) (2)(16) ring motifs and forming a three-dimensional network.

In the title compound, C(14)H(10)O(4)·H(2)O, isolated from the roots of Calophyllum membranaceum, the xanthene ring system is almost planar (r.m.s. deviation = 0.008 Å). In the crystal structure, inter-molecular O-H⋯O and O-H⋯(O,O) hydrogen bonds connect the mol-ecules.