Anthraquinone derivatives form an important class of dyes and are also known for their medicinal properties. Recently, 2,3-disubstituted anthraquinones have been shown unexpectedly to jellify various organic solvents. No information on the packing mode of these derivatives was known.
View Article and Find Full Text PDFNew coordination polymers of the formula [M(btre)(2)(NCS)(2)] (btre = 1,2-bis(1,2,4-triazol-4-yl)ethane; M(II) = Fe, Co) have been synthesized, and their crystal structures have been determined at 293 K by X-ray analysis. The Fe(II) compound (C(7)H(8)FeN(7)S(2)) crystallizes in the monoclinic space group P2(1)/n, a = 12.439(5) A, b = 8.
View Article and Find Full Text PDFThe utilization of tetrahedral pre-formed coordination compounds {M(C2O4)4}4- (M = Zr(IV), U(IV); C2O4(2-) = oxalate) permitted the efficient construction of rare examples of heteronuclear supramolecular nano-porous architectures. A series of metal-organic coordination frameworks prepared by association of these building units with either Mn2+, Cd2+, or Mg2+ have been structurally characterized and are described. Their 3-D chemical scaffold is based on the primary tetrahedral building unit but their pore sizes and topologies could be varied through the M2+ metal ion involved in the assembling process, and the anionic tetrahedral moiety.
View Article and Find Full Text PDFThe utilization of the tetrahedral pre-formed coordination compound {U(C(2)O(4))(4)}(4-) permitted the efficient synthesis of a 3D heteronuclear supramolecular nano-porous architecture undergoing a reversible sorption process without collapsing.
View Article and Find Full Text PDFThe comparative photostability of curcumin 1, and two non-phenolic curcuminoids: 1,7-diphenyl-1,6-heptadiene-3,5-dione 2 (unsubstituted curcumin) and dimethylcurcumin 3 in non-degassed dilute solutions (approximately 3-5 x 10(-5) mol l(-1)) has been established by UV-visible absorption spectroscopy; disappearance quantum yields were measured. The similar behavior of the three studied curcuminoids is indicative of only a moderate role of phenol groups in the photodegradation process. Structural analysis of the photodegradation products of compound 2 in more concentrated solution (approximately 3.
View Article and Find Full Text PDF[Fe(hyptrz)3](4-chloro-3-nitrophenylsulfonate)22 H2O (1; hyptrz=4-(3-hydroxypropyl)-1,2,4-triazole) has been synthesized and its physical properties have been investigated by several physical techniques including magnetic susceptibility measurements, calorimetry, and Mössbauer, optical, and EXAFS spectroscopy. Compound 1 exhibits a spin transition below room temperature, together with a very wide thermal hysteresis of about 50 K. This represents the widest hysteresis loop ever observed for an FeII-1,2,4-triazole spin transition material.
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