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The total synthesis of decarboxyaltenusin (5’-methoxy-6-methyl-[1,1’-biphenyl]-3,3’,4-triol), a toxin produced by various mold fungi, has been achieved in seven steps in a yield of 31% starting from 4-methylcatechol and 1-bromo-3,5-dimethoxybenzene, where the longest linear sequence consists of five steps. The key reaction was a palladium-catalyzed Suzuki coupling of an aromatic boronate with a brominated resorcin derivative.

Sulfonate-based inorganic-organic hybrid nanoparticles (IOH-NPs) with the general saline composition [Gd(OH)]2+n/2[ Rdye(SO3) n] n- showing optical absorption and emission in the blue to red spectral regime are presented for the first time. All IOH-NPs are prepared via straightforward aqueous synthesis and instantaneously result in colloidally highly stable suspensions with mean particle diameters of 40-50 nm and high zeta potentials (-20 to -40 mV at pH 7.0). Specifically, the IOH-NPs comprise [Gd(OH)]2+2[CSB]4-, [Gd(OH)]2+2[DB71]4-, [Gd(OH)]2+[NFR]2-, [Gd(OH)]2+[AR97]2-, and [Gd(OH)]2+2[EB]4- showing blue, orange, red, and infrared absorption and emission ([CSB]: Chicago Sky Blue; [DB71]: Direct Blue 71; [NFR]: Nuclear Fast Red; [AR97]: Acid Red 97; [EB]: Evans Blue). The novel IOH-NPs are characterized by electron microscopy, dynamic light scattering, infrared spectroscopy, energy-dispersive X-ray analysis, thermogravimetry, elemental analysis, and fluorescence spectroscopy. In vitro studies based on HeLa and HUVEC cells were exemplarily performed with [Gd(OH)]2+2[EB]4- IOH-NPs and show intense fluorescence and only moderate toxicity at concentrations of 1 to 10 μg/mL. Based on aqueous synthesis, good colloidal stability, absence of severely toxic metals (e.g., Cd2+, Pb2+), use of molecular dyes that are already known for staining in cell biology and histology, extremely high dye load per nanoparticle (70-80 wt %), and blue to red absorption and fluorescence, the sulfonate-based IOH-NPs can be highly interesting for staining, fluorescence microscopy, and optical imaging.

A range of novel cyclometalated ruthenium(II) and iridium(III) complexes with a steroidal backbone based on androsterone were synthesized and characterized by NMR spectroscopy and X-ray crystallography. Their cytotoxic properties in RT112 and RT112 cP (cisplatin-resistant) cell lines as well as in MCF7 and somatic fibroblasts were compared with those of the corresponding nonsteroidal complexes and the noncyclometalated pyridyl complexes as well as with cisplatin as reference. All steroidal complexes were more active in RT112 cP cells than cisplatin, whereby the cyclometalated pyridinylphenyl complexes based on