The interionic solution structures of trans-[Ru(PMe3)2(CO)(COMe)(pz2-CH2)]BPh4 and trans-[Ru(PMe3)2(CO)(COMe)(η2-pz3-CH)]BPh4 have been “directly” investigated by the detection of interionic contacts in 1H-NOESY NMR spectra between the protons of the organometallic fragments and those of the counterion BPh4 -. A comparison with the solid-state structures obtained by single-crystal X-ray studies has been made.

Highly amphiphilic fragments of hydrolytically stable 3′‐peptidyl transfer RNA analogues are stepwise assembled on solid support. Their secondary structure and thermal denaturation are studied by using CD and UV spectroscopy, their supramolecular assemblage by using AFM and DLS (see picture).

The complexes trans,cis-M(PMe3)2(CO)2(Me)I (M = Fe and Ru, 1a,b) react with bis- and tris(pyrazol-1-yl)methane, in the presence of NaBPh4, affording trans-[M(PMe3)2(CO)(COMe)(pz2-CH2)]BPh4 (2a,b) and trans-[M(PMe3)2(CO)(COMe)(η2-pz3-CH)]BPh4 (3a,b), respectively (pz = pyrazolyl ring). The reactions of 1b with 5,5‘-Me2-pz2-CH2 and 3,5‘-Me2-pz2-CH2 produce trans-[Ru(PMe3)2(CO)(COMe)(5,5‘-Me2-pz2-CH2)]BPh4 (4) and trans-[Ru(PMe3)2(CO)(COMe)(3,5‘-Me2-pz2-CH2)]BPh4 (5), respectively. A mixture of trans,cis-[Ru(PMe3)2(CO)2(η1-3,3‘-Me2-pz2-CH2)(Me)]BPh4 (6) and trans-[Ru(PMe3)2(CO)(COMe)(3,3‘-Me2-pz2-CH2)]BPh4 (7) is obtained from reaction of 1b and 3,3‘-Me2-pz2-CH2. The reactions of 2−7 with nucleophiles either give back the starting complex (Nu = I-) or analogous complexes (Nu = Br- and Cl-) or produce decomposition products of the complexes (Nu = I2, Br2, Cl2, and OMe-). The solid state structures of 2b and 3b were obtained using single-crystal X-ray diffraction. For all complexes, 2−7 as well as complex 8 (analogue to 2a, having a BF4 - counterion instead of BPh4 -), the ion-pair structures and the localization of the counterion in solution with respect to the organometallic moiety were investigated by the detection of interionic contacts in the 1H-NOESY and 19F{1H}-HOESY NMR spectra.

Alginate-based microencapsulation of live cells may offer the opportunity to treat chronic and degenerative disorders. So far, a thorough assessment of physical-chemical behavior of alginate-based microbeads remains cloudy. A disputed issue is which divalent cation to choose for a high performing alginate gelling process. Having selected, in our system, high mannuronic (M) enriched alginates, we studied different gelling cations and their combinations to determine their eventual influence on physical-chemical properties of the final microcapsules preparation, in vitro and in vivo. We have shown that used of ultrapure alginate allows for high biocompatibility of the formed microcapsules, regardless of gelation agents, while use of different gelling cations is associated with corresponding variable effects on the capsules' basic architecture, as originally reported in this work. However, only the final application which the capsules are destined to will ultimately guide the selection of the ideal, specific gelling divalent cations, since in principle there are no capsules that are better than others.

3'-aminoacylamino-3'-deoxyadenosines, analogues of the antibiotic puromycin, have been synthesized from adenosine. They key 3'-azido derivative 10 was obtained through a 3'-oxidation/reduction/substitution procedure. A modified purification protocol on a larger scale was developed for the oxidation step using the Garegg reagent. The coupling reaction between an Fmoc-l-amino acid and the fully protected form of 3'-amino-3'-deoxyadenosine 11 furnished the aminoacylated compounds 12 in high yields. The puromycin analogues were obtained in 10 steps and up to 23% (14c) overall yield.