tided as ca. 99% unreacted 'H NMR (vide supra). The components of the aqueous phase were identified by 'H NMR as paraquat (S 4.35 (s, 3 H), 8.37 (d, J = 1,2 H), 8.90 (d, J = 1,2 H)) and 2-(ethylamino)-2-methylpropanol hydrochloride (spectrum identical to that described above). Integrals of the NMR signals for paraquat and the amino alcohol indicated a 2.5% conversion of DEM-3 dimer to the amino alcohol.B. Buffered Methanol Medium. The reaction was performed in pH 7, Tris-buffered methanol. This time the reaction mixture turned dark blue. Again, the residue from solvent evaporation was extracted into 1 mL of D20 and 1 mL of CDC13. The components of the organic phase were identified by 'H NMR as DEM-3 dimer and 2-(ethylamino)-2methylpropanol (6 1.06 (s, 6 H), 1.07 (t, J = 7.2, 3 H), 2.44 (q, J = 1.2, 2 H), 3.33 (s, 2 H)). The components of the aqueous phase were identified as paraquat and a small amount of 2-(ethylamino)-2-methylpropanol hydrochloride, also from the 'H NMR spectrum. Integrals of the NMR signals indicated a 41% conversion of DEM-3 dimer to amino alcohol.Attempted Reduction of Daunomycin with DEM-3 Dimer. The reaction vessel was a 9 mm X 20 cm Pyrex tube equipped with a 2.5-cm side arm. The side arm was charged with 2.65 X 10"* mol of DEM-3 dimer dissolved in methylene chloride, and the methylene chloride was evaporated with a stream of nitrogen. The main tube was charged with 2 mL of 2 X 10~3 M 1:1 Tris/Tris-HCl buffered methanol containing 2.66 X 10"6 mol of daunomycin. The methanol solution was freeze-thaw-degassed, and the tube was sealed with a torch. After mixing the reagents, the solution was heated at 36 °C for 18 h. C-18 reverse-phase HPLC analysis as described earlier35 showed no formation of 7-deoxydaunomycinone.

A template‐controlled, one‐pot reaction afforded the [2]catenane 1 in 70% yield. Compound 1 consists of π‐electron‐rich decaoxa[13.13]paracyclophane (empty circles) and an electron‐deficient macrocycle made up of two paraquat p‐phenylene units (filled circles). Dynamic 1 H NMR spectroscopy and cyclovoltammetry showed that 1 is highly ordered not only in the solid state but also in solution.

The high hydroxy (OH) group content in carbohydrates makes the study of carbohydrate OH···XH and OH···X Hbond energetics fundamental to understanding of carbohydrate recognition. There is, however, a relative lack of knowledge concerning the factors that allow a carbohydrate to participate in recognition events stabilised by intermolecular H bonds. We therefore present here a systematic study on the factors that determine the formation of a well-defined intramolecular H-bonding network between carbohydrate hydroxy groups, and its cooperative or anti-cooperative influence on selected intermolecular processes mediated by H bonds. With this in mind, we first determined the H-bonding networks of a series of carbohydrate derivatives − monoalcohols, 1,2-and 1,3-diols and amidoalcohols − by 1 H NMR and FT-IR spectroscopy. The hydroxy groups of these compounds showed different abilities to form intramolecular H bonds, depending on their relative positions and configurations on

Changing employment: Receptor 1 binds β‐N‐acetylglucosaminyl (β‐GlcNAc) up to 100 times more strongly than it does glucose. This synthetic lectin shows affinities similar to wheat germ agglutinin (WGA), a natural lectin used to bind GlcNAc. Remarkably, 1 is more selective than WGA. It favors especially the glycoside unit in glycopeptide 2, a model of the serine‐O‐GlcNAc posttranslational protein modification.

Eine templatgesteuerte Eintopfreaktion liefert in 70% Ausbeute das [2]‐Catenan 1, das aus π‐elektronenreichem Decaoxa[13.13]paracyclophan (offene Kreise) und einem elektronenarmen Makrocyclus mit zwei Paraquat‐p‐phenylen‐Einheiten (schwarze Kreise) besteht. Wie durch dynamische 1H‐NMR‐Spektroskopie und durch Cyclovoltammetrie gezeigt wurde, ist 1 nicht nur im Festkörper, sondern auch in Lösung hoch geordnet. („a catenane made to order”︁).