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.

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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”︁).

Template-directed synthesis has been used to construct a [2]catenane in which the two molecular components, the cyclobis(paraquat-p-phenylene) tetracation and 1,5-dinaphtho-38-crown-10, are found to be ordered non-covalently with respect to each other in both the solid (by X-ray crystallography) and solution (by NMR spectroscopy) states and to influence each other to the extent of establishing electrochemical gradients for the stepwise one electron reductions of the two paraquat units.

Nature has placed an evolutionarily conserved phenylalanine at position 82 of Cc,' and its possible role in electron transfer has long been suspected. We previously reported2 results obtained by using a suite of position 82 mutants of yeast iso-1 Cc that indicated that the rate constant, kb, for the thermal Fe2+P -

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