Compounds I, II and III, were used as models resembling gear systems (bods connecting CR3 groups to the skeletal molecule are parallel) in surveying the potential energy surface for their internal rotation. The magnitude of the barriers calculated for averaging the NMR signals, placed these compounds in the range of measurement accessible by dynamic NMR spectroscopy (which is cur...

The cage of 2,5-di-aza-bicyclo-[2.2.1]heptane is frequently employed in synthetic chemistry as a rigid bicyclic counterpart of the piperazine ring. The 2,5-di-azabicyclo-[2.2.1]heptane scaffold is incorporated into a variety of compounds having pharmacological and catalytic applications. The unsubstituted parent ring of the system, 2,5-di-aza-bicyclo-[2.2.1]heptane itself, has not been structur...

The crystal structures of the new compounds spiro[cyclohexane-1,3’-indol]-2’(1’H)-one (1), (rel-1R,2S)-spiro[bicyclo[2.2.1] heptane-2,3’-indol]-2’(1’H)-one (2) and spiro[indole-3,2’-tricyclo[3.3.1.1]decan]-2(1H)-one (3) have been determined by low temperature single crystal X-ray diffraction. The effects of substitution on the hydrogen bonding pattern is compared between all three compounds.

The title compound, C(16)H(19)NO, was synthesized under solvent-free conditions by reaction of 7-oxa-bicyclo-[4.1.0]heptane and naphthalen-1-amine in the presence of Ca(CF(3)COO)(2) as catalyst. The cyclo-hexane ring adopts a chair conformation. In the crystal, mol-ecules are linked by inter-molecular N-H⋯O hydrogen bonds and C-H⋯π inter-actions into chains parallel to the c axis.

In the title mol-ecule, C(18)H(18)F(2)N(2)O(2)S, the two benzene rings, which are oriented in opposite directions with respect to the rigid 2,5-diaza-bicyclo-[2.2.1]heptane core, form a dihedral angle of 17.2 (1)°. Weak inter-molecular C-H⋯O, C-H⋯F and C-H⋯N contacts consolidate the crystal packing.

The relationship between the binding of sodium n-dodecyl sulphate and protons to histone H1 has been investigated by equilibrium dialysis and titrimetry. The data cover the pH range 3.2-10 and surfactant concentrations up to 3.0×10-3 mol dm-3. A theoretical approach based on the binding potential concept of Wyman is presented and has been used to make estima...

In the crystal structure of the title complex, [Cd(C(8)H(8)O(5))(C(3)H(4)N(2)S)(3)]·2H(2)O, the Cd(II) atom exhibits a slightly distorted octa-hedral CdO(3)N(3) coordination, defined by the bridging O atom of the bicyclo-heptane unit, two O atoms from the carboxyl-ate groups and by three N atoms from three 2-amino-thia-zole ligands. Uncoordinated lattice water mol-ecules are also present in the...

7-Aza-bicyclo-[2.2.1]heptane (7-aza-norbornane) is a bridged heterocyclic nucleus found in epibatidine, the alkaloid isolated from the skin of the tropical poison frog Epipedobates tricolor. Since epibatidine is known as one of the most potent acetyl-choline nicotinic receptor agonists, a plethora of literature has been devoted to this alkaloid. However, there are no structural data on the unsu...