Absorption spectra of dysprosium compounds in nonaqueous solutions. Spectral intensity analysis

Absorption spectra of dysprosium compounds were measured in amides and D₂O within the 5500–35000 cm^?1 region and in alcohols within the 7000–34300 cm^?1 region. The oscillator strengths of f-f absorptions bands below 35000 cm^?1 were determined. The intensities of the Dy³⁺ ground state absorption were analyzed according to the Judd-Ofelt theory of forced electric dipole transitions.A good fit to the measurements was obtained with the intensity parameter given in Tables 4–6. The polarizability effect on the intensity of the f-f transition with high value matrix elements U⁽⁴⁾ and U⁽⁶⁾ were considered.     

BIODISTRIBUTION AND PDT EFFICACY OF A KETOCHLORIN PHOTOSENSITIZER AS A FUNCTION OF THE DELIVERY VEHICLE

Abstract C8KC is a new ketochlorin photosensitizer that must be formulated with an emulsifier because of its poor water solubility. In this report, we compare properties of Cremophor EL (CRM) and Tween 80 as delivery vehicles for C8KC. Unlike Tween 80, CRM altered the physical properties of both human and mouse plasma lipoproteins, resulting in decreased electrophoretic mobility of the individual lipoproteins along with the formation of a l ipoprotein degradation product: a phospholipid fraction of low buoyant density. In human plasma, where there was sufficient low-density lipoprotein (LDL) for a distinction to be made, CRM caused a shift in binding of a ketochlorin from albumin to LDL and the degraded lipoprotein fraction. In mice bearing the RIF tumor, the use of CRM for drug formulation was associated with longer plasma and tissue persistence of C8KC, and enhanced photodynamic therapy (PDT) efficacy. These results indicate the importance of both sensitizer and vehicle as determinants of PDT efficacy.     

On the tri-n-octylammonium chlorocomplexes of Sn(IV) in benzene solution

Extracts with tri-n-octylammonium chlorocomplexes of Sn(IV) of various compositions, included the N-deuterated compounds, were prepared and investigated by IR spectroscopy and conductivity measurements. Three Sn(IV) complexes were found: (TOAH⁺)₂SnCl₆^2? (2:1-complex), TOAH⁺SnCl₅^? (1:1-complex) and a complex with the stoichiometric ratio TOA:Sn(IV) > 2. The cation of the latter contains the groups (TOAH…Cl…HTOA)⁺ and TOAH⁺ and that species is supposed to be a 3:1-complex (TOAH…Cl…HTOA)⁺TOAH⁺SnCl₆^2?.     

Synthesis of a versatile functionalized tetraquinane. Convenient access to 1,3-bishomopentaprismanedione

The tetracyclic diene dione 1 has been synthesized by a short oxidative decarboxylation route starting with the domino Diels-Alder adduct 2. Photocyclization of the bisketal of 1 was used to arrive expediently at 1,3-bishomopentaprismanedione (7).