A fully conjugated system 4 consisting of two 2-aza-21-carbaporphyrin (NCP) subunits bridged by dipyrrin was synthesized by a highly selective condensation of 3-pyrrole-NCP 2 with aryl aldehydes. The free base 4 as well as its silver(III) complex 5 exhibited flexibility of the bridge allowing synergetic binding of Ag , thus leading to a mixed-valence tetraporphyrinic assembly consisting of eight silver atoms which was characterized both in the solid state and in solution. Binding of chiral acid by 4 and 5 was shown by observation of an induced optical activity of the adducts.
View Article and Find Full Text PDFReaction of paraformaldehyde with meso-tetraaryl-2-aza-21-carbaporphyrins (NCP) in the presence of a basic catalyst afforded fused lactam derivatives comprising a >C═O bridge linking the internal carbon C21 with one of the internal nitrogens. The isomer 2 with C21-C(O)-N24 bridge is formed with about 9-fold molar excess over that with C21-C(O)-N22 bridge (3). The (1)H NMR and UV-vis spectral characteristics indicate aromatic character of the derivatives.
View Article and Find Full Text PDFThe goal of this study was to assess effectiveness of a short collective stress inoculation training (SIT) conducted according to the methodology of the Virtual Reality Medical Center of San Diego (Training of Physiological Control Exposure to Virtual Stressor while Maintaining Physiological Control). The results obtained indicate a short-term effectiveness of the training as a method of tension reduction. However, in the long-term perspective these results are ambiguous and they suggest a need of further research.
View Article and Find Full Text PDFBis- and tris(methylated) derivatives of 3,3'-bis(N-confused porphyrin) were obtained. Methylation of C21 stabilizes the geometry of the axially chiral system allowing separation of enantiomers and assignment of an absolute configuration by X-ray methods.
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