-Molecule-2-is-the-corresponding-open-porphyrinoid-nanotube-g

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Molecule 3 is a clam-like porphyrinoid cage, whose shells consist of fused Zn-porphyrins, and the two halves are connected via butadiyne bridges. Molecule 4 is a cross-belt of fused Zn-porphyrins, and molecule 5 is a cross-belt of Zn-porphyrins connected with butadiyne bridges. The magnetically induced current density of the optimized porphyrinoid cages was calculated for determining the aromatic character, the degree of aromaticity and the current-density pathways. The current-density calculations were performed at the DFT level with the gauge─including magnetically induced currents (GIMIC) method using the B3LYP hybrid functional and def2-SVP basis sets. Calculations of the current densities show that molecule 2 sustains a paratropic ring current around the nanotube, whereas sealing the ends as in molecule 1 leads to an almost nonaromatic nanotube. Fusing porphyrinoids as in molecules 3 and 4 results in complicated current-density pathways that differ from the ones usually appearing in porphyrinoids.

The aromatic character of molecules 4 and 5 changes upon oxidation. The neutral molecule 4 is antiaromatic, whereas the dication is nonaromatic. Molecule 5 is nonaromatic, and its dication is aromatic.Experimental (FT-IR, FT-Raman, 1H NMR) and theoretical study of magnesium, calcium, strontium, and barium picolinates.The experimental IR, Raman, and 1H NMR spectra of picolinic acid, as well as magnesium, calcium, strontium, and barium picolinates were registered, assigned and studied. Characteristic changes in the spectra of metal picolinates in comparison with the spectrum of ligand were observed, which lead to the conclusion that perturbation of the aromatic system of picolinates increases along with the series Mg-->Ca-->Sr-->Ba. Theoretical structures of beryllium and magnesium picolinates, as well as theoretical IR spectrum of magnesium picolinate were calculated in B3PW91/6-311++G(d, p) level.

On the basis of calculated bond lengths in pyridine ring geometric, aromaticity indexes HOMA were calculated. The idea of these indexes is based on the fact that the essential factor in aromatic stabilization is the pi delocalization manifested in: planar geometry, equalization of the bond lengths and angles, and symmetry. The decidedly lower value of HOMA for magnesium picolinate (i.e. 045; 039) than that for beryllium picolinate (i.e. 098; 098) indicate higher aromatic properties of Be picolinate than of Mg picolinate.

salcaprozate sodium of theoretical and literature experimental structures of magnesium picolinate was done. The experimental structure contains two water molecules, so the calculations for hydrated magnesium picolinate were carried on, and the influence of coordinated water molecule on the structure of picolinates was discussed. The HOMAs for hydrated experimental and calculated Mg picolinate amount to 070; 043, and 000; 090, respectively, whereas for anhydrous structure, it is as described above, i.e. 045; 039. Thus, the calculations clearly showed that water molecules coordinated to the central atom weakens the effect of metal on the Solubility enhancement of some water-insoluble drugs in the presence of The solubilities of five poorly water-soluble drugs, diazepam, griseofulvin, progesterone, 17 beta-estradiol, and testosterone, were studied in the presence of nicotinamide. All solubilities were found to increase in a nonlinear fashion as a function of nicotinamide concentration.

The K1:1 and K1:2 stability constants were as follows: for diazepam, K1:1 = 53 M-1 and K1:2 = 8 M-2; for griseofulvin, K1:1 = 54 M-1 and K1:2 = 82 M-2; for progesterone, K1:1 = 58 M-1 and K1:2 = 427 M-2; for 17 beta-estradiol, K1:1 = 58 M-1 and K1:2 = 36 M-2; and for testosterone, K1:1 = 57 M-1 and K1:2 = 277 M-2. Two aliphatic analogues of nicotinamide (nipecotamide and N,N-dimethylacetamide) were studied as ligands with diazepam and griseofulvin and were found to increase the solubilities of both drugs in a linear fashion. The aromatic analogue, N,N-diethylnicotinamide, showed a nonlinear solubilization relationship similar to that seen with nicotinamide. In addition, three other aromatic analogues (isonicotinamide, 1-methylnicotinamide iodide, and N-methylnicotinamide) were studied. These ligands were not soluble enough in water to be studied over the wide range of concentrations used for nicotinamide and N,N-diethylnicotinamide; however, in the concentration range studied, these ligands solubilized diazepam and griseofulvin to a degree similar to that observed with comparable concentrations of nicotinamide. These results suggest that the aromaticity (Pi-system) of the pyridine ring is an important factor in complexation because the aromatic amide ligands were found to enhance the aqueous solubilities of the test drugs to a greater extent than the aliphatic amide ligands.( cyanocobalamin salcaprozate from an endophytic fungus, Colletotrichum sp.

The new (22E,24R)-3-acetoxy-19(10-->6)-abeo-ergosta-5,7,9,22-tetraen-3beta-ol isolated from Colletotrichum sp., an endophytic fungus isolated from Ilex canariensis from Gomera. The structures of these compounds were elucidated by detailed spectroscopic analysis, comparison with reported data, and chemical interconversion.