ABSTRACT
Evolution of the theoretical spectrum during the course of spectrum analysis and comparison of the result with the experimental spectrum.
ABSTRACT
The novel algorithm for a total lineshape analysis of high-resolution NMR spectra has been developed. A global optimization by simulated annealing has been applied that has allowed to overcome the main trouble of common approaches which had frequently returned solutions for local minima rather than for global ones. The algorithm has been verified for the four-spin test systems ABCD, and has been successfully used for analysis of experimental NMR spectra of proline. The approach has allowed to avoid a sophisticated manual setup of initial parameters and to conduct the analysis of complicated high-resolution NMR spectra nearly automatically.
ABSTRACT
Synthesis of tetraphenyl-substituted porphyrins with tret-butyl and methoxycarbonyl groups in meso-aryl radicals is described. It is shown that, during the condensation of dipyrromethanes with substituted benzaldehydes, a rearrangement occurs with the formation of a mixture of isomeric porphyrins. The character of these rearrangements depends on the position of substituents in the starting compounds.
