The Two Pathways for Effective Orthogonal Protection of L-Ornithine, for Amino Acylation of 5-O-Pivaloyl Nucleosides, Describe the General and Important Role for the Successful Imitation, During the Synthesis of the Model Substrates for the Ribosomal Mimic Reaction

Abstract

Bz(NO(2))-Orn(Boc)-OCH(2)CN was synthesized as an amino acid component with effective and successful orthogonal protection for amino acylation of 5'-O-Pivaloyl nucleosides and preparation of substrates for model ribosome reactions. The synthesis was carried out using suitable combinations of the methods of peptide synthesis and modification of amino acids.

A Novel General Methodology for Ribozyme-Mimetic Synthesis of Methyl Esters of Various Natural Amino Acids, Simulating the Prebiotic Biomolecule Creation

“…But this small percent decreases, when the solution (reaction mixture) is diluted. Paecht et al [38] also described the formation of amino acid dimmers and oligomers: trimers, tetramers, pentamers, hexamers etc. as a side reaction during their procedure of phosphorylation of AMP with aminoacyl phosphate at hydrous conditions [38].…”

Optimized syntheses of Fmoc azido amino acids for the preparation of azidopeptides

“…Protected acid 37 was prepared by the reaction of 35 (10.2 g; 19.4 mmol) and 8-quinolinol (7.3 g; 50.4 mmol), using the method described previously [56][57][58][59]…”

“…The strategy of orthogonal functional group protection [56][57][58][59] of L-ornithine and L-lysine is usually used for the synthesis of their azido derivatives.…”

Successful Application of the Lipase as a Catalyst in the Combinative Approach, Using an Efficient and Selective Iterative Procedure for the Chemo-Enzymatic Alpha-Amino Group Protection in the Natural Amino Acids, Representing the Ornithyl Model System as a Starting Research Pattern: Homogeneous and Heterogeneous Synthesis

“…Also it is forwarded, that the synthesis of cyclic aliphatic, aromatic as well as aliphatic-aromatic esters (alcohol synthons) of the above noted protective groups (acyl synthons) as synthetic equivalents and the study of their reactive ability will be realized. [6,7,32], and the general and important role of A76 2'-OH in the ribose ring of peptidyl-tRNA for acceleration of peptidyl transferase reaction, during the protein biosynthesis on ribosome [33,34]. On the other hand the amino acid was used as its methyl ester, as well as it was used with its carboxyl free functional group, which determines the combinative approach, related to the selection of solvents media and lipase determination (free or immobilized).…”

“…The hydrolysis of the amino acid methyl ester is much more embarrassed, than the aminolysis reaction of activated esters of a variety of protective groups, probably due to the higher enzyme selectivity towards the bulky acyl synthon, and towards the hydrophobic alcohol synthon, playing the role as a good nucleophuge (leaving group) in the acyl ester synthetic equivalent of the acyl components ϯ . Thus, the significant percent of hydrolytic product, due to the hydrolysis reaction is possible only in the cases, when the methyl esters of substrates are incubated in the reaction mixture with lipase for a time, more than 48 hours and under different conditions [32]. In the case, when a negligible amount of the hydrolytic product exists, two ways for the solving of the problem are possible, by the product purification (additionally working up of the reaction mixture).…”