Promiscuous Zinc‐Dependent Acylase‐Mediated One‐Pot Synthesis of Monosaccharide‐Containing Pyrimidine Derivatives in Organic Medium

Abstract

A facile one-pot synthesis route to monosaccharide-containing pyrimidine derivatives was developed by combining the two types of catalytic activities of one enzyme in an organic medium, i.e., the Michael addition/acylation activities of zinc-dependent d-aminoacylase (DA) from Escherichia coli. First, the stepwise approach was investigated. DA showed higher activity towards the Michael addition than acylation in this reaction system. The enzymatic Michael additions of pyrimidines to vinyl acrylate proceeded very rapidly and the initial reaction rates for the Michael addition of pyrimidines to vinyl acrylate were 7.2-16.5 mM min À1. The catalytic specificity of aminoacylases toward Michael addition was demonstrated by the combination of different control experiments. Then, the two steps could be performed in one pot and a single aminoacylase catalyzed onepot biotransformation was constructed. Using this strategy, a series of saccharide-pyrimidine complexes with potentially biological and pharmacological applications was prepared efficiently. This high Michael addition activity of zinc-dependent aminoacylases and the novel single aminoacylase-catalyzed one-pot synthesis combining two catalytic activities in vitro is of practical significance in expanding the application of enzymes and in the evolution of new biocatalysts.

Hydrolases: catalytically promiscuous enzymes for non-conventional reactions in organic synthesis

“…Thus, already mentioned D-aminoacylases have catalyzed the Michael addition of pyrimidines to vinyl acrylates in combination with their natural ability to catalyze the regioselective acylation of carbohydrates in organic media (DMF or DMSO) leading in an one-pot biotransformation to monosaccharide-containing pyrimidine derivatives, compounds with potential biological and pharmacological applications (Scheme 25). 42 Similarly the combination of a regioselective acylation of glucose followed by a Michael addition with N-substituted imidazole derivatives led to imidazole-sugar conjugates in an one-pot procedure using a single enzyme (alkaline protease from Bacillus subtilis) for a two-step synthesis without intermediate recovery steps. 43 A similar example was reported by the same authors related to the synthesis of pyrimidine derivatives containing a sugar branch by combining two enzymatic processes: A lipasecatalyzed Michael addition and a protease-catalyzed acylation reaction, where the first step was mediated by Amano lipase M and the succeeding acylation by alkaline protease from Bacillus subtilis.…”

Lipase-catalyzed domino Michael–aldol reaction of 2-methyl-1,3-cycloalkanedione and methyl vinyl ketone for the synthesis of bicyclic compounds

“…In contrast, only a few reports on promiscuous, single enzyme-catalysed, multi-step or domino reactions have been described. [20][21][22] While a lipase-catalysed domino reaction of Wieland-Miescher ketone was recently reported, no stereoselectivity was observed. [23] (Scheme1)…”