Publications
2015
Facile rearrangements of a vinylogous α-hydroxy-β-dicarbonyl substrate involving an apparent oxirane C–C bond scission. Kučera, R.; Hylse, O.; Babiak, M. and Švenda, J.*
Tetrahedron Lett. 2015, 56, 6171−6173.
α-Hydroxy-β-dicarbonyls are known to undergo base-induced rearrangement to α-acyloxy carbonyls by a mechanism believed to involve an oxirane C-C bond scission step. Herein, we report the first example of this process in a vinylogous system. An attempt to access the protected form of the putative oxirane intermediate revealed an additional rearrangement pathway that was available to the substrate. Oxirane C-C bond cleavage mechanisms were invoked to explain both isomerizations.
Site-specific Analysis of Protein Hydration Based on Unnatural Amino Acid Fluorescence. Amaro, M.; Brezovský, J.; Kováčová, S.; Sýkora, J.; Bednář, D.; Němec, V.; Lišková, V.; Kurumbang, N.; Beerens, K.; Chaloupková, R.; Paruch, K.*; Hof, M.*; Damborský, J.*
J. Am. Chem. Soc. 2015, 137, 4988.
Hydration of proteins profoundly affects their functions. We describe a simple and general method for site-specific analysis of protein hydration based on the in vivo incorporation of fluorescent unnatural amino acids and their analysis by steady-state fluorescence spectroscopy. Using this method, we investigate the hydration of functionally important regions of dehalogenases. The experimental results are compared to findings from molecular dynamics simulations.
Synthesis of carbocyclic analogs of dehydroaltenusin: Identification of a stable inhibitor of calf DNA polymerase a. Kováčová, S.; Adla, S. K.; Maier, L.; Babiak, M.; Mizushina, Y.; Paruch, K.*
Tetrahedron 2015, 71, 7575.
Syntheses of carbocyclic analogs of dehydroaltenusin tautomers are reported. Both target compounds, cDHA (2,8-dihydroxy-6-methoxy-10a-methyl-10,10a-dihydrophenanthrene-3,9-dione) and cDHAs (4′,5-dihydroxy-6′-methoxy-2-methylspiro[cyclohexa[2,5]diene-1,1′-indene]-3′,4(2′H)-dione), were prepared from 3,5-dimethoxybenzaldehyde in 11 and 13 steps, respectively. Unlike dehydroaltenusin, both cDHA and cDHAs are stable and their structures were confirmed by X-ray crystallography. Compound cDHA was found to be active against calf DNA polymerase α but not related isozymes, while the spirocyclic analog cDHAs was inactive.