Martínez-Cifuentes, M.Cardona, W.Saitz, C.Weiss-López, B.Araya-Maturana, R.2017-11-242017-11-242017-04Molecules. Volume 22, Issue 4, April 2017, Article number 5931420-3049DOI: 10.3390/molecules22040593http://repositorio.unab.cl/xmlui/handle/ria/4723Indexación: Web of Science; Scopus.A theoretical exploration about hydrogen bonding in a series of synthetic regioisomeric antitumor tricyclic hydroquinones is presented. The stabilization energy for the intramolecular hydrogen bond (IHB) formation in four structurally different situations were evaluated: (a) IHB between the proton of a phenolic hydroxyl group and an ortho-carbonyl group (forming a six-membered ring); (b) between the oxygen atom of a phenolic hydroxyl group and the proton of an hydroxyalkyl group (seven membered ring); (c) between the proton of a phenolic hydroxyl group with the oxygen atom of the hydroxyl group of a hydroxyalkyl moiety (seven-membered ring); and (d) between the proton of a phenolic hydroxyl group and an oxygen atom directly bonded to the aromatic ring in ortho position (five-membered ring). A conformational analysis for the rotation around the hydroxyalkyl substituent is also performed. It is observed that there is a correspondence between the conformational energies and the IHB. The strongest intramolecular hydrogen bonds are those involving a phenolic proton and a carbonyl oxygen atom, forming a six-membered ring, and the weakest are those involving a phenolic proton with the oxygen atom of the chromenone, forming five-membered rings. Additionally, the synthesis and structural assignment of two pairs of regioisomeric hydroquinones, by 2D-NMR experiments, are reported. These results can be useful in the design of biologically-active molecules.enAIMDFTHydrogen bondHydroquinoneNBOArtículo