CRYSTALLINE STRUCTURE AND HIRSHFELD SURFACE ANALYSIS OF 7-((6-HYDROXY-2,5,5,8A-TETRAMETHYL-1,4,4A,5,6,7,8,8A OCTAHYDRONAPHTHALEN-1-YL)METHOXY)-2H-CHROMEN-2-ONE ISOLATED FROM FERULA PERSICA ROOTS: A NEW ENANTIOMORPH AT 100K

An ethanol extract was obtained from the underground part of Ferula persica Wild., collected during the fruiting phase, which, after the solvent removal, was chromatographed on a column with neutral “Alumina” (II degree of activity) and eluted with hexane, benzene, and their mixtures in a gradient of increasing polarity. As a result, 7-((6-Hydroxy-2,5,5,8a-tetramethyl-1,4,4a,5,6,7,8,8a-octahydronaphthalen-1-yl)methoxy)-2H-chromen-2-one (conferol - m.p. 137–138 ºC), was isolated. To confirm the structure, we used X-Ray, NMR 1H, 13C NMR, DEPT, COSY, HSQC, and HMBC methods. It has been previously mentioned about crystalline structure of the given compound C24H30O4, isolated from F. persica roots at room temperature. Unlike literature data in this study crystalline structure was determined with higher precision at 100 K (-173 ºC). The compound being investigated consists of octahydronaphthalene fragment, attached to the chromen-2-one fragment through an oxymethylene bridge. The title compound is a new enantiomorph of the one reported previously. In the crystal the molecules are connected by C—H···O hydrogen bonds along the c-axis forming the layers parallel to the (010) plane, while molecules are linked by O—H···O hydrogen bonds, which generate R22(6) motifs along the a-axis. The C—H···π and van der Waals interactions between these layers stabilize and maintain the structure. The Hirshfeld surface analysis indicates that the most important contribution to the crystal packing are from H···H (58,3%), O···H/H···O (21,8%) and C···H/H···C (19,7%) contacts.