Absolute Configuration of Mulinolic Acid

Abstract

The structure of this mulinolic acid consists of a mulinane skeleton and the corresponding isopropyl, methyl, carboxyl and methyl groups at C3, C8, C5, C13, respectively, which are β-oriented, whereas the hydroxyl group at C13 is α-oriented. The cyclopentane (A), ciclohexane (B) and cicloheptene (C) rings are trans (A/B) and (B/C) cis fused, and in an envelope, chair, and twist conformation respectively.In the crystal the molecules are linked by two intermolecular OH⋅⋅⋅O hydrogen bond forming bidimensional supramolecular structures with graph-set notation R4 4 (12), R4 4 (40), R6 6 (46) and C4 4 (46). The absolute configuration of the title compound has been determined from the refinement of the Flack parameter 16 . On this basis the absolute configuration was assigned as C3R, C5S, C8S, C9S, C10S and C13R.

CRYSTAL AND MOLECULAR STRUCTURE OF 14α-ACETOXY-13α-HYDROXYMULIN-11-EN-20-OIC ACID MONOHYDRATE

“…The main differences between the title compound and the similar compounds 17,24 are in the conformation of the C ring, (chair in both compounds). In other closely related compounds, the conformation of the rings A, B and C are retained respect to of the title compound 22,23 .…”

Crystal structure of 5,4′-dihydroxy-7,3′-dimethoxyflavanone, C17H16O6

“…Flora [4][5][6][7][8][9], dried aerial parts of Parastrephia quadrangularis (1030 g) collected in april 2015 in El Tatio, Atacama Desert, Northern Chile. This medicinal plant used by the Aymara Amerindians [10,11], a known producer of several flavonoids and benzoic acid derivatives with antioxidant activity [12][13][14][15].…”