Resumen de Absolute configuration of 18-acetoxy-cis-cleroda-3,13e-dien-15-oic acid
Iván Brito, Jorge Borquez Ramirez, Diego Robledo, Mario Juan Simirgiotis, Alejandro Cárdenas
In this paper we report the absolute configuration which has been determined from the refinement of the Flack parameter, x = 0.05(5), which indicate that the correct configuration had been assigned against 1353 (99%) CuKα Bijvoet pairs. On this basis the absolute configuration was assigned as C5R, C8S, C9R and C10S. The structure of 18-acetoxy-cis-cleroda-3,13E-dien-15-oic acid consists of a clerodane skeleton and the corresponding methyl groups are α-oriented (C8, C9) while C5 is β-oriented. The acidic lateral chain is β-oriented and the double bond between C13 and C14 has E isomeric. The ciclohexene, cyclohexane rings are cis fused, and in an sofa and chair conformation respectively. In the crystal the molecules are linked by one intermolecular O—H…O hydrogen bond forming 1D-dimensional chain with distance donor-acceptor of 2.060(6)Å with graph-set notation C 1 1(15).
