Prenylated isoflavones from Deguelia costata

Rebeca Lopes Santos 1, Lilian da Silva Migüez 1, Andreza Santos de Jesus 1, Bruno Brito Lemes 1, Lourdes Cardoso de Souza Neta 1
1. Universidade do Estado da Bahia (UNEB) Campus I
R. Silveira Martins, 2555 - Cabula, Salvador - BA, 41150-000
[email protected]

Isoflavonoids are secondary metabolites that belong almost exclusively to the Papilionoideae subfamily of Fabaceae1. Phytochemical studies of the species from the Deguelia genus (Fabaceae) highlighted that the following classes of compounds were mainly produced by this genus isoflavones, 4-hydroxy-3-phenylcoumarins, rotenones, and stilbenes2,3. In this context, two new prenylated isoflavones (1-2 – Figure 1) were isolated from the dichloromethane extract from the heartwood and leaves, respectively, of the Deguelia costata (Benth.) A. M. G. Azevedo. The compounds were purified by successive fractionations of the extracts by chromatographic methods (silica gel column and preparative thin layer chromatography). Their structural formulas were elucidated by analysis of the data of IR, UV, HRESIMS,1D and 2D NMR spectra3. The isolation and characterization of these compounds contributed to the chemotaxonomy of the genus Deguelia. It is intended to continue the phytochemical study and evaluate the antimicrobial activity of the compounds and fractions obtained.

Figure 1. Chemical structure of new isoflavones (1-2) isolated from D. costata.

Acknowledgements:
The authors thank CAPES, FAPESB, CNPq, LABAREMN, UNEB and PGQA.

References:
1- MACHADO, L. M. V. Estudo fitoquímico das raízes de Platycyamus regnellii. 2000. 92 p. Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química, Campinas, SP.
2- MARQUES, E. J; SERAFIM, J. C. R. B.; LEMES, B. B. Occurrence and Distribution of Polyphenolics in Species of Deguelia (Leguminosae). Journal of Microbial & Biochemical Technology, v. 7, n. 6, p. 327–333, 2015.
3- LEMES, B. B. et al. Two new prenylated isoflavones from Deguelia costata. Phytochemistry letters, v. 30, p. 181-185, 2019.