A Phytochemical Investigation of Homalium ceylanicum

Abstract

Vacciniin [4] (6-O-benzoyl-D-glucopyranoside) and two new benzenoid glucosides, homaloside A [1] (1''-O-benzyl-3''-O-benzoyl-alpha-L-arabinopyranosyl(1'''-->4'')- beta-D-glucopyranoside) and homaloside D [2] [1-(1'-hydroxy-6'-oxocyclohex-2'-ene-carboxymethyl)- 5-hydroxyphenyl-6''-O-benzoyl-beta-D-glucopyranoside], were isolated from the n-BuOH fraction of Homalium ceylanicum (Flacourtiaceae). A novel cyclohexenone carboxylic acid ester, 1-hydroxy-6-oxocyclohex-2-enoic acid methyl ester [3], was also isolated from this fraction. The structures were elucidated by chemical and nmr (COLOC, FLOCK, and selective INEPT) techniques.

Chemoenzymatic Synthesis of Idesolide from Benzoic Acid

“…3 Hydroxy ketone 2 is itself a natural product isolated from a number of species and identified by Fransworth in 1993 in n-BuOH extracts of Homalium ceylanicum. 4 In 2006 Sterk and co-workers 5 isolated hydroxy ketone 2 from Dovyalis species native to Central Africa and northern South America and confirmed the structure previously assigned by Farnsworth. This compound has also been identified as a structural component in several natural products such as the phenolic glycosides 3a-e and 4a-c ( Figure 1) isolated from fruit, leaves, bark, and twigs of Idesia polycarpa, Salix purpurea, Dovyalis abyssinica, and other species.…”

Inhibitory Activity of Phenolic Glycosides from the Fruits of Idesia polycarpa on Lipopolysaccharide-Induced Nitric Oxide Production in BV2 Microglia

“…1). The chemical structures of com-pounds 3 ± 6 were determined by comparison of their spectroscopic data with those previously reported [3], [6], [7]. The 1 Hand 13 C-NMR spectra of 1 displayed signals due to a 1,2,3-trisubstituted aromatic ring, a glucose unit and an oxymethylene, which showed close resemblances to those of idesin [3].…”

“…Two new phenolic glycosides (1 and 2) together with four known compounds, idescarpin (3), idesin (4), 1-hydroxy-6-oxocyclohex-2-enecarboxylic acid methyl ester (5) and salirepin (6), were isolated from the EtOAc fraction of I. polycarpa by several chromatographic methods (Fig. 1).…”

Antimalarial compounds from the aerial parts of Flacourtia indica (Flacourtiaceae)

“…The structures were established using NMR and mass spectrometry. Spectroscopic data were compared with reported values for Poliothrysoside (Gibbons et al, 1993) and Homaloside D (Ekabo and Farnsworth, 1993), and the identity of Pyrocatechol was confirmed by TLC with commercial sample.…”