Iridoid and phenylethanoid glycosides from Heterophragma sulfureum

•An iridoid glycoside with α-d-galactopyranose was isolated from Heterophragma sulfureum.•A new phenylethanoid glycoside was isolated from H. sulfureum.•This is the first phytochemical study on H. sulfureum.

An unusual iridoid diglycoside (specioside 6′-O-α-d-galactopyranoside) and a new phenylethanoid triglycoside (heterophragmoside) were isolated from the leaves and branches of Heterophragma sulfureum together with specioside, verminoside, 6-trans-feruloylcatapol, stereospermoside, (−)-lyoniresinol 3α-O-β-d-glucopyranoside, (+)-lyoniresinol 3α-O-β-d-glucopyranoside, (−)-5′-methoxyisolariciresinol 3α-O-β-d-glucopyranoside, (+)-5′-methoxyisolariciresinol 3α-O-β-d-glucopyranoside, and dehydroconiferyl 4-O-β-d-glucopyranoside. The structural elucidations were based on analyses of chemical and spectroscopic data.

Graphical abstractAn unusual iridoid diglycoside, specioside 6′-O-α-d-galactopyranoside and a new phenylethanoid triglycoside, heterophragmoside were isolated from Heterophragma sulfureum.Download full-size image