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Two new iridoid glycosides (1 and 2), together with the known compounds barlerin (3) and verbascoside (4), were isolated from Barleria prionitis. The new iridoid glycosides were determined to be 6-O-trans-p-coumaroyl-8-O-acetylshanzhiside methyl ester (1) and its cis isomer (2) by using spectroscopic, especially 2D NMR, data. A 3:1 mixture of 1 and 2 was shown to have potent in vitro activity against respiratory syncytial virus (EC50 2.46 microgram/mL, IC50 42.2 microgram/mL).

Three new phenylpropanoid glycosides, named luteoside A (3), luteoside B (4), and luteoside C (5), were isolated together with the known compounds verbascoside (1) and isoverbascoside (2) from the roots of the medicinal plant Markhamia lutea. The structures of the new compounds were determined to be 1-O-(3, 4-dihydroxyphenyl)ethyl beta-D-apiofuranosyl(1-->2)-alpha-l-rhamnopyranosyl(1-->3)-4-O- caffeo yl-6-acetyl-beta-d-glucopyranoside, 1-O-(3,4-dihydroxyphenyl)ethyl beta-d-apiofuranosyl(1-->2)-alpha-l-rhamnopyranosyl(1-->3)-6-O- caffeo yl-beta-d-glucopyranoside, and 1-O-(3,4-dihydroxyphenyl)ethyl beta-D-apiofuranosyl(1-->2)-alpha-l-rhamnopyranosyl(1-->3)-6-O- ferulo yl-beta-d-glucopyranoside, respectively, on the basis of chemical and spectroscopic data. All five phenylpropanoid glycosides exhibited potent in vitro activity against respiratory syncytial virus.

Two new naphthoquinones, rhinacanthin-C (1) and rhinacanthin-D (2), exhibit inhibitory activity against cytomegalovirus (CMV), with EC50 values of 0.02 and 0.22 microgram/mL, respectively, against human CMV. They were isolated from the medicinal plant Rhinacanthus nasutus (Acanthaceae). The structures of the compounds were determined by analysis of their spectroscopic data, in particular, 2D NMR.