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A new sterol, ajugasalicigenin (1), and three new sterol glycosides, ajugasaliciosides F−H (2−4), were isolated and characterized from the aerial parts of Ajuga salicifolia. Compounds 1−4 are further representatives of the stigmastane type of sterols. Their cytotoxicity against KB (HeLa) and Jurkat T cancer cells was evaluated.

Four new phenolic glycosides, β-apiofuranosyl-(1→2)-β-glucopyranosides (1−4), along with the cycloartane triterpenes 20(R),25-epoxy-3β,6α,16β,24α-tetrahydroxycycloartane (5) and 20(R),24(S)-epoxy-3β,6α,25-trihydroxycycloartan-16-one (6) were isolated from roots of Astragalus zahlbruckneri. The structure elucidation of all compounds was based on their ¹H and ¹³C NMR spectral data including 1D-TOCSY, DQF-COSY, HSQC, and HMBC experiments.

From the aerial parts of Putoria calabrica, two new flavonol triglycosides were isolated and their structures were elucidated as quercetin-3-O-[α-l-rhamnopyranosyl-(1→2)-α-l-arabinopyranoside]-7-O-β-d-glucopyranoside (1, calabricoside A) and quercetin-3-O-[4‘ ‘‘-O-caffeoyl-α-l-rhamnopyranosyl-(1→2)-α-l-arabinopyranoside]-7-O-β-d-glucopyranoside (2, calabricoside B). Additionally, seven iridoid and three lignan glycosides were isolated and characterized. Radical scavenging activities of all compounds were determined by quantifying their effects on luminol-enhanced chemiluminescence in formyl-methionyl-leucyl-phenylalanine (FMLP) stimulated human polymorphonuclear neutrophils (PMNs). Calabricoside A and B showed strong radical scavenging activity with IC50 values of 0.25 and 0.3 μM, respectively.

A new iridoid glycoside, deacetylalpinoside (2), was isolated from the aerial parts of Globularia trichosantha together with nine known iridoid glycosides:  catalpol, 10-O-benzoyl-catalpol, aucubin, asperuloside, deacetylasperuloside, asperulosidic acid, scandoside, geniposidic acid, and alpinoside (1). From the underground parts of the same plant, two new bisiridoid glycosides, globulosides A (3) and B (4); a known iridoid glycoside, globularidin; a lignan glycoside, liriodendrin; and seven phenylethanoid glycosides, arenarioside, verbascoside (= acteoside), isoacteoside, crenatoside, isocrenatoside, and trichosanthosides A and B, were isolated. Compounds 2−4 are new iridoids containing an 8,9 double bond representing a rare carbon skeleton. Their structures were established by spectroscopic methods.

Six novel cycloartane-type glycosides were isolated from the roots of Astragalus trojanus. Two of these, compounds 1 and 2, have (20R,24S)-epoxy-3β,6α,16β,25-tetrahydroxycycloartane as the aglycon, while compounds 3−6 possess 3β,6α,16β,(24S),25-pentahydroxycycloartane as the aglycon. The saccharide moieties linked to the C-3, C-6, and C-24 or C-25 positions of the aglycons in 1−6 contained either xylopyranose, glucopyranose, rhamnopyranose, or arabinopyranose units. Structure elucidation of compounds 1−6 was accomplished through the extensive use of 1D and 2D NMR techniques. In addition, a new oleanene glycoside (7) and a new tryptophan derivative (8) were also isolated and characterized.

Five phenylethanoid glycosides, crenatoside (= oraposide) (1), verbascoside (= acteoside) (2), trichosanthoside A (3), rossicaside A (4), and trichosanthoside B (5), were isolated from the aerial parts of Globularia trichosantha. Compounds 3 and 5 are new natural compounds, and their structures were established as 3,4-dihydroxy-β-phenylethoxy-O-β-d-xylopyranosyl-(1→4)-α-l-rhamnopyranosyl-(1→3)-4-O-caffeoyl-β-d-glucopyranoside and 3,4-dihydroxy-β-phenylethoxy-O-[β-d-xylopyranosyl-(1→4)-α-l-rhamnopyranosyl-(1→3)]-[β-d-xylopyranosyl-(1→6)]-4-O-caffeoyl-β-d-glucopyranoside, respectively. The structures of all compounds were established by spectral evidence. Compounds 1−5 also demonstrated scavenging properties toward the 2,2-diphenyl-1-picrylhydrazyl radical in TLC autographic assays.

(3R)-O-β-d-Glucopyranosyloxy-5-phenylvaleric acid (1), (3R)-O-β-d-glucopyranosyloxy-5-phenylvaleric acid n-butyl ester (2), and a new dihydrochalcone diglycoside 4‘-O-[β-d-glucopyranosyl-(1→6)-glucopyranosyl]oxy-2‘-hydroxy-3‘,6‘-dimethoxydihydrochalcone (3), together with six known flavonoid glycosides [kaempferol-3-O-β-d-glucopyranoside (= astragalin) (4), kaempferol-3-O-β-d-galactopyranoside (5), quercetin-3-O-β-d-glucopyranoside (= isoquercitrin) (6), quercetin-3-O-β-d-galactopyranoside (= hyperoside) (7), quercetin-3-O-(2‘ ‘-O-galloyl)-β-d-glucopyranoside (8), and quercetin-3-O-β-d-glucuronopyranoside (9)] were isolated from the aerial parts of Polygonum salicifolium. The structure elucidation of the isolated compounds was performed by spectroscopic (UV, IR, ESI-MS, 1D- and 2D-NMR), chemical (methylation, enzymatic hydrolysis, partial synthesis), and chromatographic methods (HPLC, Chiralcel OD). The flavonoid glycosides (4−9) demonstrated scavenging properties toward the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical in TLC autographic assays.

Two new iridoid glucosides, 6-O-acetylajugol (1) and 7,8-epoxy-8-epi-loganic acid (2), together with five known iridoid glucosides, galiridoside (3), ajugoside (4), 10-deoxygeniposidic acid (5), 7-deoxy-8-epi-loganic acid (6), and 8-O-acetylharpagide (7), have been isolated from the aerial parts of Leonurus persicus. Leucosceptoside A (8), eugenyl β-rutinoside (9), and kaempferol 3-O-glucoside (10) were also isolated. The structures of 1 and 2 were elucidated by extensive 1D- and 2D-NMR spectroscopy and molecular modeling. The structure of 3 was confirmed by single-crystal X-ray diffraction. Antimicrobial activity of compounds (1−10) was also evaluated against a panel of Gram-positive and Gram-negative bacteria and two strains of fungi.

Three new cycloartane-type triterpene glycosides, brachyosides A (1), B (3), and C (2), from the roots of Astragalus brachypterus and one new glycoside, cyclocephaloside II (4), from the roots of Astragalus microcephalus have been isolated together with five known saponins, astragalosides I, II, and IV, cyclocanthoside E, and cycloastragenol. The structures of the new compounds were established as 3-O-[β-d-xylopyranosyl(1→3)-β-d-xylopyranosyl-6-O-β-d-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxycycloartane (1), 3-O-β-d-xylopyranosyl-6-O-β-d-glucopyranosyl-24-O-β-d-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxycycloartane (2), 20(R),24(S)-epoxy-6-O-β-d-glucopyranosyl-3β,6α,16β,25-tetrahydroxycycloartane (3), and 20(R),24(S)-epoxy-3-O-(4‘-O-acetyl)-β-d-xylopyranosyl-6-O-β-d-glucopyranosyl-3β,6α,16β,25-tetrahydroxycycloartane (4). For the structure elucidations, 1D- and 2D-NMR experiments and FABMS were used.

Seven new labdane diterpenoids, leopersin G−L (1−4, 6−7) and 15-epi-leopersin J (5), and two known ones, 13-hydroxyballonigrinolide (8) and ballotenol (9), were isolated from the aerial parts of Leonurus persicus along with β-sitosterol and stigmasterol. The structure determinations were mainly based on 1D and 2D NMR spectra. The stereochemical configuration of ballotenol (9) was reestablished by 2D ROESY spectroscopy and by single-crystal X-ray diffraction analysis.

Six new labdane diterpenoids, leopersin C (1), 15-epi-leopersin C (2), leopersin D (3), leopersin E (4), leopersin F (5), and 7-epi-leopersin F (6) were isolated from the aerial parts of Leonurus persicus. Their structures were elucidated by extensive use of 1D and 2D homonuclear and heteronuclear shift-correlated ¹H−¹³C-NMR spectroscopic methods. Leopersin C (1) and 15-epi-leopersin C (2) were obtained as a C-15 epimeric mixture, and their structures were elucidated on this basis.

Six saponins, cyclaminorin (1), deglucocyclamin (2), cyclacoumin (3), cyclamin (4), isocyclamin (5), and mirabilin (6) were isolated from the tubers of Cyclamen mirabile. Compound 6 is a new natural compound, and its structure was established as 3-{O-β-[[β-d-xylopyranosyl-(1→2)]-[β-d-glucopyranosyl-(1→6)]-β-d-glucopyranosyl-(1→4)]-[β-d-glucopyranosyl-(1→2)]-α-l-arabinopyranosyl}-3β,16α,28-trihydroxyolean-12-en-30-oic acid (6). The structure elucidation of this compound was accomplished using both spectral and chemical methods. Antimicrobial and uterocontractile activities of the saponins were also investigated.

Four novel cycloartane-type triterpene glycosides, macrophyllosaponins A−D (1−4) were isolated from the roots of Astragalus oleifolius. By means of chemical (acetylation, alkaline hydrolysis) and spectroscopic methods (IR, 1D- and 2D-NMR, FABMS), their structures were established as 3-O-α-l-rhamnopyranosyl-24-O-(4‘‘-O-acetyl)-β-d-xylopyranosyl-1α,3β,7β,24(S),25-pentahydroxycycloartane (1), 3-O-α-l-rhamnopyranosyl-24-O-β-d-xylopyranosyl-1α,3β,7β,24(S),25-pentahydroxycycloartane (2), 3-O-α-l-rhamnopyranosyl-25-O-β-d-glucoyranosyl-1α,3β,7β,24(S),25-pentahydroxycycloartane (3), and 3-O-α-l-rhamnopyranosyl-24-O-(2-O-β-d-xylopyranosyl)-β-d-xylopyranosyl-1α,3β,7β,24(S),25-pentahydroxycycloartane (4).