Two new dammarane-type triterpenoids from the steamed roots of Panax notoginseng.

Two new dammarane-type triterpenoids, notoginsenoside SY3 (1) and notoginsenoside SY4 (2), were isolated from the steamed roots of Panax notoginseng. Their structures were determined to be 3ß, 12ß, 20(S)-trihydroxy-27-anordammar-23(24)(E)-ene-3-O-ß-D-glucopyranosyl-(1→2)-ß-D-glucopyranoside (1) and 3ß, 12ß, 20(S)-trihydroxy-25-methoxyldammar-23(24)(E)-ene-3-O-ß-D-glucopyranosyl-(1→2)-ß-D-glucopyranoside (2) by IR, HRESIMS and NMR experiments.

Paeoveitols A-E from Paeonia veitchii.

Paeoveitols A-E (1-5), involving three monoterpenes and two benzofuran constituents, were isolated from Paeonia veitchii. Their structures were determined based on extensive spectral analyses (IR, UV, MS, 1D and 2D NMR), and the absolute configuration of compound 1 was confirmed by single-crystal X-ray diffraction. By the agitating human melatonin receptor 1 (MT1) assay on HEK293 cell line in vitro, compound 4 showed weak activity with the agitation rate of 22.52% at the concentration of 1.79 mM.

[Chemical constituents of Lepidium meyenii].

To study the chemical constituents of Lepidium meyenii, the air-dried rhizome of L. meyenii was extracted with 70% EtOH. The extract was condensed to a small amount of volume and extracted with petroleum ether, EtOAc and n-BuOH, successively. The compounds were isolated and purified by column chromatography, and identified based on spectral analyses (1H-NMR, 13C-NMR, HRESIMS). Eighteen compounds were isolated from L. meyenii, including 7 alkaloids and 4 fatty acids and 7 other compounds. They were characterized as (3-hydroxybenzyl) carbamic acid(1), phenylmethanamine(2), N-benzylformamide (3), N-benzylacetamide (4), pyridin-4-ylmethanamine(5), n-(4-methoxybenzyl) aniline(6), uracil(7), succininc acid(8), decanedioic acid(9), n-hexa- decanoic acid methyl ester(10), heptanoic acid(11), solerole(12), pyromucic acid methyl ester(13), 5-hydroxymethyl-2-furancar- boxadehyde(14), 5-(methoxymethyl)-1H-pyrrole-2-carbaldehyde(15), 1,7-dihydroxy-2,3, 4-trimethoxyxanthone (16), 1,7-di- hydroxy-3,4- dimethoxy-xanthone(17), (+)-pinoresinol(18). Meanwhile, compounds 1-18 were obtained from L. neyenii for the first time.

Noreudesmane sesquiterpenoids from the leaves of Nicotiana tabacum.

Six new 14-noreudesmane sesquiterpenoids, nicotabacosides A-F (1-6), along with five known sesquiterpenoids (7-11), were isolated from the leaves of Nicotiana tabacum. The structures of compounds 1-6 were elucidated as isorishitin 3-O-ß-D-glucopyranoside (1), rishitin 3-O-ß-D-glucopyranoside (2), rishitin 2-O-ß-D-glucopyranoside (3), 1, 6-dehydro-rishitin 3-O-ß-D-glucopyranoside (4), 2-hydroxyl-ligudentatol 3-O-ß-D-glucopyranoside (5) and oxyglutinosone 3-O-ß-D-glucopyranoside (6) based on extensive spectroscopic analyses (HRESIMS, UV, IR, 1D and 2D NMR). Their absolute configurations were determined by X-ray single-crystal diffraction and comparison of their electronic circular dichroism (ECD) spectra.