Four new steroidal compounds possessing a rare 13,14-seco-16,24-cycloergostane skeleton, physalin Y ( 1), physalin Z ( 2), physalin I ( 6), and physalin II ( 7), were isolated from the 80% EtOH extract of calyces from Physalis alkekengi var. franchetii together with 11 known steroids ( 3- 5 and 8- 15) and eight flavonoids ( 16- 23). The structures of the new compounds were elucidated primarily on the basis of 1D and 2D NMR and mass spectroscopic studies. The relative configuration of the 3-OH group of 3, 4, and 5 was also established or re-established. The inhibitory effects of compounds 1- 23 on nitric oxide production in lipopolysaccaride-activated macrophages were evaluated.
Ten new guaiane-type sesquiterpenes (1-10), phaeocaulisins A-J, and 18 known guaiane derivatives were isolated from rhizomes of Curcuma phaeocaulis. Their structures were established on the basis of extensive spectroscopic analyses, X-ray crystallographic analysis, and comparison with literature data. Compound 10 is the first example of a norsesquiterpene with this unusual skeleton isolated from the genus Curcuma. All of the isolated compounds were tested for inhibitory activity against LPS-induced nitric oxide production in RAW 264.7 macrophages. Compounds 1, 2, 20, and 22-24 inhibited nitric oxide production with IC50 values less than 2 μM. Preliminary structure-activity relationships for these compounds are discussed.
A new norsesquiterpene, wilfordonol E (1), and a new lignan, dipsalignan E (3), together with a known norsesquiterpene and eleven known lignans were isolated from the roots and rhizomes of Valeriana jatamansi. The structures of new compounds were determined by their NMR and HR-ESI-MS spectra. Additionally, some compounds were evaluated for their anti-influenza A virus effects.
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