[Two new glycosides from Hypericum elatoides].

The column chromatography with silica gel, reversed-phase C_(18), and Sephadex LH-20 was employed to separate the methanol extract of the aerial parts of Hypericum elatoides. The compounds were identified by the comprehensive analysis of IR, NMR, and MS data as methyl 8-O-ß-D-glucopyranosyl-(Z)-5-octenoate(1), methyl 3-O-ß-D-glucopyranosyl-4-methylhexanoate(2), byzantionoside B(3), 9-epi-blumenol C glucoside(4), corchoionoside C(5),(6S,9R)-roseoside(6), cis-p-coumaric acid 4-O-ß-D-glucopyranoside(7), trans-p-coumaric acid 4-O-ß-D-glucopyranoside(8), methyl 3-(4-hydroxyphenyl)propanoate(9),(E)-chlorogenic acid methyl ester(10), quercetin-3-O-ß-D-glucopyranoside(11), ß-sitosterol(12), stigmasterol(13), stigmast-4-en-3-one(14), ß-amyrin(15), daucosterol(16), sitoindoside Ⅰ(17), oleic acid(18), methyl α-linolenate(19), trilinolein(20), and cassipourol(21). Among them, compounds 1 and 2 were identified as new glycosides and named hyperelatosides G and H. Compounds 3-5, 7-9, 17, and 20-21 were isolated from the genus Hypericum for the first time. The remaining compounds were isolated from H. elatoides for the first time. The results of biological assays revealed that compound 11 exhibited significant anti-neuroinflammatory activity, and compounds 1, 3, and 19 displayed certain neuroprotective effects.

Discovery from Hypericum elatoides and synthesis of hyperelanitriles as α-aminopropionitrile-containing polycyclic polyprenylated acylphloroglucinols.

The search for lead compounds with anti-neuroinflammatory activity from structurally 'optimized' natural products is a crucial and promising strategy in the quest to discover safe and efficacious agents for treating neurodegenerative diseases. A phytochemical investigation on the aerial portions of Hypericum elatoides led to the isolation of five nitrogenous polycyclic polyprenylated acylphloroglucinols (PPAPs), hyperelanitriles A-D (1-4) and hyperelamine A (5). Their structures were determined by spectroscopic analysis, ECD and NMR calculations, and X-ray crystallography. To the best of our knowledge, compounds 1-4 represent the first examples of acylphloroglucinols featuring an α-aminonitrile moiety, while 5 is a rare enamine-containing PPAP. Further, the synthesis of these naturally occurring PPAP-based nitriles or amines was accomplished. Compound 5 exhibited inhibitory activity against LPS-activated NO production in BV-2 cells, potentially through the suppression of TLR-4/NF-κB signaling. Here we show the isolation, structural elucidation, synthesis, and bioactive evaluation of compounds 1-5.