Madecassic acid analogues with a five-membered A-ring and their cytotoxic activity.

The structural modification of madecassic acid focused on the contraction of the six-membered A-ring to a five-membered ring, combined with the dehydration of 6-OH to form a new double bond and formation of the esterification or amidation at C-28. The synthesised structures were identified based on the analysis of their NMR and EIS-MS data. Eighteen new madecassic acid analogues were tested for their cytotoxicity against three cancer cell lines, including human mouth carcinoma (KB), human hepatocellular carcinoma (HepG2), and human lung carcinoma (A549) using the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay.

A new sacculatane diterpenoid and a new oplopanone sesquiterpenoid from (Mont.) Trevis. collected in Sapa, Vietnam.

From the -hexane extract of the liverwort collected in Sapa (North Vietnam), a new sacculatane diterpenoid (perrottetianal E ()) and a new oplopanone sesquiterpenoid ((+)-oplopanone C ()), along with two known sesquiterpenes ( and ), and two known phaeophytins ( and ) have been isolated. Their structures were elucidated based on the analysis of NMR spectroscopic data, in combination with HR-ESIMS and the reported data. Compounds were evaluated for their cytotoxic activities against three cancer cell lines: KB (human carcinoma in the mouth), HepG2 (human hepatocellular carcinoma), and A549 (human lung carcinoma).

Cytotoxic and Anti-Inflammatory Activity of 3,19-Isopropylidene-/Arylidene-Andrographolide Analogs.

A series of 3,19-isopropylidene-/or arylidene-andrographolide analogs were synthesized and their structures were confirmed by NMR spectroscopic methodology. Twenty-five analogs were evaluated for their in vitro cytotoxic activity against HT-29, HepG2 and LNCaP cancer cell lines based on the sulforhodamine B (SRB) assay. Analog 2 f exhibited the most potent cytotoxic activity, with IC values of 11.

Synthesis, Anti-Influenza H1N1 and Anti-Dengue Activity of A-Ring Modified Oleanonic Acid Polyamine Derivatives.

A series of sixteen A-ring modified (2,3-indolo-, 2-benzylidene) oleanonic acid derivatives, holding some cyclic amines, linear polyamines and benzylaminocarboxamides at C28, has been synthesized and screened for antiviral activity against influenza A/PuertoRico/8/34 (H1N1) and Dengue virus serotypes of DENV-1, -2, -3, -4. It was found that 28-homopiperazine and 3--phthalyl amides of oleanonic acid demonstrated high potency with selectivity index SI 27 (IC 21 μM) and 42 (IC 12 μM). Oleanonic acid aminoethylpiperazine amide and C-azepano-erythrodiol appeared to be the most effective compounds against DENV-1 (ICs 67 and 107 μM) and -2 (ICs 86 and 68 μM correspondingly) serotypes.

Newly synthesised oxime and lactone derivatives from dipterocarpol as anti-diabetic inhibitors: experimental bioassay-based evidence and theoretical computation-based prediction.

-derived products are expected to exhibit anti-diabetes properties. Natural dipterocarpol (1) was isolated from collected in Quang Nam province, Vietnam; afterwards, 20 derivatives including 13 oxime esters (2 and 3a-3m) and 7 lactones (4, 5, 6a-6e) were semi-synthesised. Their inhibitory effects towards diabetes-related proteins were investigated experimentally (α-glucosidase) and computationally (3W37, 3AJ7, and PTP1B).

Isolation, semi-synthesis, docking-based prediction, and bioassay-based activity of iridoids: new catalpol derivatives as glucosidase inhibitors.

iridoids are promising anti-diabetic inhibitors towards α-glucosidase protein (PDB-3W37) and oligo-1,6-glucosidase protein (PDB-3AJ7). Five catalpol iridoids (1, 2, 10, 13, 14) were isolated from mangrove plant , and their derivatives (3, 4, 5, 6, 7, 8, 9, 11, 12, 15) were obtained from reduction, acetylation, -alkylation, acetonisation, or hydrolysation starting from naturally isolated compounds. They were identified by spectral methods such as IR, MS, and 1D and 2D NMR.

Chevalierinol A and B, two new neolignan sesquiterpenoids from .

Two new neolignan sesquiterpenoids, chevalierinol A (1) and chevalierinol B (2), were isolated from the ethyl acetate extract of leaves, together with twelve known compounds (3-14). Their structures were elucidated by analysis of spectroscopic data including 1D, 2D and mass spectra and compared with the reported data. Compounds , , , , , were evaluated for their inhibitory effect against lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.

Two new prenylated isoflavones from Maclura cochinchinensis collected in Hoa Binh province Vietnam.

Two new prenylisoflavones, 3',4',5-trihydroxy-8-prenyl-dihydrofuran[2″,3″:7,6]isoflavone (1) and 4',5-dihydroxy-8-prenyl-dihydrofuran[2″,3″:7,6]isoflavone (2), along with five known prenylisoflavones (3-7), benzylalcohol-4-O-β-d-glucoside (8) and two cinnamic acid esters (9, 10) were isolated from the leaves of Maclura cochinchinensis (Cudrania cochinchinensis). Their structures were elucidated by analysis of NMR (H-, C-NMR, HSQC, HMBC), MS spectra and comparison with the published data. Compounds 4-10 were the first time isolated from this species.

New cycloartanes and new iridoids from Dolichandrone spathacea collected in the mangrove forest of Soc Trang province, Vietnam.

Two new cycloartanes, named dolichandrone A (1) and dolichandrone B (2), as well as two new iridoids, named [6-O-[(E)-4-methoxycinnamoyl]-1β-hydroxy-dihydrocatalpolgenin (3) and 6-O-[(E)-4-methoxycinnamoyl]-1α-hydroxy-dihydrocatalpolgenin (4), together with four known iridoids (5-8), were isolated from the leaves and barks of Dolichandrone spathacea. Their structures were elucidated by means of extensive analysis of their HRESIMS, 1D and 2D NMR spectroscopic data. All of these compounds have been isolated for the first time from this plant.