(E)-1-(2-Hy­droxy-4,6-dimeth­oxy­phen­yl)-3-(4-meth­oxy­phen­yl)prop-2-en-1-one from Kaempferia rotunda Val.

The planar –CH=CHC(=O)– fragment (r.m.s. deviation = 0.074 Å) in the title compound, C18H18O5, connects the planar hy­droxy­dimeth­oxy­phenyl (r.m.s. deviation = 0.039 Å) and meth­oxy­lphenyl (r.m.s. deviation = 0.021 Å) parts. The central fragment forms a dihedral angle of 13.7 (1)° with the hy­droxy­dimeth­oxy­phenyl part and 32.0 (1)° with the meth­oxy­phenyl part. The hy­droxy group forms an intra­molecular hydrogen bond to the carbonyl O atom

Flavokavain B from the rhizome of Alpinia mutica Roxb

The title compound [systematic name: (E)-1-(2-hydroxy-4,6-dimethoxyphenyl)-3-phenylprop-2-en-1-one], C17H16O4, has an aromatic ring at both ends of the –CH= CH–C(=O)– fragment with the –CH=CH– bond in a trans configuration. The phenyl ring is nearly coplanar with this fragment [dihedral angle 4.8 (3) °] as is the hy­droxy­ldimeth­oxy­lphenyl unit [dihedral angle 6.3 (3) °]. The hy­droxy group is the donor in an intra­molecular hydrogen bond to the double-bonded O atom

Rauniticine-allo-oxindole B methanol monosolvate

The title penta­cyclic oxindole alkadoid, isolated from Uncaria longiflora, crystallizes as a methanol solvate, C20H22N2O4·CH4O. The five-membered ring comprising the indole fused ring is nearly planar [maximum atomic deviation = 0.031 (2) Å], whereas the five-membered ring having alphatic C atoms adopts an envelope shape (with the tertiary N atom representing the flap). The six-membered ring that shares an N atom with the envelope-shaped ring adopts a chair shape; the six-membered ring having an O atom is sofa-shaped. The carb­oxy­lic acid group acts as a hydrogen-bond donor to a methanol mol­ecule; this, in turn, acts as a hydrogen-bond donor to the double-bond carboxyl O atom of an adjacent mol­ecule, generating a chain. Adjacent chains are linked by N—H⋯O hydrogen bonds, forming a layer motif

3-Acetyl-5-hy­droxy-2-methyl­anthra[1,2-b]furan-6,11-dione

The asymmetric unit of the title compound, C19H12O5, contains two independent mol­ecules, both slightly buckled along an axis passing through the C=O bonds of the anthraquinone ring system (r.m.s. deviation of non-H atoms = 0.082 and 0.148 Å): the benzene rings are twisted to each other by 4.3 (3)°in one mol­ecule and 10.6(3)° in the other. In both mol­ecules, the hy­droxy group forms an intra­molecular O—H⋯O hydrogen bond. The two independent mol­ecules inter­act by π–π stacking with a centroid–centroid distance of 3.539 (2) Å between hy­droxy­benzene rings of adjacent mol­ecules

High-performance liquid chromatography quadrupole time-of-flight mass spectrometry (HPLC-QTOFMS) analysis on the ethanol:water (80:20) extract of lawsonia inermis leaves

Lawsonia inermis (Henna), (Lythraceae), contains a high amount of phenolic compounds which could activate antioxidants to help reduce free radicals. In this study, the compound content found in the ethanol:water (80:20) extract of local Lawsonia inermis was determined using HPLC-QTOFMS. The 1 H-NMR results were used to determine the peak that exists for the group compounds. Chromatographic peaks were detected and integrated by the MassHunter Acquisition B.07.00 for the Agilent TOF and QTOF and MassHunter Qualitative Analysis B.07.00. The ethanol:water (80:20) extract of L. inermis have shown, predominantly, the presence of phenolic compounds (coumarins, flavonoids, naphthalene, and gallic acid) which are highly glycosylated. The presence of compounds such as apiin, lawsone, apigenin, luteolin, cosmosiin, and p-coumaric acid were also found

Lancifoliaine, a New Bisbenzylisoquinoline from the Bark of Litsea lancifolia

A new bisbenzylisoquinoline, lancifoliaine (1), together with seven known alkaloids – N-allyllaurolitsine (2), reticuline (3), actinodaphnine, norboldine, pallidine, cassythicine and boldine – were isolated from the stem bark of Litsea lancifolia (Lauraceae). In addition to that of lancifoliaine, complete 13C-NMR data of N-allyl-laurolitsine (2) was also reported. The alkaloidal structures were elucidated by means of high field 1D- and 2D-NMR IR, UV, and LCMS-IT-TOF spectral data. N-Allyllaurolitsine (2) showed a moderate vasorelaxant activity on isolated rat aorta

Antidiabetic and Antioxidant Properties of Alkaloids from Catharanthus roseus (L.) G. Don

Abstract: Catharanthus roseus (L.) G. Don is a herbal plant traditionally used by local populations in India, South Africa, China and Malaysia to treat diabetes. The present study reports the in vitro antioxidant and antidiabetic activities of the major alkaloids isolated from Catharanthus roseus (L.) G. Don leaves extract. Four alkaloids—vindoline I, vindolidine II, vindolicine III and vindolinine IV—were isolated and identified from the dichloromethane extract (DE) of this plant’s leaves. DE and compounds I–III were not cytotoxic towards pancreatic β-TC6 cells at the highest dosage tested (25.0 μg/mL). All four alkaloids induced relatively high glucose uptake in pancreatic β-TC6 or myoblast C2C12 cells, with III showing the highest activity. In addition, compounds II–IV demonstrated good protein tyrosine phosphatase-1B (PTP-1B) inhibition activity, implying their therapeutic potential against type 2 diabetes. III showed the highest antioxidant potential in ORAC and DPPH assays and it also alleviated H2O2-induced oxidative damage in β-TC6 cells at 12.5 μg/mL and 25.0 μg/mL

Dengue protease inhibition activity of selected malaysian medicinal herbs

Dengue fever is one of major health problem around the world including Malaysia. It is caused by the arthropode-borne flavivirus and transmitted by the bite of the Aedes aegypti or Aedes albopictus mosquito infected with one of the four dengue virus serotypes (DENV-1, DENV-2, DENV-3, or DENV-4). In this study, a screening exercise of various Malaysian medicinal plants showed that the extracts of Lawsonia inermis, Dryobalanops aromatica, Punica granatum, Zizyphus jujuba Lam. and Zingiber zerumbet exhibited potent inhibitory activity against NS2B-NS3 serine protease. The methanol extracts of Dryobalanops aromatica showed inhibition of 99.70 % at concentration of 200 µg/mL with IC50 value of 0.30 ± 0.16 µg/mL. © 2019, Malaysian Society for Parasitology. All rights reserved