Biomedical subjects
Publications and source records attributed to Ning-Hua Tan.
Human cathepsin K, matrix metalloproteinase 9, and alpha(V)beta(3) integrin are the key regulators in osteoclast-mediated bone resorption. In this paper, we found natural inhibitors 1-10 for them by enzyme inhibition assays. Inhibitors 1-7, 8-9, and 10 are novel inhibitors of human cathepsin K, matrix metalloproteinase 9, and alpha(V)beta(3), respectively.
Six new norlignans, named sequosempervirins B-G (1-6), together with three known norlignans, agatharesinol (7), agatharesinol acetonide (8), and sugiresinol (9), were isolated from the branches and leaves of Sequoia sempervirens. Their structures were determined mainly by high-resolution mass spectroscopy (HR-MS), and various 1D- and 2D-NMR methods, as well as, in the case of 1, by means of X-ray diffraction. Compound 8 showed anticancer activity towards the A549 non-small-cell lung-cancer cell line (IC50 = 27.1 microM). The acetone extract of S. sempervirens was found to be antifungal towards Candida glabrata (IC50 = 15.98 microg/ml), and both the acetone and MeOH extracts inhibited the proteolytic activity of cathepsin B (IC50 = 4.58 and 5.49 microg/ml, resp.).
A new chlorine-containing phenoloid, named capitulatin A, has been isolated from the rhizomes of Curculigo capitulata. Its structure was established as 2,4-dichloro-3-methyl-5-hydroxy-6-methoxylphenol-beta-D-xylopyranosyl (1 --> 6)-beta-D-glucopyranoside (1) on the basis of the spectral data and chemical evidence.
Five novel alkaloids, brachystemidines A-E (1-5), were isolated from the roots of Brachystemma calycinum. Their structures were established by spectral data, especially by 1D and 2D NMR techniques. The crystal structure of brachystemidine D was determined via X-ray diffraction analysis.
The chemical investigation of Cucubalus baccifer L. afforded three new norsesquiterpenoids, cucubalol, cucubalactone and drummondol-11-O-beta-D-glucopyranoside together with two known related compounds, drummondol and 5,7[E]-megastigmadiene-3 beta,4 alpha,9 xi-triol. Their structures were established based on spectral and chemical evidence. No activity was observed in anti-cancer (CDC25), antibacterial (PEPT) and antifungal (YNG) assays.
From the branches and leaves of Cupressus duclouxiana two new lignan glycosides named cupressoside A (1) and cupressoside B (2), together with matairesinoside (3), dihydrodehydrodiconiferyl alcohol (4), dihydrodehydrodiconiferyl alcohol-9-O-alpha-L-rhamnopyranoside (5), dihydrodehydrodiconiferyl alcohol-4-O-alpha-L-rhamnopyranoside (6), ( - )-isolariciresinol (7) and ( - )-isolariciresinol-9-O-beta-D-xylopyranoside (8), were isolated. The structures of these compounds were determined on the basis of their HR-FAB-MS, IR, UV, 1H and 13C NMR (DEPT), and 2D NMR (HMQC, HMBC, COSY, NOESY) spectral data.