Synthesis and in†vitro Anti-Inflammatory Activity of Novel Dendrobine Amide/Sulfonamide Derivatives.

A traditional Chinese medicine ingredient, dendrobine, has been demonstrated to have anti-inflammatory properties. However, due to its poor anti-inflammatory properties, its clinical use is limited. Consequently, we have designed and synthesized 32 new amide/sulfonamide dendrobine derivatives and screened their anti-inflammatory activities in vitro. Experiments showed that nitric oxide (NO) generation in lipopolysaccharide (LPS)-induced RAW264.7 cells was strongly reduced by derivative 14, with an IC50 of 2.96 µM. Western blot research revealed that 14 decreased the concentration-dependent expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (INOS). Molecular docking was used to predict the binding of the inflammation-associated proteins COX-2 and INOS to compound 14.

Structurally Diverse Coumarins from Peucedanum praeruptorum and their Anti-Inflammatory Activities via NF-κB Signaling Pathway.

The phytochemical study of Peucedanum praeruptorum led to the isolation of twenty-five coumarins (1-25). Of which, (±) praeruptol A (±1), one pair of previous undescribed seco-coumarin enantiomers were obtained. Their structures were established according to HR-ESI-MS, NMR, X-ray single crystal diffraction analysis, as well as ECD calculation. All compounds were tested for anti-inflammatory activity in the RAW264.7 macrophage model, and eight compounds (7-10, and 13-16) exhibited significant inhibitory effects with IC50 values ranging from 9.48 to 34.66 µM. Among them, compound 7 showed the strongest inhibitory effect, which significantly suppressed the production of IL-6, IL-1ß, and TNF-α, as well as iNOS and COX-2 in a concentration-dependent manner. Further investigated results showed that compound 7 exerted an anti-inflammatory effect via the NF-κB signaling pathway.

Limonoids from the Branches and Leaves of Aglaia lawii and Their Cytotoxic Activities.

Three undescribed limonoids (1-3), named aglaians G-I, and one new natural product azedaralide (4), together with nine known analogues (5-13) were isolated from the branches and leaves of Aglaia lawii by RP C18 column, silica gel column, Sephadex LH-20 column chromatography and preparative HPLC. The structures of the new compounds were elucidated by IR, HRESIMS, 1D, 2D NMR, electronic circular dichroism (ECD) calculations and X-ray crystallography diffraction analysis. The results of bioassay showed that the compound 12 exhibited potential inhibitory activity against six human tumor cell lines (MDA-MB-231, MCF-7, Ln-cap, A549, HeLa and HepG-2) with IC50 values as 8.0-18.6 µM.

Unusual triterpenoids and steroids from Cipadessa baccifera and their biological activities.

Five undescribed triterpenoids and steroids (1-5), as well as ten known compounds, were purified from the branches and leaves of Cipadessa baccifera. Notably, 1 and 2 are rare cipadesin-type limonoids with an unusual 8,30-epoxide ring and 1,8-ether linkage, respectively. Compound 5 possessed pregnane steroid skeleton with an uncommon 5/6/6/6/5-fused ring system. Their structures were constructed by extensive spectroscopic analysis (NMR, IR, UV, and HRESIMS), and their absolute configurations were confirmed by ECD calculations and quantum chemical calculations. All the isolates were in vitro assayed for their antimicrobial potentials against 6 pathogenic microorganisms and antiproliferation activities against five human cancer cell lines. As a result, compounds 5, 12, 13, and 14 exhibited moderate antibacterial activities (MIC: 25-50 µg/mL). Moreover, 5 showed cytotoxicity against five cancer cell lines with IC50 values ranging from 8.0 to 19.9 µM.

Novel flavonolignans from the roots of Indigofera stachyodes.

Two pairs of new enantiomeric flavonolignans, ±stachyols A and B (±1 and ± 2), along with two novel isoflavanelignans, stachyols C and D (3 and 4) were isolated from the roots of Indigofera stachyodes. Their chemical structures and absolute configurations were determined using nuclear magnetic resonance and comparison of experimental and theoretical electronic circular dichroism (ECD) spectra, as well as quantum chemical calculations. Of those compounds, 1 and 2 represented the first examples of flavonolignans with 5-deoxyflavonoids adduct phenylpropanoids. Moreover, 3 and 4 possess an unprecedented skeleton with isoflavanes adduct phenylpropanoids. The antioxidant activity was evaluated for all compounds in terms of ABTS+ and DPPH bioassays. Compounds 3 and 4 exhibited significant radical-scavenging activity in the ABTS+ assay, with IC50 values of 15.15 and 5.83 µM, respectively.

Cipacinerasins A-K, structurally diverse limonoids from Cipadessa baccifera.

Eleven undescribed limonoids, cipacinerasins A-K, involving of four diverse carbon skeletal types, along with fifteen known analogues, were isolated from the branches and leaves of Cipadessa baccifera. Within them, cipacinerasins A and B feature a rearranged tetrahydropyranyl ring B formed between C-8 and C-30, are unusual miscellaneous-type limonoids. Cipacinerasins E and F are rare trijugin-type limonoids, of which the D-ring δ-lactone is cleaved. Their structures were elucidated on the basis of extensive spectroscopic data (HRESIMS, NMR, UV and IR), electronic circular dichroism (ECD) calculations, and single-crystal X-ray diffraction analysis. All compounds were evaluated in vitro cytotoxicity against five human tumor cell lines (K562, HeLa, PC3, LN-Cap and Hell), and cipacinerasin E showed moderate antitumor activity with IC50 values ranging from 8.0 to 24.8 µM.

Photo-Fenton effect of 4-chlorophenol in ice.

The photoconversion of 4-chlorophenol (4-CP) in a simulated sunlight-Fenton system was investigated in ice and aqueous solution. It was found that the hydroxyl radical (OH) had an important effect on the photoconversion of 4-CP in both phases, but the effects of Cl(-), SO4(2-), NO3(-), and HCO3(-) were different. In aqueous solution, the photoconversion efficiency of 4-CP was proportional to the OH concentration, and hence, Cl(-) and HCO3(-) as OH scavengers prohibited the photoconversion; SO4(2-) had little effect; NO3(-) promoted the process under certain conditions owing to OH being generated by the photolysis of NO3(-). In ice, however, the photoconversion efficiency of 4-CP was not proportional to the concentration of OH. The photoconversion efficiency of 4-CP increased with increasing concentrations of all ions, although the OH remained almost constant, only increasing or decreasing slightly. This provides new evidence for the presence of a quasi-liquid layer (QLL). Hydroxylation products were detected in both phases. All photoproducts in aqueous solution contained only a single benzene ring, whereas in ice, dimers were also detected.