Racemic immunosuppressive seco-aporphine derivatives from Thalictrum wangii

Ormosianines A-P, Structurally Diverse Quinolizidine Alkaloids with AChE Inhibitory Effects from Ormosia yunnanensis

Sixteen new quinolizidine alkaloids (QAs), named ormosianines A-P (1-16), and 18 known congeners (17-34) were isolated from the stems and leaves of Ormosia yunnanensis. The structures were elucidated based on spectroscopic analyses and electron circular dichroism (ECD) calculations. Structurally, ormosianines A (1) and B (2) are the first examples of cytisine and Ormosia-type alkaloids with the cleavage of the piperidine ring. Results of the acetylcholinesterase (AChE) inhibitory assay revealed that the pentacycline Ormosia-type QAs, including 1, 16, 24, and 27-29, are good AChE inhibitors. Ormosianine A (1) exhibited more potent AChE inhibitory activity with an IC50 value of 1.55 μM. Molecular docking revealed that 1 might bind to the protein 1DX4, forming two hydrogen bonds with residues SER-238 and HIS-480.

Ethnobotany, botany, phytochemistry and ethnopharmacology of the genus Thalictrum L. (Ranunculaceae): A review

ETHNOPHARMACOLOGICAL RELEVANCE

Thalictrum (Ranunculaceae) is known for its important alkaloids which have been reported to exhibit various pharmacological activities, viz. antitumor, antimicrobial, antitussive, antiamebic, hypotensive effects, HIV antiviral, etc. Throughout the world, the plant has been used as a tonic, purgative, stimulant, aperient and is utilized in various systems of medicine in the treatment of various ailments like snake bite, jaundice, rheumatism, stomachache, wounds, swellings, uterine tumors, paralysis, joints pain, nervous disorders, toothache, diarrhea, piles, fever, peptic ulcer, ophthalmic, headache, diuretic, dyspepsia, convalescence, etc. AIMS OF THIS REVIEW: To bring together all the information regarding the botany, phytochemistry, ethnobotany and ethnopharmacology of Thalictrum and identify the gaps in the existing studies so that full medicinal potential of the genus can be realized.

METHODS

Available literature on botany, geography, traditional uses, phytochemicals, and pharmacology was gathered by referring to library and electronic searches in PubMed, Science Direct, Google Scholar, relevant journals and books.

RESULTS

A variety of phytochemicals like alkaloids, essential oils, glycosides, phenols and terpenoids have been reported from Thalictrum species. Alkaloids are the most dominant diverse group with 178 different types. The crude extracts and isolates exhibit a gamut of pharmacological activities, namely anticancer, antimalarial, antioxidant, antipyretic, anti-tumor, ant-influenza virus, contraceptive and immunosuppressive. Northalrugosidine, an alkaloid from T. alpinum shows in vivo antileishmanial activity. So far, cytotoxic effects of only three Thalictrum species, viz. T. dasycarpum, T. foliolosum and T. simplex have been reported. Thl isolated from T. simplex is found to be 50% toxic (CC50%) at the concentration ranging from 53 to 95 μM.

CONCLUSIONS

Thalictrum has tremendous medicinal values used in many traditional systems of medicine. It has multiple chemical components and still there is scope to explore more. Multiple chemical constituents and its utilization signify its high demand in the drug markets or pharmaceutical companies. In depth phytochemical studies along with in vitro studies with respect to their active principles can help in tapping the full medicinal potential of the genus.

Structurally diverse biflavonoids from the fruits of Citrus medica L. var. sarcodactylis Swingle and their hypolipidemic and immunosuppressive activities

The fruit of Citrus medica L. var. sarcodactylis Swingle is not only used as a traditional medicinal plant, but also served as a delicious food. Six new (3'→7″)-biflavonoids (1-6), and twelve known biflavonoid derivatives (7-18) were isolated and characterized from the fruits of C. medica L. var. sarcodactylis Swingle for the first time. Their structures were determined by extensive and comprehensive analyzing NMR, HR-ESI-MS, UV, and IR spectral data coupled with the data described in the literature. Compounds (1-18) were evaluated for their hypolipidemic activities with Orlistat as the positive control, and assayed for their immunosuppressive activities with Dexamethasone as the positive control, respectively. Among them, compounds (1-3) exhibited moderate inhibition of pancreatic lipase activity by inhibiting 68.56 ± 1.40%, 56.18 ± 1.57%, 53.51 ± 1.59% of pancreatic lipase activities at the concentration of 100 μM, respectively. Compounds (4-6) and 8 showed potent immunosuppressive activities with the IC₅₀ values from 16.83 ± 1.32 to 50.90 ± 1.79 μM. The plausible biogenetic pathway and preliminary structure activity relationship of the selected compounds were scientifically summarized and discussed in this study.

Cytotoxic triterpenoid saponins from Thalictrum atriplex

Two new cycloartane glycosides, cycloatriosides A and B (1-2), and a new oleanolic acid glycoside, thaliatrioside A (3), along with 7 known triterpenoids (4-10) were isolated from Thalictrum atriplex. The structures of the new compounds were established as 3-O-β-D-galactopyranosyl (20S, 24 R)-3β,16β,25,29-tetrahydroxy-20,24-epoxycycloartane-29-O-β-D-glucopyranoside (1), 3-O-β-D-glucopyranosyl-(1→2)-α-arabinopyranosyl-3β,22ξ,30-trihydroxycycloart-24-en-21-oic acid α-L-arabinopyranosyl-(1→6)-β-D-glucopyranoside (2) and 3-O-[α-L-rhamnopyranosyl-(1→3)-β-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl]-oleanolic acid 28-O-β-D-glucopyranosyl ester (3) on the basis of extensive NMR and HR-ESI-MS analyses, along with acid hydrolysis. Their cytotoxic activities against human lung cancer cells A549 and human breast cancer cells MDA-MB-231 were evaluated using MTT method. Compound 9 showed cytotoxicity against MDA-MB-231 cell line with the IC₅₀ value of 72.53 ± 1.08 μM.

Structurally Diverse Flavonolignans with Immunosuppressive and Neuroprotective Activities from the Fruits of Hippophae rhamnoides L

The fruit of Hippophae rhamnoides L. has been used for centuries in Europe and Asia as a food with high nutritional and medicinal values. In this study, a bioactivity-guided phytochemical investigation of H. rhamnoides L. has resulted in four new dimethylallylated flavonolignans (1-4), four new isopropylpentenone-flavonolignan heterodimers (5-8), two new geranylated flavonolignans (9 and 10), and 14 known flavonolignan derivatives (11-24); they were elucidated by their spectrometric and spectroscopic methods, including HR-ESI-MS, NMR, IR, and UV from the fruit of H. rhamnoides L. for the first time. Among them, compounds 2, 5, 6, 20, and 21 showed potent immunosuppressive activities with IC₅₀ values from 19.42 ± 3.91 to 48.05 ± 12.56 μM. Meanwhile, compounds 1, 4, 11, 12, and 13 showed moderate neuroprotective activities, which increased the cell survival rate from 50.30 ± 4.24% for the model group to 71.63 ± 3.04%, 70.02 ± 4.13%, 61.53 ± 5.93%, 61.08 ± 3.58%, and 65.68 ± 4.88% at 10 μM, respectively. The hypothetical biogenetic pathway and preliminary structure-activity relationship were found and discussed scientifically.

Cytotoxic androstane derivatives from Sarcococca ruscifolia

Sarcorusones A-D (1-4), four new androstane (C19-steroid) derivatives were characterized from Sarcococca ruscifolia along with five known compounds. Their structures were elucidated on the basis of extensive MS and NMR spectroscopic analysis. All the new structures share common 14-hydroxyl and 17-ketone functional groups, and compounds 2-4 feature a seneciamide group connecting to C-3 position. The inhibitory activities of all the isolates against melanoma cell B16F10 and lung cancer cell H1299 were evaluated, and compounds 2, 3, 5, and 6 exhibited moderate cytotoxic activities against B16F10 and H1299 cell lines with IC₅₀ values 2.7-8.0 μM.