Design, Synthesis, Anti-TMV Activity, and Structure-Activity Relationships of -pregnane C Steroids and Their Derivatives.

-pregnane C steroids exhibit high antiviral activity against the tobacco mosaic virus (TMV). However, the structural modification of -pregnane C steroids and the structure-activity relationship (SAR) of the modified compounds remain unevaluated. Hence, the present study investigated how variations in the original skeletons of natural -pregnane C steroids affect their antiviral activity.

Cytotoxic glutarimide-containing polyketides isolated from Streptomyces sp. JCM 4793.

Glutarimide-containing polyketides usually exhibit anti-fungi activity, which was well exampled by cycloheximide. In our work, three new polyketide structures, 12-amidestreptimidone (1), 12-carboxylstreptimidone (2) and 3-(5S,8R)-(2-amino-2-oxoethyl-2'-methoxy-2'-oxoethyl)-8,10-dimethyl-7-oxododeca-5-hydroxy-9E,11-diolefin (3) were isolated from Streptomyces sp. JCM 4793.

Two new jatrophane diterpenoids from with activity towards autophagic flux.

Nine jatrophane diterpenoids were isolated from the whole plant , including two new ones, helioscopnins A () and B (). Comprehensive spectroscopic data analysis and ECD calculations elucidated their structures, including absolute configurations. All compounds were evaluated for bioactivity towards autophagic flux by flow cytometry using HM mCherry-GFP-LC3 cells.

Quassinoids from Twigs of (Blanco) Merr and Their Anti-Parkinson's Disease Effect.

Six new C-20 and one new C-19 quassinoids, named perforalactones F-L (-), were isolated from twigs of . Spectroscopic and X-ray crystallographic experiments were conducted to identify their structures. Through oxidative degradation of perforalactone B to perforaqussin A, the biogenetic process from C-25 quassinoid to C-20 via Baeyer-Villiger oxidation was proposed.

Terpenoids from Euphorbia helioscopia and Their Cytotoxic Activities against H1975 Cells.

Three previously undescribed diterpenoids, helioscopnoids A-C, and eight known compounds were isolated from the whole plants of Euphorbia helioscopia. Their structures were established by extensive analysis of spectra and data comparison with previous literatures. Among them, compound 4 was identified as 24,24-dimethoxy-25,26,27-trinoreuphan-3β-ol with revised configurations of C-13, C-14, and C-17 (13R*, 14R*, 17R*).

Euphejolkinolide A, a new -abietane lactone from L. with promising biological activity in activating the autophagy-lysosomal pathway.

A new -abietane diterpenoid, named Euphejolkinolide A (), was isolated from the whole plant of L. Its structure, including absolute configurations, was determined by spectroscopic analyses and was corroborated by single-crystal X-ray diffraction analysis. This new compound was assessed for its activity to induce lysosome biogenesis through Lyso-Tracker Red staining, in which compound could significantly induce lysosome biogenesis.

Munronin V with 7/7/6 tricarbocyclic framework from harms inhibits tau pathology by activating autophagy.

Munronin V (1), isolated from Harms, is the first example, to the best of our knowledge, of an unprecedented 7/7/6 tricarbocyclic framework featuring an unusual A,B--limonoid ring. The structures of munronin V were established from extensive spectroscopic and electronic circular dichroism (ECD) analyses. The novel A,B- with two seven-membered lactones was formed as a result of Baeyer-Villiger oxidation.

Perforalactones D and E, two new C-20 quassinoids with potential activity to induce lysosomal biogenesis from the twigs of (Blanco) Merr.

Two new quassinoids (1 and 2) were isolated from the twigs of (Blanco) Merr. Perforalactone E (2) possesses an uncommon hexacyclic 1α,12α:5α,13α-dicyclo-9βH-picrasane skeleton. Its structure was determined based on spectroscopic data and X-ray crystallography.

Jatrophane Diterpenoids from the Seeds of Euphorbia peplus with Potential Bioactivities in Lysosomal-Autophagy Pathway.

Euphopepluanones F - K (1 - 4), four new jatrophane type diterpenoids were isolated from the seeds of Euphorbia peplus, along with eight known diterpenoids (5 - 12). Their structures were established on the basis of extensive spectroscopic analysis and X-ray crystallographic experiments. The new compounds 1 - 4 were assessed for their activities to induce lysosomal biogenesis through LysoTracker Red staining.

Diterpenoids with an unprecedented ring system from and their activities in the lysosomal-autophagy pathway.

Three novel jatrophane diterpenes, cyclojatrophanes A-C (1-3), were isolated from the seeds of Euphorbia peplus. Compounds 1-3 featured an unprecedented 5/5/5/11 tetracyclic ring system incorporating ditetrahydropyran rings. Their structures including their absolute configurations were established by extensive spectroscopic analysis, X-ray crystallographic experiments and chemical transformations.

Harpertrioate A, an A,B,D--Limonoid with Promising Biological Activity against Alzheimer's Disease from Twigs of (Blanco) Merr.

Harpertrioate A (), an A,B,D--limonoid with a rearranged ring B incorporating exocyclic C-30, was isolated from the EtOAc extract of twigs. Its structure, including absolute configurations, was determined on the basis of spectroscopic data and X-ray crystallography. This compound exhibited biological activities against Alzheimer's disease by reducing Aβ42 and Aβ40 production and shifting APP processing toward nonamyloidogenic pathway.

Macrocyclic diterpenoids from the seeds of Euphorbia peplus with potential activity in inducing lysosomal biogenesis.

The first phytochemical investigation of the seeds of Euphorbia peplus led to the isolation and characterization of five new (1-5), named euphopepluanones A-E, and five known diterpenoids (6-10). Their structures were established by extensive spectroscopic analysis and X-ray crystallographic experiments. Euphopepluanones A-E (1-3) feature a very rare 5/11/5-tricyclic skeleton, and euphopepluanones D-E (4-5) represent the first report of lathyrane type diterpenoids found in E.

Three new diterpenoids from .

Three new diterpenoids () (two abietane type diterpenoids and a paralianone type diterpenoid), together with four known compounds () were isolated from the whole plants of . Their structures were elucidated through spectroscopic analysis and physicochemical characteristics. The cytotoxic activities of compounds against five human tumour cell lines were evaluated, however, they were inactive at the concentration of 40 μM.

Diterpenes with potential treatment of vitiligo from the aerials parts of Euphorbia antiquorum L.

Six new diterpenes Euphonoids A-F including one ingenol (1), three lathyrane (2-5), one ent-abietane (6) and fifteen known derivatives (7-21) were isolated from the aerial parts of Euphorbia antiquorum L. Their structures were elucidated by physical data analysis. Compounds 1, 12, and 16 improve the melanogenesis in B16 cells in vitro.

Daphnane Diterpenoids from Trigonostemon lii and Inhibition Activities Against HIV-1.

Natural products are the important source for the discovery of more potent anti-HIV agents. In this study, six daphnane diterpenoids including three unreported structures were isolated from Trigonostemon lii, which showed significant activities against HIV-1 strains replication in the nanomolar/picomolar range. Meanwhile, these diterpenoids significantly inhibited the fusion of H9/HIV-1 IIIB cells with uninfected C8166 cells, with the EC from 1.

A new highly oxygenated abietane diterpenoid and a new lysosome generating phorbol ester from the roots of Steud.

Twenty-two diterpenoids (), including two new ones (, a tigliane-type diterpenoid and , an abietane-type diterpenoid) were isolated from the roots of Steud. Among them, compounds , , , , are isolated from this plant for the first time. Their structures were elucidated through extensive 1D, 2D NMR and the HRESIMS data.

Four new compounds from .

Four new compounds, compounds , , , , along with two known compounds , , were isolated from the methanol extract of the fruiting body of . The structures of compounds were elucidated by HRMS and NMR spectroscopic methods. The anti-inflammatory activity of the isolated compounds was evaluated.

12-Acetyloxyperforatin, a New Limonoid from .

A new A, D-seco limonoid, named 12-acetyloxyperforatin (), along with three known ones, were isolated from the leaves of . Their structures were elucidated on the basis of spectroscopic analysis, including extensive NMR techniques and computational modelling. These compounds showed no inhibitory activity against the 11-HSD1 enzyme.

Cytotoxic indole alkaloids from Melodinus khasianus and Melodinus tenuicaudatus.

Four new indole alkaloids, melodinusines A-D (1, 2, 6, and 7), along with 26 known indole alkaloids, were isolated from Melodinus tenuicaudatus and Melodinus khasianus (Melodinus genus). Among them, 1 and 2 are aspidospermine-aspidospermine-type bisindole alkaloids while 7 is a novel melodinus-type alkaloid. Their structures were established on the basis of comprehensive spectroscopic data analysis and the structure of 7 was further confirmed by single-crystal X-ray diffraction analysis.

Identification of Ingol and Rhamnofolane Diterpenoids from Euphorbia resinifera and Their Abilities to Induce Lysosomal Biosynthesis.

The phytochemical study of Euphorbia resinifera afforded 18 structurally diverse diterpenoids, including 14 new ingol-type diterpenoids, euphorblins A-N (1-14), a new rhamnofolane diterpenoid, euphorblin O (15), and three known analogues (16-18). The structures of these compounds were deduced using 2D NMR spectroscopy and NOE experiments. The structure of compound 1 was confirmed by single-crystal X-ray crystallography.

Abietane Diterpernoids from the Roots of Euphorbia ebracteolata.

A new ent-abietane diterpernoid, named ebracteolata D (1), along with 11 known analogues, was isolated from the roots of Euphorbia ebracteolata Hayata. The structure of 1 was elucidated on the basis of spectroscopic analysis and molecular modeling. Cytotoxicity of compounds 1-12 was evaluated as well as the effect on the NF-κB pathway.

Rubipodanones A-D, naphthohydroquinone dimers from the roots and rhizomes of Rubia podantha.

Four previously undescribed naphthohydroquinone dimers named rubipodanones A-D, together with 19 known quinones containing three known napthohydroquinone dimers named rubioncolin C, methyl 5-hydroxy-dinaphtho[1,2-2',3']furan-7,12-dione-6-carboxylate and rubialatin B, were isolated from the roots and rhizomes of Rubia podantha. Their structures and absolute configurations were determined mainly by NMR, X-ray diffraction, and computational methods. Rubipodanones C and D, the glycosides of rubipodanone A and a pair of C-3 epimer, are the first identified dimeric napthohydroquinone glycosides from the Rubia plants.