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Cephalotanes are a rare class of diterpenoids occurring exclusively in Cephalotaxus plants. The intriguing structures and promising biological activities for this unique compound class prompt us to investigate C. fortunei var. alpina and C. sinensis, leading to the isolation of six undescribed cephalotane-type diterpenoids and/or norditerpenoids, ceforloids A-F (1-6). Their structures were elucidated by comprehensive analysis of spectroscopic data, including ECD and single-crystal X-ray diffraction studies, as well as quantum chemical calculations. Compound 1 possesses an unprecedented norditerpenoid skeleton featuring an unusual acetophenone moiety, and originated putatively from a disparate biogenetic pathway. Compounds 4 and 5 incorporate a unique 12,13-p-hydroxybenzylidene acetal motif. Compound 6 is a rare cephalotane-type diterpenoid glycoside. Immunosuppressive assays showed that compounds 2 and 6 exhibited mild suppressive activity against the activated T and B lymphocytes proliferation. These findings not only expanded the structural diversity of this small group of diterpenoids, but also explored their potential as novel structures for the development of immunosuppressive agents., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Mycobacterium tuberculosis is a pathogenic bacterium that is parasitic in macrophages and show high adaptation to the host's immune response. It can also trigger a complex immune response in the host. This relies on proteins encoded by a series of M. tuberculosis-encoded virulence genes. We found that the M. tuberculosis Rv3435c gene is highly conserved among pathogenic mycobacteria, and might be a virulence gene. To explore the gene function of Rv3435c, we used Mycobacterium smegmatis to construct a recombinant mycobacterium expressing Rv3435c heterologously. The results that Rv3435c is a cell wall-related protein that changes bacterial and colony morphology, inhibits the growth rate of recombinant mycobacteria, and enhances their resistance to various stresses. We also found that the fatty acid levels of the recombinant strain changed. Simultaneously, Rv3435c can inhibit the expression and secretion of inflammatory factors and host cell apoptosis, and enhance the survival of recombinant bacteria in macrophages. Experimental data indicated that Rv3435c might play an important role in Mycobacterium tuberculosis infection., Competing Interests: Declaration of Competing Interest The author declares that they have no conflict of interest., (Copyright © 2023. Published by Elsevier B.V.)

Ormosia hosiei Hemsl. et Wils (Fabaceae family) is an arbor species endemic to China. The seeds of O. hosiei have been used as traditional Chinese medicine to treat hernia, abdominal pain, blood stasis and amenorrhea. Cytisine-like and angustifoline type alkaloids were main components identified from this plant. In our research on the bioactive alkaloids from the promising Chinese medicinal plants, four new angustifoline type alkaloids (1-4) and a new cytisine-like alkaloid (5), named hosimosine A-E, together with 13 known analogues (6-18) were isolated from the seeds of O. hosiei. Their structures were elucidated by the extensive spectroscopic methods, especially the interpretation of NMR spectra and specific rotations, along with the methods of NMR and ECD calculation. Compounds 1-4 were identified as two pairs of epimers, whose relative configurations were deduced from density functional theory (DFT) calculations of NMR chemical shifts and DP4+ analysis, and absolute configurations were determined by comparison of their experimental and theoretical ECD spectra. Compound 5 displayed two sets of NMR data caused by the existence of tautomeric forms. Compounds 14, 17 and 18 were determined to be enantiomers of literature compounds. Some of the isolates exhibited moderate cytotoxic effects against HepG2, A2780 and MCF-7 cells., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Two unprecedented ent-18,19-dinoricetexane diterpenoid glycosides, named abieshanesides A (1) and B (2), together with seven known compounds, have been isolated from the dead trunks and branches of Abies beshanzuensis M.H. Wu. To our knowledge, abieshanesides A and B represent the first ent-18,19-dinoricetexane diterpenoid glycosides found in natural sources. Their structures and absolute configurations were elucidated by using a combination of spectroscopic techniques and comparison of experimental and calculated electronic circular dichroism (ECD) data. The MTT experiments showed that (E)-resveratrol (7) could inhibit viability of MH7A cells with the IC 50 value of 12.5 μM. Compound 7 was able to block MH7A cell proliferation and was associated with G 0 /G 1 -phase cell cycle arrest. Flow cytometric analysis showed that the treatment by 7 significantly induced the proliferation of MH7A cells in a dose-dependent manner., (Copyright © 2021 Elsevier B.V. All rights reserved.)

An investigation on the extract from the plant Trichilia sinensis Bentv. led to the isolation of 13 new limonoids (1-13), in which two were of khayalactone skeleton and 11 were phragmalin-type limonoids, and eight known phragmalin-type limonoids (14-21). Their structures were elucidated by using spectroscopic techniques and HRESIMS experiment. Compounds 6 and 17 displayed potent protein tyrosine phosphatase 1B inhibitory activity with IC 50 values of 1.2 ± 0.1 and 8.1 ± 0.5 μM, respectively., (Copyright © 2021 Elsevier B.V. All rights reserved.)