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Guided by an MS/MS-based molecular networking, six undescribed cassane diterpenoids and three known ones were isolated and identified from the seeds of Caesalpinia sappan. Their structures were unequivocally elucidated by extensive spectroscopic analyses and electronic circular dichroism (ECD) calculations. Cytotoxic evaluation showed that phanginin JA exhibited significant antiproliferative activities against human non-small cell lung cancer (A549) cells with IC 50 values of 16.79±0.83 μM. Further flow cytometry analysis revealed that phanginin JA could exert apoptotic effect of A549 cells by arresting cell cycle in G0/G1 phase., (© 2023 Wiley-VHCA AG, Zurich, Switzerland.)

Molecules with diterpene skeletons often possess valuable medicinal properties. Two new diterpenes 1α,6α,7β-triacetoxy-5α-hydroxy-14β-ethyl-O-vouacapane (1) and 2α-acetoxy-14,15-cyclopimara-7β,16-diol (2) were isolated from the seeds of Caesalpinia minax Hance. Their structures were established on the basis of extensive spectroscopic analyses, including HR-ESI-MS, UV, IR, 1D, and 2D NMR (HSQC, HMBC, NOESY) methods. The stereochemical structure of 1 was confirmed via the circular dichroism spectrum and calculated ECD experiment. The inhibitory activity of nitric oxide production of RAW264.7 macrophages stimulated by lipopolysaccharide of compounds 1 and 2 was evaluated, and compound 1 was found to show significant inhibitory effect.

Four compounds were isolated from Daphne giraldii callus cells, and their structures were characterized as daphnenone (1), daphnolon (2), R-( - )-1-(4'-hydroxyphenyl)-3-hydroxy-5-phenyl-1,5-pentandione (3), and S-(+)-daphneolone-4'-O-β-d-glucoside (4) on the basis of MS, NMR spectrographic analysis, and chemical methods. All of the four compounds possessed C6-C5-C6 carbon skeleton, and among them, 3 and 4 were two new compounds. In activity screening test, compounds 1, 2, 3, and 4 showed different degrees of cytotoxic activity against the tumor cells of human melanoma A375-S2 by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium hydrobromide method, with IC(50) values of 29.8, 51.0, 41.0, and 150.0 μM, respectively. Furthermore, we found the important target which could explain the cytotoxic mechanism of the four compounds by using autodock 4.0, a structure-guided discovery approach, and the important residues CYS532, GLY534, and SER535 of B-Raf kinase have been discovered.

Three new cassane-diterpene-lactones, methyl 1α,7β-diacetoxy-5α,12α-dihydroxy-cass-13(15)-en-16,12-olide-17β-carboxylate (1), methyl 7β-acetoxy-1α,5α,12α-trihydroxy-cass-13(15)-en-16,12-olide-17β-carboxylate (2), and 12α-ethoxyl-1α,6α,7β-triacetoxy-5α,14β-dihydroxy-cass-13(15)-en-16,12-olide (3), were isolated from the seeds of Caesalpinia minax Hance. Their structures were established on the basis of HR-ESI-MS, 1D and 2D NMR spectral analysis.

The Nakagami parameter associated with the Nakagami distribution estimated from ultrasonic backscattered signals reflects the scatterer concentration in a tissue. A nonfocused transducer does not allow tissue characterization based on the Nakagami parameter. This paper proposes a new method called the noise-assisted Nakagami parameter based on empirical mode decomposition of noisy backscattered echoes to allow quantification of the scatterer concentration based on data obtained using a nonfocused transducer. To explore the practical feasibility of the proposed method, the current study performed experiments on phantoms and measurements on rat livers in vitro with and without fibrosis induction. The results show that using a nonfocused transducer makes it possible to use the noise-assisted Nakagami parameter to classify phantoms with different scatterer concentrations and different stages of liver fibrosis in rats more accurately than when using techniques based on the echo intensity and the conventional Nakagami parameter. However, the conventional Nakagami parameter and the noise-assisted Nakagami parameter have different meanings: the former represents the statistics of signals backscattered from unresolvable scatterers, whereas the latter is associated with stronger resolvable scatterers or local inhomogeneity caused by scatterer aggregation.

The chemical constituent research on the ethyl acetate extracts of fermentation liquid of the marine fungus Trichoderma atroviride G20-12 led to the isolation of two new compounds, 2-hydroxybutan-3-yl 5'-(2''-hydroxy-N-(2'''-oxobutan-3'''-yl)propanamido)butanoate (1) and 3-hydroxy-5-(4-hydroxybenzyl)dihydrofuran-2(3H)-one (2). The structures of the new compounds were determined by spectroscopic and chemical analysis.

From the dried aerial part of Acanthopanax senticosus, a new coumarin glycoside, eleutheroside B(2) (1), and a new sesquiterpenoid, oplopanone B (2), were isolated. Their structures were elucidated on the basis of chemical and spectroscopic methods.

Objective: To study the chemical constituents of Caesalpinia minax., Method: The chemical constituent was isolated by various chromatographic metheds and its structure was elucidated by the analysis of spectral data and physiochemical properties., Result: One diterpenoid compound was isolated from the 95% ethanolic extract of C. minax, and identified as 12alpha -methoxyl-14beta-hydroxy-lalpha, 6alpha, 7beta-triacetoxycass-13 (15)-en-16, 12-olide., Conclusion: Neocaesalpin L1 was a new compound and named as neocaesalpin L1.