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Tigliane and rhamnofolane diterpenoids bearing glycosyl substituents are rarely found in nature. In the current study, seven new tigliane glycosides, euphorwallsides A - G (1-7), and five new rhamnofolane glycosides, euphorwallsides H - L (8-12), were isolated from the whole plants of Euphorbia wallichii. Their structures were elucidated by a combination of spectroscopic, computational, and chemical means. The aglycones of 1-5 represent a rare class of 13-deoxygenated tiglianes, while those of 8-12 represent the first examples of 4-deoxygenated rhamnofolanes. 2, 3, 5, 7, 8, and 12 showed significant neuroprotective effects on sodium nitroprusside (SNP)-induced neuronal death in pheochromocytoma cell line PC-12 at 10 μM, being more active than the clinical drug, edaravone. Mechanistic study revealed that the most active compound, 3, could inhibit reactive oxygen species (ROS) accumulation and restore the mitochondrial membrane potential via modulating the Nrf2 signaling pathway in PC-12 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 © 2022 Elsevier Inc. All rights reserved.)

Five tigliane ( 1 - 5 ) and one ingenane ( 6 ) diterpenoids were isolated from the ethanol extract of Euphorbia tirucalli . The structures of these compounds were identified based on analysis of their spectroscopic data. Among them, compound 12- O -(2 E ,4 E ,6 E ,8 E -tetradecatetraenoyl)-13- O -isobutyroyl-4 β -deoxyphorbol ( 1 ) was a new tigliane. The Rho123 effluxion assay showed that tiglianes with a trans -fused 5/7 ring system such as compounds 1 , 2 , and 4 had potent inhibitory activity against P-glycoprotein in HepG2/ADR cells.

Three new diterpenoids, euphopanes A-C ( 1 - 3 ), including one ent -isopimarane ( 1 ), one ent -abietane ( 2 ) and one cembrane ( 3 ), along with five known compounds ( 4 - 8 ) were isolated from the roots of Euphorbia pekinensis . Their structures were elucidated by extensive spectroscopic analysis, and the absolute configurations of compounds 1 - 3 were determined by ECD calculations. All the isolates were screened for the cytotoxicity against three cancer cell lines (C4-2B, C42B/ENZR, and MDA-MB-231), and compounds 1 , 2 , and 4 showed significant cytotoxicity against human prostate cancer cells C4-2B with IC 50 values of 14.3, 16.9, and 15.3 μM, respectively.

Seven previously undescribed polycyclic diterpenoids, euphonoids A-G, including four ent-abietanes, two ent-atisanes, and one ent-kaurene, along with 26 known analogues were isolated from the roots of Euphorbia fischeriana. The structures of the undescribed compounds were elucidated by spectroscopic analysis, ECD calculations, and single crystal X-ray diffraction. Besides, the structure of a previously reported ent-abietane diterpenoid, fischeriabietane A, was revised. All the isolates were screened for the cytotoxicities against five cancer cell lines. Euphonoid A, fischeriabietane A, 11-oxo-ebracteolatanolide B, caudicifolin, jolkinolide B, and methyl-8,11-3-dihydroxy-12-oxo-ent-abietadi-13,15(17)-ene-16-oate showed significant inhibitory activities against human prostate cancer C4-2B and C4-2B/ENZR cell lines, with IC 50 values being less than 10 μM. The brief structure-activity relationships (SARs) of these diterpenoids were also discussed., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Bioassay-guided fractionation of the ethanolic extract of the roots of Euphorbia kansui led to the isolation of two new ingenane diterpenoids, euphorkans A (1: ) and B (2: ), together with 16 known analogues (3:  - 18: ). Their structures were determined by combined spectral and chemical methods. All the isolates were evaluated for their inhibitory effects on lipopolysaccharide-induced nitric oxide production in RAW264.7 macrophage cells. Compounds 1:  - 6: and 10:  - 13: exhibited pronounced inhibitory activity with IC 50 values in the range of 2.78 - 10.6 µM, and were more potent than the positive control, quercetin (IC 50  = 15.8 µM). Compounds 1: and 5: were selected for further assays toward the key inflammation mediators TNF- α and IL-6, and showed a significant inhibition in a dose-dependent manner. The preliminary mechanistic study revealed that 1: and 5: inhibited NF- κ B activity, which may exert a role in their anti-inflammatory activity., Competing Interests: The authors declare no conflict of interest., (Georg Thieme Verlag KG Stuttgart · New York.)