Structurally diverse deformed phenanthrenes from Strophioblachia fimbricalyx with cytotoxic activities by inducing cell apoptosis.

A group of phenanthrene derivatives with different deformed types, including four previously undescribed derivatives (1-4), an undescribed natural product (5) and five known compounds (6-10), were isolated from the leaves and stems of Strophioblachia fimbricalyx by molecular networking based on UPLC-MS/MS method. Their structures were established by 1D/2D NMR spectroscopy, HRESIMS, quantum chemistry calculation, and single crystal X-ray diffraction. In biogenic pathways, series of deformed phenanthrenes were all suspected to be derived from 6/6/6 tricyclic phenanthrenes with a gem-dimethyl unit in one ring as characteristic components of Strophioblachia. Fimbricalyxone (1) and trigoxyphin M (6) with a 6/6/5 tricyclic carbon skeleton were reported for the first time from the genus and fimbricalyxanhydride C (2) is the first example of anhydride type bearing a rare 8,9-oxycycle. All the isolates were evaluated for their cytotoxic activity against three tumor cell lines, and compounds 8 and 10 exhibited significant activity with IC50 values of 4.65-9.02 µM, and the structure-activity relationship of the deformed phenanthrenes was discussed. In addition, the X-ray structure of 8 and 10 and the antineoplastic activity of 10 are reported herein for the first time. Trigohowilol G (10) inhibiting the proliferation of A549 cells might be related to cell cycle distribution and the induction of S phase arrest, and it induced cell apoptosis through Bad/Bax/Cleaved PARP1 pathway.

Strophiofimbrins A and B: Two Rearranged Norditerpenoids with Novel Tricyclic Carbon Skeletons from Strophioblachia fimbricalyx.

Two rearranged norditerpenoids with novel tricyclic carbon skeletons, strophiofimbrin A (1) and strophiofimbrin B (2), were isolated from Strophioblachia fimbricalyx. Their structures were established by 1D/2D NMR spectroscopy, HRESIMS, quantum chemistry calculations, and X-ray diffraction analyses. 1 and 2 represented the first examples of diterpenoids with unprecedented 5/6/7-fused ring systems. In the proposed biosynthetic pathway, they were suspected to derive from cleistanthane norditerpenoids via ring opening, expansion, cyclization, and rearrangement based on the existence of phenanthrenone and cleistanthane diterpenoids from Strophioblachia and Trigonostemon, two closely related genera of the Euphorbiaceae family. Furthermore, compounds 1 and 2 exhibited significant proliferation inhibition and obvious neuroprotective effects.

A Comprehensive Risk Analysis of Transportation Networks Affected by Rainfall-Induced Multihazards.

Climate change and its projected natural hazards have an adverse impact on the functionality and operation of transportation infrastructure systems. This study presents a comprehensive framework to analyze the risk to transportation infrastructure networks that are affected by natural hazards. The proposed risk analysis method considers both the failure probability of infrastructure components and the expected infrastructure network efficiency and capacity loss due to component failure. This comprehensive approach facilitates the identification of high-risk network links in terms of not only their susceptibility to natural hazards but also their overall impact on the network. The Chinese national rail system and its exposure to rainfall-related multihazards are used as a case study. The importance of various links is comprehensively assessed from the perspectives of topological, efficiency, and capacity criticality. Risk maps of the national railway system are generated, which can guide decisive action regarding investments in preventative and adaptive measures to reduce risk.