Machine Learning Models for Predicting Bioavailability of Traditional and Emerging Aromatic Contaminants in Plant Roots.

To predict the behavior of aromatic contaminants (ACs) in complex soil-plant systems, this study developed machine learning (ML) models to estimate the root concentration factor (RCF) of both traditional (e.g., polycyclic aromatic hydrocarbons, polychlorinated biphenyls) and emerging ACs (e.

Cephalotane diterpenoids: structural diversity, biological activity, biosynthetic proposal, and chemical synthesis.

Covering: up to the end of 2023Cephalotane diterpenoids are a unique class of natural products exclusive to the genus , featuring a rigid 7,6,5,6-fused tetracyclic architecture. The study of cephalotanes dates back to the 1970s, when harringtonolide (1), a troponoid with a peculiar norditerpenoid carbon skeleton, was first discovered. In recent years, prototype C diterpenoids proposed as cephalotane were disclosed, which triggered intense studies on this diterpenoid family.

Spatial distribution and risk assessment of polycyclic aromatic hydrocarbons in soils from contaminated sites in Eastern China.

A total of 16 polycyclic aromatic hydrocarbons (PAHs) were measured in 28 soil column samples from two contaminated industrial sites in Eastern China. The total concentration of 16 PAHs (∑PAHs) in the surface soil (0-20 cm) was measured up to 52,600 ng/g (dry weight basis) with a remarkable spatial difference in the studied contaminated sites. The concentrations of the ∑PAHs in soils decreased with the increase in soil depth (0-10 m).

Highly Modified Sesquiterpene Lactones with Cytotoxic Activities from .

Three new germacranolide sesquiterpene lactones (SLs), strochunolides A-C (-, respectively), and a new guaianolide SL, strochunolide D (), were isolated from and structurally characterized. Compound is the first example of a dihomo-germacranolide SL, characterized by an unprecedented 6/10/5 tricyclic scaffold incorporating an additional fused δ-lactone C-ring. The structure of a known germacranolide SL, spicatolide C (), was revised as its 8-epimer.

Cephalotane-type C diterpenoids from var. .

Seventeen new cephalotane-type diterpenoids, fortalides A-Q (1-17), along with five known analogues, were isolated from the seeds of var. . Their structures were determined by extensive spectroscopic methods, as well as electronic circular dichroism (ECD) and X-ray crystallographic data analyses.

Cephalodiones A-D: Compound Characterization and Semisynthesis by [6+6] Cycloaddition.

Cephalodiones A-D (1-4), the first example of C -norditerpenoid dimers, were isolated and fully characterized from a Cephalotaxus plant. These new skeletal natural products shared a unique tricyclo[6.4.

17- nor-Cephalotane-Type Diterpenoids from Cephalotaxus fortunei.

Seventeen new 17- nor-cephalotane-type diterpenoids, fortalpinoids A-Q (1-17), were isolated from the seeds of Cephalotaxus fortunei var. alpine. Compound 12 represents the first 17- nor-cephalotane-type diterpenoid featuring an 8-oxabicyclo[3.

Maximumins A-D, Rearranged Labdane-Type Diterpenoids with Four Different Carbon Skeletons from Amomum maximum.

Four highly rearranged labdane-type diterpenoids, maximumins A-D (1-4) possessing different new carbon skeletons, together with a biosynthetically related known analog 5 were isolated from Amomum maximum. The structures of new compounds with absolute configurations were characterized by spectroscopic and computational approaches. The plausible biogenetic pathways for 1-4 were proposed.