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1 is the first nitrogen-oxidized homoerythrina-type alkaloid isolated from Cephalotaxus genus. 31 exhibited a significant antitumor effect in THP-1 and K562 cancer cell lines with GI50 values of 0.24 and 0.29 μM.

Eight cephalotaxine-type alkaloids (1–8), including two new compounds cephafortunines A and B (1–2), were isolated from the branches and leaves of Cephalotaxus fortunei var. alpina. Their structures were identified by a series of spectroscopic methods (MS, UV, IR, 1D, and 2D NMR) and comparison with the reported data of known analogs. The absolute configurations of 1 and 2 were determined by electronic circular dichroism (ECD) calculations. 1–8 were evaluated for their in vitro antiproliferation effects against two human leukemia cell lines (U937 and HL-60). All compounds showed different levels of antiproliferation effects against U937 cells with GI50 values of 4.21–23.70 μM. 4 and 5 were the most active against U937 cells with GI50 values of 4.21 and 6.58 μM and against HL-60 cells with GI50 values of 6.66 and 6.70 μM, respectively. 4 and 5 arrested HL-60 cell cycle in G0/G1 phase.

Cephafortunoids A–D (1–4), four new compounds, together with ten known ones (5–14), were isolated from the branches and leaves of Cephalotaxus fortunei var. alpina. 1 and 2 represent the first examples of Cephalotaxus troponoid diterpenoids featured an intact C20 skeleton with CH3-17 migrating to C-15 and C-13 respectively. 3 and 4 are novel cephalotane-type diterpenoids with an epoxy ring between C-12 and C-13. The structures of isolated compounds were established by extensive spectroscopic methods, electronic circular dichroism (ECD) calculations, and comparison with reported data. In in vitro bioassays, all isolated compounds were evaluated for their cytotoxic activities against human promyelocytic leukemia cells (HL-60), human acute monocytic leukemia cells (THP-1), human breast cancer cells (MDA-MB-231), and human prostate cancer cells (PC-3). 5–9 exhibited prominent cytotoxicity against HL-60 and THP-1 with GI50 values of 0.27–5.48 and 0.48–7.54 μM, respectively. 5–8 showed evident cytotoxicity against MDA-MB-231 and PC-3 with IC50 values of 1.96–10.66 and 2.72–13.99 μM, severally. 6 with an IC50 value of 2.72 ± 0.35 μM displayed stronger cytotoxicity against PC-3 than the positive control etoposide. The structure-activity relationship of these compounds and plausible biogenetic pathways for 1–4 were discussed.

In this paper, an evolution traffic network model considering the influence of the next-nearest neighbor is constructed. Using the model, we focus on studying the topology of the evolution traffic network in order to understand the traffic dynamics better. First, the influence of the next-nearest neighbor on the cumulative degree distribution is investigated by altering the values of the sensitivity coefficients; then the influence of some important parameters (density, the maximum velocity, etc.) is also discussed; subsequently, we study the trend of the degree of the hub when the values of the parameters change; some hubs of the evolution network are given at last. In this model, the hub is denoted as the node whose ranking of the degree is at the top a fixed percentage. By studying the statistical properties of the traffic network, we can grasp the traffic dynamics so as to take the appropriate methods for the better traffic situations.