Linear triquinane sesquiterpenoids represent an important class of natural products. Most of these compounds were isolated from fungi, sponges, and soft corals, and many of them displayed a wide range of biological activities. On account of their structural diversity and complexity, linear triquinane sesquiterpenoids present new challenges for chemical structure identification and total synthesis. 118 linear triquinane sesquiterpenoids were classified into 8 types, named types I–VIII, based on the carbon skeleton and the position of carbon substituents. Their isolation, structure elucidations, biological activities, and chemical synthesis were reviewed. This paper cited 102 articles from 1947 to 2018.

The composition of the culture medium has great influence on the metabolite production of the marine fungus Pseudallescheria boydii F44-1. By adding amino acids to GPY culture medium, two new bisindole alkaloids, pseudboindoles A and B (1 and 2), together with 11 known indole alkaloids were isolated from the culture broth. Their structures were elucidated by comprehensive analysis of the NMR, MS, IR, and UV spectra. The 3,3′-cyclohexylidenebis(1H-indole) (3) showed cytotoxic activity against various cancer cell lines.

Three new compounds, monarubins A–C (1, 6 and 13), together with ten known compounds, including four alkaloids (2–5), two isocoumarins (7 and 8) and four polyketides (9–12), were isolated from marine shellfish-associated fungus Monascus ruber BB5. The structures were determined on the basis of the 1D and 2D NMR, MS, UV and IR data. The absolute configurations of compounds 3, 6 and 13 were determined by ECD calculations. The NMR data of compounds deoxyhydroxyaspergillic acid (3) and 2-hydroxy-6-(1-hydroxy-1-methylpropyl)-3-sec-buthylpyrazine (4) were first reported. All of the isolated compounds were evaluated for their cytotoxic activities against human nasopharyngeal carcinoma cell lines CNE1, CNE2, SUNE1 and HONE1 and hepatocellular carcinoma cell lines QGY7701 and HepG2. Monarubin B (6) displayed potent cytotoxicities against the cancer cell lines HepG2 and QGY7701 with IC₅₀ values of 1.72 and 0.71 μΜ, respectively; lunatinin (7) showed moderate cytotoxic activities against the cancer cell lines HepG2, QGY7701 and SUNE1 with the IC₅₀ values of 9.60, 7.12 and 28.12 μΜ, respectively.