Two new N-acetyldopamine tetrapolymers, cicadamide A (1) and cicadamide B (2), were isolated from periostracum Cicadae, and their structures were elucidated as 3-acetylamino-7-(3″-acetylamino-7″-(N-acetyl-2‴-aminoethyl)-1″,4″-benzodioxan-2″-yl)-2-(2'-(3″″,4″″-dihydroxyphenyl)-3'-acetylamino-1',4'-benzodioxan-7'-yl)-1,4-benzodioxane (1) and 3-acetylamino-7-(3″-acetylamino-6″-(N-acetyl-2‴-aminoethyl)-1″,4″-benzodioxan-2″-yl)-2-(2'-(3″″,4″″-dihydroxyphenyl)-3'-acetylamino-1',4'-benzodioxan-7'-yl)-1,4-benzodioxane (2), by the combined analysis of 1D NMR and 2D NMR, and mass spectrometry. Pharmacological investigation on two compounds obtained in this study showed that part of them had anti-inflammatory activities.

[reaction: see text] Two novel bisdolabrane backbone tetraditerpenoids, tagalsins I (1) and J (2), were isolated from the mangrove plant, Ceriops tagal, and their structures were elucidated by means of extensive two-dimensional NMR (COSY, HMQC, HMBC, and NOESY), IR, and MS data analysis. The stereochemistry of 1 was further determined by single-crystal X-ray diffraction.

A new (1, grincamycin L) and two known (2 and 3) angucycline derivatives were obtained from the fermentation of deepsea-derived Streptomyces lusitanus OUCT16-27 strain. The structures of 1−3 were elucidated based on the LC-MS analysis together with 1D and 2D NMR data assignment. In the antibacterial assay, 1 and 2 exhibited moderate growth inhibition against multi-drug resistant (MDR) strains of E. faecium, E. faecalis and S. aureus with the minimum inhibitory concentrations (MICs) of 3.12-6.25 µg/mL.