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This study concerns the synthesis of Anthraquinone analogue 2-chloro-5-(methylsulfonamide) anthraquinone and its effect on antioxidant property. Nitration of phthalic anhydride at 80 °C followed to yield a mixture of 2-nitrophthalic acid and 3-nitrophthalic acid. After following a sequence of reactions the product 2-Chloro 5-amino anthraquinone was formed. Then this compound was treated with methanesulfonyl chloride in presence of K2CO3 in the solvent acetone to produce 2-chloro-5-(methylsulfonamide) anthraquinone. The structure of the compound so obtained was exposed to structural characterization by following Infra Red (IR) and 1H Nuclear Magnetic Resonance spectroscopic (1H NMR) analyses. The antioxidant property of the compound was assessed by In vitro methods consisting of 2,2′-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azinobis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) procedures. It was suggested that the compound has the potent antioxidant property.

Search for new and efficient antibiotic is crucial because of microbial drug resistance and problems with side effects of the administered medication. In this study, we evaluate the in vitro microbiological activity of muramyl dipeptide derivatives, retro-tuftsin derivatives (i.e., tuftsin with reversed amino acid sequences), and combinations of retro-tuftsin derivatives with substituted anthraquinones. The potency of the investigated derivatives towards methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae ESBL (extended-spectrum β-lactamases) was compared based on the spectroscopically-measured minimal inhibitory concentrations (MIC values). The bacterial growth have also been studied with different concentrations of compounds. Statistical analysis of the results revealed that certain modifications lead to promising activity against S. aureus (anthraquinone analogue – 3c and retro-tuftsin derivative – 2b), while other derivatives exhibit activity against P. aeruginosa (muramyl dipeptide derivative – 1d and retro-tuftsin derivative – 2b). The obtained results of microbiological activity indicate that the structure of the tested compounds may be the basis for further modifications.

Three anthraquinone analogues (1–3) were isolated by phytochemical work on EtOAc-soluble ingredients extracted from the roots of Polygonatum odoratum. The structures of all isolates were elucidated by NMR, MS and CD experiments, of which 1 (polygodoquinone A) was identified as a new anthraquinone derivative. Specifically, 1 represents an unusual structure composed of a naphthoquinone derivative linked to an anthraquinone via a C-C bond. 1–3 exhibited remarkable influenza A virus inhibitory activity with IC50 values of 11.4, 11.0, and 2.3 μM, respectively, which were better than ribavirin as the positive control.

A continuous phytochemical study on the seeds of Senna obtusifolia (Syn.: Cassia obtusifolia) led to the isolation of a new anthraquinone analogue, obtusifolin-2-O-β-D-(6’-O-α,β-unsaturated butyryl)-glucopyranoside (1) and a new eurotinone analogue, epi-9-dehydroxyeurotinone-β-D-glucopyranoside (2). Their structures were established mainly by NMR and MS experiments as well as the necessary chemical evidences. Their inhibitory effects on two organic anion transporters (OAT1 and OAT3) were investigated and the results showed that 1 exhibited a strongly specific inhibitory effect on OAT1 at 100 μM.

A newly synthesized anthraquinone derivative 'N-(2-methylanthraquinone)-4-(2-aminoethyl) phenol' (Tyan) were characterized as a fluorophore from photophysical analysis by measuring the UV-Vis absorptive (λ(ex) = 325 nm) and fluorescence emitive (λ(em) = 660 nm) values. Density functional theory additionally supported the spectroscopic data by modulation of highest occupied molecular orbital rather than lowest unoccupied molecular orbital due to the affect of tyramine moiety present in Tyan. The pharmacological importance of Tyan was evaluated by molecular docking with human serum albumin. The molecular docking of the Tyan was performed with the crystal structure of human serum albumin (PDB entry 1E78), which shows binding in all the three domains of human serum albumin corresponding to -7.74 as the GScore. Moreover, the interactions of human serum albumin with Tyan were assessed employing fluorescence spectroscopy under simulative physiological conditions, and the binding constant for the interaction at 25 °C was found to be 0.6 × 10(3)/M.