The N 6-methyladenosine (m6A) demethylase FTO is overexpressed in acute myeloid leukemia (AML) cells and promotes leukemogenesis. We previously developed tricyclic benzoic acid FB23 as a highly potent FTO inhibitor in vitro. However, it showed a moderate antiproliferative effect on AML cells. In this work, we performed a structure–activity relationship study of tricyclic benzoic acids as FTO inhibitors. The analog 13a exhibited excellent inhibitory effects on FTO similar to that of FB23 in vitro. In contrast to FB23, 13a exerted a strong antiproliferative effect on AML cells. Like FTO knock down, 13a upregulated ASB2 and RARA expression and increased the protein abundance while it downregulated MYC expression and decreased MYC protein abundance. These genes are key FTO targets in AML cells. Finally, 13a treatment improved the survival rate of MONOMAC6-transplanted NSG mice. Collectively, our data suggest that targeting FTO with tricyclic benzoic acid inhibitors may be a potential strategy for treating AML.

In epigenetic research, the abnormality of protein methylation modification is closely related to the occurrence and development of tumors, which stimulates the interest of researchers in protein methyltransferase research and the efforts to develop corresponding specific small molecule inhibitors. Currently, the protein lysine methyltransferase SMYD2 has been identified as a promising new small molecule target for cancer therapy. But its biological functions have not been fully studied and relatively few inhibitors have been reported, thus this field needs to be further explored. This perspective provides a comprehensive and systematic review of the available resources in this field, including its research status, biological structure, related substrates and methylation mechanisms, and research status of inhibitors. In addition, this perspective elaborates in detail the current challenges in this field, our insights into what needs to be done next, rational drug design of novel SMYD2 inhibitors, and foreseeable development directions in the future.

Purine, one of nucleotide, is an important substance for metabolism regulation of the body. Purine plays a key role not only in the composition of coenzymes but also in the supply of energy. Since purine was artificially synthesized, it has always been an important scaffold for respiratory diseases, cardiovascular diseases, and anti-tumor and anti-viral drugs. In addition to being widely used as competitive antagonists in the treatment of diseases, purines can be used in combination with other drugs and as precursors to benefit human life. Unfortunately, few new discoveries have been made in recent years. In this article, purine drugs on the market have been classified according to their different targets. In addition, their mechanism of action and structure-activity relationship have been also introduced. This paper provides details of the signaling pathways from when the purine drugs bind to the respective receptors on the surface of cells and the consequent reactions within the cell which finally affect the targeted diseases. The various receptors and biological reactions involved in the signaling for respective disease targets within the cells are discussed in detail.

Many drugs have adverse absorption, distribution, metabolism, and excretory (ADME) properties that prevent their widespread use or limit their use in some indications. In addition to preparation techniques and prodrug strategies, deuterium modification is a viable method for improving ADME properties. Deuterated drugs have attracted increasing attention from the pharmaceutical industry in recent years. To date, two deuterated drugs have been approved by the FDA. In 2017, austedo was approved by the FDA as a new drug for Huntington's disease in the United States, the first deuterium drug to be marketed worldwide. Recently (June 9, 2021), donafinil has been listed in China; this result has caused major pharmaceutical companies and the pharmaceutical industry to pay attention to deuterium technology again. In addition, BMS-986165, RT001, ALK-001, HC-1119, AVP-786 and other drugs are in phase Ⅲ clinical studies, and some solid deuterium compounds have entered phase I and Ⅱclinical trials. The deuterium strategy has been widely used in pharmaceutical research and has become a hot spot in pharmaceutical research in recent years. In this paper, the research and development of deuterated drugs are reviewed, and the influence of deuterium modification on drugs, the advantages of deuterium strategies and the synthesis strategies of deuterated drugs are mainly introduced. Hoping to provide references for clinical application, the discovery of new deuterium chemical entities and research and development of new deuterated drugs.

In the paper by Shi, Hu & Rao [http://scripts.iucr.org/cgi-bin/paper?ww6211], the title is given incorrectly. The chemical name should appear as `3,6‐Diethyl‐N,N′‐bis(3‐methyl­phenyl)‐1,4‐di­hydro‐1,2,4,5‐tetrazine‐1,4‐di­carbox­amide'.