2284-20-0Relevant articles and documents
Microwave mediated synthesis of 2-aminooxazoles
Cronin, Adam,Eagon, Scott,Gleason, Cameron,Johnson, Hunter,Kimball, Joshua J.,Klug, Trevan,Lazaro, Horacio,Liyanage, Duminda,Manjunath, Aashrita,O'Brien, Eli,Schioldager, Ryan,Schmid, Connor,Soderberg, Nathan
supporting information, (2021/12/14)
A microwave mediated synthesis of 2-aminooxazoles at 150 °C was developed, providing products with a variety of functional groups. The reaction takes 5 min and provides product with a simple precipitation at moderate to good yields without the need for recrystallization or flash chromatography.
Synthesis of isothiocyanates using DMT/NMM/TsO? as a new desulfurization reagent
Janczewski, ?ukasz,Kolesińska, Beata,Kr?giel, Dorota
, (2021/05/29)
Thirty-three alkyl and aryl isothiocyanates, as well as isothiocyanate derivatives from esters of coded amino acids and from esters of unnatural amino acids (6-aminocaproic, 4-(aminomethyl)benzoic, and tranexamic acids), were synthesized with satisfactory or very good yields (25–97%). Synthesis was performed in a “one-pot”, two-step procedure, in the presence of organic base (Et3 N, DBU or NMM), and carbon disulfide via dithiocarbamates, with 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium toluene-4-sulfonate (DMT/NMM/TsO? ) as a desulfurization reagent. For the synthesis of aliphatic and aromatic isothiocyanates, reactions were carried out in a microwave reactor, and selected alkyl isothiocyanates were also synthesized in aqueous medium with high yields (72–96%). Isothiocyanate derivatives of L-and D-amino acid methyl esters were synthesized, under conditions without microwave radiation assistance, with low racemization (er 99 > 1), and their absolute configuration was confirmed by circular dichroism. Isothiocyanate derivatives of natural and unnatural amino acids were evaluated for antibacterial activity on E. coli and S. aureus bacterial strains, where the most active was ITC 9e.
4-Dimethylaminopyridine-catalyzed synthesis of isothiocyanates from amines and carbon disulfide
Rong, Hao-Jie,Chen, Tao,Xu, Ze-Gang,Su, Tian-Duo,Shang, Yu,Wang, Yong-Qiang,Yang, Cui-Feng
, (2021/03/03)
Isothiocyanates were synthesized by reactions between primary amines and CS2 in the presence of 4-dimethylaminopyridine as a catalyst and tert-butyl hydroperoxide as an oxidant. Various aryl, benzyl, alkyl, and hydroxyl amines were transformed into the corresponding isothiocyanates in 41–82% yields.
NaOH-promoted one-pot aryl isothiocyanate synthesis under mild benchtop conditions
Li, Hang,Liu, Xinyun,Yin, Xiaogang
supporting information, p. 839 - 844 (2021/05/27)
In this work, we have established a green synthesis of aryl isothiocyanates promoted by the low-cost and readily available NaOH from aryl amines and carbon disulfide in a one-pot procedure. The developed protocol features no extra desulfurating reagents and mild benchtop conditions, in which NaOH serves as both the base and the desulfurating reagent to decompose the dithiocarbamate intermediate. Fourteen examples of aryl amines bearing electronic neutral, rich and poor substituents, as well as benzylamine, have proved to be compatible substrates in the developed method to furnish the corresponding isothiocyanates. The reaction has been performed on a gram scale to further demonstrate its synthetic utility. Compared to the reported base-promoted synthesis of aryl isothiocyanates that requires the use of special equipment, such as the ball mill or the microwave reactor, the simplicity in operation and scalability enables this method to efficiently access a variety of aryl isothiocyanates.
Diaryl-substituted thiosemicarbazone: A potent scaffold for the development of New Delhi metallo-β-lactamase-1 inhibitors
Li, Jia-Qi,Sun, Le-Yun,Jiang, Zhihui,Chen, Cheng,Gao, Han,Chigan, Jia-Zhu,Ding, Huan-Huan,Yang, Ke-Wu
, (2020/12/30)
The superbug infection caused by New Delhi metallo-β-lactamase (NDM-1) has become an emerging public health threat. Inhibition of NDM-1 has proven challenging due to its shuttling between pathogenic bacteria. A potent scaffold, diaryl-substituted thiosemicarbazone, was constructed and assayed with metallo-β-lactamases (MβLs). The obtained twenty-six molecules specifically inhibited NDM-1 with IC50 0.038–34.7 μM range (except 1e, 2e, and 3d), and 1c is the most potent inhibitor (IC50 = 0.038 μM). The structure-activity relationship of synthetic thiosemicarbazones revealed that the diaryl-substitutes, specifically 2-pyridine and 2-hydroxylbenzene improved inhibitory activities of the inhibitors. The thiosemicarbazones exhibited synergistic antimycobacterial actions against E. coli-NDM-1, resulted a 2–512-fold reduction in MIC of meropenem, while 1c restored 16–256-, 16-, and 2-fold activity of the antibiotic on clinical isolates ECs, K. pneumonia and P. aeruginosa harboring NDM-1, respectively. Also, mice experiments showed that 1c had a synergistic antibacterial ability with meropenem, reduced the bacterial load clinical isolate EC08 in the spleen and liver. This work provided a highly promising scaffold for the development of NDM-1 inhibitors.
A more sustainable isothiocyanate synthesis by amine catalyzed sulfurization of isocyanides with elemental sulfur
Nickisch,Conen,Gabrielsen,Meier
, p. 3134 - 3142 (2021/01/28)
Isothiocyanates (ITCs) are typically prepared using amines and highly toxic reagents such as thiophosgene, its derivatives, or CS2. In this work, an investigation of a multicomponent reaction (MCR) using isocyanides, elemental sulfur and amines revealed that isocyanides can be converted to isothiocyanates using sulfur and catalytic amounts of amine bases, especially DBU (down to 2 mol%). This new catalytic reaction was optimized in terms of sustainability, especially considering benign solvents such as Cyrene or γ-butyrolactone (GBL) under moderate heating (40 °C). Purification by column chromatography was further optimized to generate less waste by maintaining high purity of the product. Thus, E-factors as low as 0.989 were achieved and the versatility of this straightforward procedure was shown by converting 20 different isocyanides under catalytic conditions, while obtaining moderate to high yields (34-95%). This journal is
Discovery of quinazoline derivatives as a novel class of potent and in vivo efficacious LSD1 inhibitors by drug repurposing
Li, Zhonghua,Li, Zhongrui,Ma, Jinlian,Miao, Jinxin,Qin, Tingting,Yang, Nian,Zhang, Xinhui,Zhang, Zhenqiang,Zhao, Taoqian,Zhao, Xuan
, (2021/08/19)
Histone lysine-specific demethylase 1 (LSD1) is an important epigenetic modulator, and is implicated in malignant transformation and tumor pathogenesis in different ways. Therefore, the inhibition of LSD1 provides an attractive therapeutic target for cancer therapy. Based on drug repurposing strategy, we screened our in-house chemical library toward LSD1, and found that the EGFR inhibitor erlotinib, an FDA-approved drug for lung cancer, possessed low potency against LSD1 (IC50 = 35.80 μM). Herein, we report our further medicinal chemistry effort to obtain a highly water-soluble erlotinib analog 5k (>100 mg/mL) with significantly enhanced inhibitory activity against LSD1 (IC50 = 0.69 μM) as well as higher specificity. In MGC-803 cells, 5k suppressed the demethylation of LSD1, indicating its cellular activity against the enzyme. In addition, 5k had a remarkable capacity to inhibit colony formation, suppress migration and induce apoptosis of MGC803 cells. Furthermore, in MGC-803 xenograft mouse model, 5k treatment resulted in significant reduction in tumor size by 81.6% and 96.1% at dosages of 40 and 80 mg/kg/d, respectively. Our findings indicate that erlotinib-based analogs provide a novel structural set of LSD1 inhibitors with potential for further investigation, and may serve as novel candidates for the treatment of LSD1-overexpressing cancers.
Method for preparing isothiocyanate by alkali catalysis
-
Paragraph 0046-0051, (2020/11/22)
The invention discloses a method for preparing isothiocyanate by alkali catalysis, which realizes one-step conversion from primary amine to isothiocyanate under the alkali catalysis. The method comprises the following steps: dissolving primary amine in methanol at -20 to 40 DEG C to obtain a primary amine solution, sequentially adding an alkali catalyst, carbon disulfide and an oxidant into the primary amine solution, carrying out stirring reaction, and carrying out reduced pressure distillation; finally, carrying out extraction and column chromatography purification to obtain the product; wherein the molar ratio of the primary amine to the base catalyst to the carbon disulfide to the oxidizing agent is 1: (0.05-0.2) : (2.5-10) : (1.2-4.5), the structural general formula of the primary amine is RNH2, the structural general formula of the isothiocyanate is R-N=C=S, and the R group is alkyl, aryl, benzyl or allyl. Herein, primary amine reacts with carbon disulfide under the action of analkali catalyst and an oxidizing agent to directly generate isothiocyanate, so that sulfur phosgene and excessive alkali are avoided, and the whole reaction atom economy is high, operation is simple.The method is more suitable for preparation of functional organic intermediates and active biomolecules.
Thiosemicarbazone-based lead optimization to discover high-efficiency and low-toxicity anti-gastric cancer agents
Bo-Wang,He, Zhang-Xu,Li, Yi-Han,Liu, Hong-Min,Ma, Li-Ying,Ma, Qin,Tao, Yuan-Yuan,Wang, Hao-Jie,Wu, Hui-Pan,Zhang, Xin-Hui,Zhao, Bing
, (2020/05/19)
In this paper, a series of thiosemicarbazone derivatives containing different aromatic heterocyclic groups were synthesized and the tridentate donor system of the lead compound was optimized. Most of the target compounds showed improved antiproliferative activity against MGC803 cells. SAR studies revealed that compound 5d displayed significant advantages in inhibition effect with an IC50 value of 0.031 μM, and better selectivity between cancer and normal cells than 3-AP and DpC (about 15- and 5-fold improved respectively). Besides, compound 5d showed selective antiproliferative activity in not only other cancer cells but also different gastric cancer cell lines. In-depth mechanism studies showed that compound 5d could induce mitochondria-related apoptosis which might be related to the elevation of intracellular ROS level, and cause cell cycle arrest at S phase. Moreover, 5d could evidently suppress the cell migration and invasion by blocking the EMT (epithelial–mesenchymal transition) process. Consequently, our studies provided a lead optimization strategy of thiosemicarbazone derivatives which would contribute to discover high-efficiency and low-toxicity agents for the treatment of gastric cancer.
