Application of DMF–methyl sulfate adduct in the regioselective synthesis of 3-acylated indolizines

Beyond a solvent: triple roles of dimethylformamide in organic chemistry

N,N-Dimethylformamide (DMF) is frequently used as an aprotic solvent in chemical transformations in laboratories of academia as well as in those of chemical industry. In the present review, we will reveal that DMF is actually something much more than a solvent. It is a unique chemical since, as well as being an effective polar aprotic solvent, it can play three other important roles in organic chemistry. It can be used as a reagent, a catalyst, and a stabilizer.

Potential inhibitory effect of indolizine derivatives on the two enzymes: nicotinamide phosphoribosyltransferase and beta lactamase, a molecular dynamics study

Nicotinamide phosphoribosyl-transferases (NAMPT) are enzymes that play a role in targeting cancer metabolism, while beta lactamases are involved in bacterial resistance to beta-lactam antibiotics. Many protein inhibitors exhibit such property which is often correlated with their cellular potency. In order to understand such a phenomenon, the present article conducts an analysis of the dynamic behavior of complexes formed by the inhibitors, that is indolizine derivatives, with the studied enzymes. Both docking and molecular dynamics led to identification of their interactions and showed the mechanism of inhibition of the two studied enzymes. The differences in the behavior of ligand at the active sites of beta lactamases and nicotinamide phosphoribosyl-transferases are indicated by structural and enthalpy values.

Novel synthetic chalcones induce apoptosis in the A549 non-small cell lung cancer cells harboring a KRAS mutation

A series of novel chalcones were synthesized by the Claisen-Schmidt condensation reaction of tetralones and 5-/6-indolecarboxaldehydes. Treatment of human lung cancer cell line harboring KRAS mutation (A549) with the chalcones induced dose-dependent apoptosis. Cell cycle analyses and Western blotting suggested the critical role of the chalcones in interrupting G2/M transition of cell cycle. SAR study demonstrated that substituent on the indole N atom significantly affects the anticancer activity of the chalcones, with methyl and ethyl providing the more active compounds (EC₅₀: 110-200nM), Compound 1g was found to be >4-fold more active in the A549 cells (EC₅₀: 110nM) than in prostate (PC3) or pancreatic cancer (CLR2119, PAN02) cells. Furthermore, compound 1l selectively induced apoptosis of lung cancer cells A549 (EC₅₀: 0.55μM) but did not show measurable toxicity in the normal lung bronchial epithelial cells (hBEC) at doses as high as 10μM, indicating specificity towards cancer cells.

Pathways of ion-molecular interactions of nucleogenic phenyl cations with the nucleophilic centers of picolines

Background

The nuclear-chemical method brought unique opportunity for synthesis of unknown and hardly available organic compounds. Presence of tritium labeling allows one-step preparation of radioactive markers for the investigation of chemical and biological processes.

Methods

The ion–molecular reactions of nucleogenic phenyl cations with 4-picoline have been carried out. The phenyl cations were generated by spontaneous tritium β-decay within the tritium-labeled benzene. Both additions to the nitrogen and substitutions about the aromatic ring were able to be studied simultaneously.

Results

Unusual substitutions on both the α- and β-positions of the ring system have been revealed.

Conclusion

By unknown direct phenylation of nitrogen atom tritium-labeled N-phenylpicolinium derivatives, perspective biological markers have been synthesized.

Synthesis and SAR of Benzisothiazole- and Indolizine-β-d-glucopyranoside Inhibitors of SGLT2

A series of benzisothiazole- and indolizine-β-d-glucopyranoside inhibitors of human SGLT2 are described. The synthesis of the C-linked heterocyclic glucosides took advantage of a palladium-catalyzed cross-coupling reaction between a glucal boronate and the corresponding bromo heterocycle. The compounds have been evaluated for their human SGLT2 inhibition potential using cell-based functional transporter assays, and their structure-activity relationships have been described. Benzisothiazole-C-glucoside 16d was found to be an inhibitor of SGLT2 with an IC50 of 10 nM.

Regioselective synthesis of 3-acylindolizines and benzo- analogues via 1,3-dipolar cycloadditions of N-ylides with maleic anhydride

3-Acylindolizines (5a-5f) and their benzo- analogues 1-acylpyrrolo[1,2-a]quinolines (6a-6f) and 1-acylpyrrolo[2,1-a]isoquinolines (7a-7i) are regioselectively synthesized by a convenient one pot reaction of the corresponding pyridinium (quinolinium, isoquinolinium) ylide with maleic anhydride (MA) in the presence of the mild oxidant tetrakispyridinecobalt(ii) dichromate (TPCD). These reactions proceed via a tandem reaction sequence of 1,3-dipolar cycloaddition of azomethine ylide with MA, anhydride hydrolysis and oxidative bisdecarboxylation of the primary cycloadducts followed by dehydrogenative aromatization of the dihydroindolizines. TPCD serves as both decarboxylation and dehydrogenation reagent in the reactions. These results show that TPCD is a promising new reagent for bisdecarboxylation of aliphatic carboxylates.