Stereoselective synthesis of 2-(2,4-dinitrophenyl)hydrazono- and (2-tosylhydrazono)-4-oxo-thiazolidine derivatives and screening of their anticancer activity

Brønsted acidic surfactant [HDMM]+ [HSO4]-: a green microreactor assembly for stereoselective synthesis of novel thiazolyl-pyrazole-chromen-2-ones in water

A novel Brønsted acidic surfactant was synthesized and employed as a catalyst for a one-pot multi-component reaction. Small angle X-ray scattering (SAXS) analysis was performed, which confirmed that the micelles exhibited an average diameter of 3.1 nm and average inter-micellar distance of 0.49 nm. Ground state density functional theory (DFT) calculation was performed on the surfactant molecule to optimize the geometrical structure. A series of novel thiazolyl-pyrazole-chromen-2-one derivatives were efficiently synthesized through a convenient one-pot multi-component reaction of substituted 3-acetoacetyl coumarins, thiosemicarbazide and dialkyl acetylene dicarboxylates in water using a novel hexadecyl methyl morpholinium hydrogen sulfate [HDMM]+ [HSO4]- as surfactant. Operational simplicity, stereoselective synthesis, quick access to the desired products, high purity and good to excellent yields are the key advantages of this approach. This work remarkably highlights the dual novelty as a new class of thiazolyl-pyrazole-chromen-2-one derivatives as well as a [HDMM]+ [HSO4]- surfactant.

Convenient synthesis and X-ray determination of 2-amino-6H-1,3,4-thiadiazin-3-ium bromides endowed with antiproliferative activity

A new series of 1,3,4-thiadiazin-3-ium bromide derivatives 9a-g were prepared as a six-member ring by interactions between 4-substituted thiosemicarbazides 8a-e and α-halo ketones 2a,b. The reaction was conducted using hydrazine-NH2 and yielded a hexagonal shape. The structures of all obtained compounds have been verified using IR, NMR spectra, mass spectrometry, elemental analysis, and X-ray crystallography. The X-ray crystallographic analysis of compounds 9a and 9b has revealed that the salt is formed with the nitrogen atom N3 when the aromatic substituents 9a and 9d are present, but in the case of compounds 9b, 9c, 9e, 9f, and 9g with the aliphatic substituent, the salt is formed outside the ring. Compounds 9a-g were evaluated for antiproliferative activity as multitargeted inhibitors. Results revealed that targets 9a-g displayed good antiproliferative activity, with GI50 ranging from 38 nM to 66 nM against a panel of four cancer cell lines compared to the reference Erlotinib (GI50 = 33 nM). Compounds 9a, 9c, and 9d were the most potent antiproliferative derivatives, with GI50 values of 43, 38, and 47 nM, respectively. Compounds 9a, 9c, and 9d were evaluated for their inhibitory activity against EGFR, BRAFV600E, and VEGFR-2. The in vitro experiments demonstrated that the compounds being examined exhibit potent antiproliferative properties and have the potential to function as multitargeted inhibitors. In addition, the western blotting investigation demonstrated the inhibitory effects of 9c on EGFR, BRAFV600E, and VEGFR-2.

Acetylenic Esters in Organic Synthesis

Activated acetylenic substrates such as acetylenic esters and alkyl propiolates are very important in organic synthesis. Due to their electron deficiency, these compounds are widely used in combinatorial and multicomponent reactions, enabling the synthesis of a large variety of novel compounds. In addition, these substrates are powerful Michael acceptors and convenient dienophiles and dipolarophiles in Diels–Alder and 1,3-dipolar cycloaddition reactions. The addition of different nucleophiles, primarily phosphorus, nitrogen or sulfur, to the triple bonds of these substrates produces key intermediates, such as Tebby and Huisgen zwitterions, which can lead to designing pathways toward the generation of spirocyclic and polycyclic compounds. This account highlights recent studies on the chemistry of acetylenic esters and their applications in organic synthesis.

1 Introduction

2 Synthesis of Acyclic and Monocyclic Compounds

3 Synthesis of Spirocyclic Compounds

4 Synthesis of Polycyclic Compounds

5 Conclusion