Design and chemical synthesis of fused 5-, 6oxygen and / or nitrogencontaining heterocyclesg lactam utilizing 2,3-dioxo-4carboxy-5-(substituted) pyrrolidine as the key precursor / Nurul Syafiqah Rezali

In this study, the development of synthetic strategy towards the formation of fused heterocyclic-y-lactam rings system containing oxygen and/ or nitrogen atom were successfully established. The key intermediate y-lactam or 2,3-pyrrolidinedione ring template was effectively constructed using a multicomponent reaction (MCR) approach utilizing primary amine, aldehyde and diethyl oxalacetate sodium salt in ethanolic medium. The y-lactam ring compound formed exists in the more stable enol form and also appears as racemic mixture. Following this, functional group interconversion of this highly functionalized compound leads to the formation of seven new fused heterocyclic-y-lactam rings system. The fused 5-lactam-y-lactam was effectively constructed via Leuckart reaction, condensation, hydrogenation and Dieckmann cyclisation. The synthesis of fused y-lactam-y-lactam however, involves decarboxylation, insertion of ethyl acetyl group via enamine-chemistry, imine formation and hydrogenation followed by an intramolecular cyclisation. The stereoselective reduction of the ethyl acetylic product followed by ester hydrolysis and lactonization via acid activation protocol was successfully carried out to furnish the fused y-lactone-y-lactam compound

Chemical constituents of the leaves of Actinodaphne pruinosa

ABSTRACT. This study was designed to investigate the chemical constituents from Actinodaphne pruinosa growing in Malaysia. A phytochemical investigation of the leaves part resulted in the isolation of boldine (1), norboldine (2), laurotetanine (3), reticuline (4), syringaresinol (5), lupeol (6), and taraxerol (7). The structures of the isolated phytochemicals were established by analysis of their spectroscopic data, as well as the comparison with that of reported data. Notably, this is the first time to report the isolation and structural elucidation of the constituents from the leaves part of A. pruinosa.   KEY WORDS: Actinodaphne pruinosa, Aporphine, Lauraceae, Phytochemical   Bull. Chem. Soc. Ethiop. 2022, 36(4), 963-969.                                                               DOI: https://dx.doi.org/10.4314/bcse.v36i4.2

Synthesis of Bio-Inspired 1,3-Diarylpropene Derivatives via Heck Cross-Coupling and Cytotoxic Evaluation on Breast Cancer Cells

International audienceThe Heck cross-coupling reaction is a well-established chemical tool for the synthesis of unsaturated compounds by formation of a new C-C bond. In this study, 1,3-diarylpropene derivatives, designed as structural analogues of stilbenoids and dihydrostilbenoids, were synthesised by the palladium-catalysed reactions of 2-amidoiodobenzene derivatives with either estragole or eugenol. The products were obtained with high (E) stereoselectivity but as two regioisomers. The ratios of isomers were found to be dependent on the nature of the allylbenzene partner and were rationalised by electronic effects exercising a determining influence in the β-hydride elimination step. In addition, the cytotoxic effects of all the Heck reaction products were evaluated against MCF-7 and MDA-MB-231 human breast cancer cells, with unpromising results. Among all, compound 7d exhibited weak cytotoxic activity towards MCF-7 cell lines with IC50 values of 47.92 µM in comparison with tamoxifen and was considered to have general toxicity (SI value < 2)