RESUMEN
Metal-catalysed cross-coupling reactions are amongst the most widely used methods to directly construct new bonds. In this connection, sustainable and practical protocols, especially transition metal-catalysed cross-coupling reactions, have become the focus in many aspects of synthetic chemistry due to their high efficiency and atom economy. This review summarises recent advances from 2012 to 2022 in the formation of carbon-carbon bonds and carbon-heteroatom bonds by employing organo-alkali metal reagents.
RESUMEN
Three new prenylated stilbenes, named as cajanusins A-C (1-3), and one new natural product cajanusin D (4), along with six known derivatives (5-10) were isolated from the leaves of Cajanus cajan. Their structures were fully elucidated by means of extensive spectroscopic methods and comparison with data in the reported literatures. The new compounds of 1 and 2 were evaluated for in vitro cytotoxic activities against a panel of human cancer cell lines.
Asunto(s)
Antineoplásicos Fitogénicos/química , Cajanus/química , Flavonoides/química , Estilbenos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/toxicidad , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Flavonoides/aislamiento & purificación , Humanos , Estructura Molecular , Extractos Vegetales/química , Hojas de la Planta/química , Estilbenos/aislamiento & purificación , Estilbenos/toxicidadRESUMEN
A pair of epimer brachyanins A (1) and B (2), along with a new phloroglucinol brachyanin C (3), were isolated from the leaves of Leptospermum brachyandrum. Brachyanins A (1) and B (2) were the first example of novel meroterpenoid with a unique skeleton that combined a synacrpic acid and a pinene units via a benzyl moiety. Their structures were elucidated through the application of extensive spectroscopic measurements and single-crystal X-ray diffraction analysis and with the absolute configurations of 1 and 2 were confirmed by the quantum chemical CD calculation. The hetero Diels-Alder as the key biotransformation was proposed to account for the biosynthesis of brachyanins A and B sheding light by the potential procursor brachyanin C.