Microwave Assisted Synthesis of 4-Phenylquinazolin-2(1H)-one Derivatives that Inhibit Vasopressor Tonus in Rat Thoracic Aorta

Design, synthesis, and in silico studies of new quinazolinones tagged thiophene, thienopyrimidine, and thienopyridine scaffolds as antiproliferative agents with potential p38α MAPK kinase inhibitory effects

The current work focuses on the creation of novel derivatives of the quinazolinone ring system, with various substituted thiophene, thienopyrimidine, and thienopyridine scaffolds 3a,b-11. Employing the standard MTT assay, every target compound's in vitro antiproliferative efficacy was evaluated in comparison with doxorubicin against both normal WI-38 cells and various cancer cell lines. Derivatives 6, 8a, and 8b demonstrated the most potent activity, alongside their safety profiles against WI-38. The in vitro enzyme assay showed that the new analogues had a better ability to inhibit p38α MAPK kinase than SB 202190 (IC50s = 0.18 ± 0.02, 0.23 ± 0.05, 0.31 ± 0.04, and 0.27 ± 0.06 μM, respectively). Additionally, apoptosis tests conducted on MCF-7 cells revealed that 6, 8a, and 8b significantly increased the levels of Bax (by approximately 7.31, 13.8, and 8.86 fold) and caspase 3 (by approximately 3.55, 4.22, and 3.87 fold), respectively, in comparison to the untreated cells. They decreased the amount of Bcl-2 by ∼1.99, 3.69, and 2.66 fold, respectively. The most powerful counterpart, 8a, underwent additional investigation of the cell cycle and apoptosis. It caused necrotic and apoptotic effects in the late stages and stopped the MCF-7 cell cycle at the G2/M phase. Based on the molecular docking study, candidates 6, 8a, and 8b all fit well within p38α MAPK kinase, with energy scores of -10.88, -11.28, and -10.96 kcal mol-1, respectively. Based on the in silico computer examination of physico-chemical and ADMET properties, the latter analogues seem to be promising candidates for further development and optimization in research.

Piper tectoniifolium Kunth: A New Natural Source of the Bioactive Neolignan (-)-Grandisin

The Piper species are a recognized botanical source of a broad structural diversity of lignans and its derivatives. For the first time, Piper tectoniifolium Kunth is presented as a promising natural source of the bioactive (−)-grandisin. Phytochemical analyses of extracts from its leaves, branches and inflorescences showed the presence of the target compound in large amounts, with leaf extracts found to contain up to 52.78% in its composition. A new HPLC-DAD-UV method was developed and validated to be selective for the identification of (−)-grandisin being sensitive, linear, precise, exact, robust and with a recovery above 90%. The absolute configuration of the molecule was determined by X-ray diffraction. Despite the identification of several enantiomers in plant extracts, the major isolated substance was characterized to be the (−)-grandisin enantiomer. In vascular reactivity tests, it was shown that the grandisin purified from botanical extracts presented an endothelium-dependent vasorelaxant effect with an IC₅₀ of 9.8 ± 1.22 μM and around 80% relaxation at 30 μM. These results suggest that P. tectoniifolium has the potential to serve as a renewable source of grandisin on a large scale and the potential to serve as template for development of new drugs for vascular diseases with emphasis on disorders related to endothelial disfunction.