Tetraenone A: A New β-Ionone Derivative from Tetraena aegyptia

• Published in: Metabolites 2023-12, Vol.13 (12), p.1202
• Main Authors: Ashour, Ahmed, Sherif, Asmaa E, El-Sayed, Selwan M, Kim, Ji-Young, Jang, Dae Sik, Anvari, Abtin, Farahat, Abdelbasset A, Ibrahim, Sabrin R M, Mohamed, Gamal A, Ainousah, Bayan E, Aljohani, Raghad F, Al-Hejaili, Razan R, Khoja, Rahaf H, Hassan, Ahmed H E, Zaki, Ahmed A
• Format: Article
• Language: English
• Subjects: Acids; Carbon; Conformational analysis; Cotton; COVID-19; drug discovery; Ferulic acid; Ionone; life on land; megastigmene; p-Coumaric acid; Protein structure; SARS-CoV-2; Severe acute respiratory syndrome coronavirus 2; Tetraena; Tetraena aegyptia; tetraenone A; Viral infections
• ISSN: 2218-1989; 2218-1989
• DOI: 10.3390/metabo13121202

In this study, the chemical investigation of (Zygophyllaceae) led to the identification of a new megastigmene derivative, tetraenone A ((2 , 5 , 6 , 7 )-2-hydroxy-5,6-dihydro-β-ionone) ( ), along with (3 , 5 , 6 , 7 )-3-hydroxy-5,6-epoxy-5,6-dihydro-β-ionone- ( ), 3,4-dihydroxy-cinnamyl alcohol-4-glucoside ( ), 3β,19α-dihydroxy-ursan-28-oic acid ( ), quinovic acid ( ), -coumaric acid ( ), and ferulic acid ( ), for the first time. The chemical structures of - were confirmed by analysis of their 1D and 2D NMR and HRESIMS spectra and by their comparison with the relevant literature. The absolute configurations of and were assigned based on NOESY interactions and ECD spectra. Conformational analysis showed that existed exclusively in one of the two theoretically possible chair conformers with a predominant configuration for the 3-oxobut-1-en-1-yl group with the ring, while the half-chair conformer had a pseudo-axial hydroxy group that was predominant over the other half-chair conformation. Boat conformations were not among the most stable conformations, and the isomerism was in favor of configuration. In silico investigation revealed that and had more favorable binding interactions with M rather than with TMPRSS2. Accordingly, molecular dynamic simulations were performed on the complexes of compounds and with M to explore the stability of their interaction with the target protein structure. Compounds and might offer a possible starting point for developing covalent inhibitors of M of SARS-CoV-2.