Dihydro-furanones from Hyptis species: Chemical correlations and DFT-NMR/ECD calculations for stereochemical assignments

• Published in: Phytochemistry (Oxford) Vol. 179; p. 112481
• Main Authors: Martínez-Fructuoso, Lucero, Pereda-Miranda, Rogelio, Fragoso-Serrano, Mabel, da Silva, Aline Soares, Leitão, Suzana Guimarães
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 01.11.2020; Elsevier
• Subjects: Biochemistry & Molecular Biology; Butenolide; Hyptis monticola; Hyptis pectinata; Lamiaceae; Life Sciences & Biomedicine; Plant Sciences; Quantum mechanics calculations; Science & Technology; δ-Lactone; Lamiaceae; Hyptis monticola; Butenolide; Hyptis pectinata; Quantum mechanics calculations; δ-Lactone; BREVIPOLIDES; 5,6-DIHYDRO-ALPHA-PYRONES; BUTENOLIDE DERIVATIVES; delta-Lactone; CONFORMATIONAL-ANALYSIS; MARINE; COUPLING-CONSTANTS
• ISSN: 0031-9422; 1873-3700
• DOI: 10.1016/j.phytochem.2020.112481

Dihydro-furanones are bioactive compounds isolated from various plants, marine fungi, and sponges. The present investigation describes the isolation by recycling HPLC and structural characterization by NMR of four previously undescribed 2(5H)-furanones, monticofuranolide A and pectinolides N–P, one phenylpropanoid, rosmarinic acid, and five known flavonoids, in addition to the undescribed natural flavonoid, 2R,3R-dihydrogossipetin or 5,7,8,3′,4′-pentahydroxy flavanonol, from collections of H. monticola Mart. ex Benth and Hyptis pectinata (L.) Poit. Chemical correlations, resembling the biogenetic relationship of the isolated 2(5H)-furanones with their 5,6-dihydro-2H-pyran-2-one precursors, were accomplished to confirm their absolute configuration. Density functional theory-NMR/ECD calculations have been used to solve the absolute configuration for this type of compounds. The absolute configuration of 2(5H)-furanones from Hyptis was secured by chemical correlations with the dihydro-2H-pyran-2-one precursors and DFT-NMR/ECD calculations. [Display omitted] •Four undescribed dihydro-furanones were isolated from two Hyptis species.•Correlations with the dihydro-pyranone precursors secured their absolute configurations.•2R,3R-Dihydrogossipetin was isolated as a natural flavonoid.•2(5H)-Furanones were slightly cytotoxic.