New Phloroglucinol Derivatives from Hypericum papuanum

• Published in: Journal of natural products (Washington, D.C.) Vol. 63; no. 1; pp. 104 - 108
• Main Authors: Winkelmann, Karin, Heilmann, Jörg, Zerbe, Oliver, Rali, Topul, Sticher, Otto
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 01.01.2000; Amer Chemical Soc; American Society of Pharmacognosy
• Subjects: Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - isolation & purification; Anti-Bacterial Agents - pharmacology; antibacterial properties; antibiotics; Bacillus cereus; Bacteria - drug effects; Biological and medical sciences; chemical constituents of plants; chemical structure; Chemistry, Medicinal; General pharmacology; Hypericum; Hypericum - chemistry; Hypericum papuanum; leaves; Life Sciences & Biomedicine; Medical sciences; medicinal plants; Microbial Sensitivity Tests; Micrococcus luteus; Pharmacognosy. Homeopathy. Health food; Pharmacology & Pharmacy; Pharmacology. Drug treatments; phloroglucinol; Phloroglucinol - chemistry; Phloroglucinol - isolation & purification; Phloroglucinol - pharmacology; Plant Sciences; Plants, Medicinal; Science & Technology; spectral analysis; Spectrum Analysis; Staphylococcus epidermidis; Papua New Guinea; New Guinea; Melanesia; Oceania; Guttiferae; Enol; Bacillaceae; Medicinal plant; Bacillus cereus; Triketone; Bacillales; Folk medicine; Dicotyledones; Angiospermae; Bacteria; Micrococcales; Micrococcaceae; Pharmacognosy; Tautomer; Tricyclic compound; In vitro; Micrococcus luteus; Biological activity; Antibiotic; Staphylococcus epidermidis; Plant origin; Isolation; Above ground plant part; Spermatophyta; Antibacterial agent; Enone; Structural analysis
• ISSN: 0163-3864; 1520-6025
• DOI: 10.1021/np990417m

Bioactivity-guided fractionation of the petroleum ether extract of the aerial parts of Hypericum papuanum led to the isolation of five new tricyclic phloroglucinol derivatives. On the basis of extensive 1D and 2D NMR experiments as well as MS studies, their structures were elucidated as the C-3 epimers of 8-hydroxy-4,4,7-trimethyl-9-(2-methylpropionyl)-3-(1-methylvinyl)-5β-H-tricyclo[5.3.1.0 , ]undec-8-ene-10,11-dione (1, 2); the C-3 epimers of 8-hydroxy-4,4,7-trimethyl-9-(2-methylbutyryl)-3-(1-methylvinyl)-5β-H-tricyclo[5.3.1.01,5]undec-8-ene-10,11-dione (3, 4), and 8-hydroxy-4,4,7-trimethyl-9-(2-methylpropionyl)-5β-H-tricyclo[5.3.1.01,5]undec-8-ene-10,11-dione (5), and their corresponding tautomers (1a, 2a, 3a, 4a, 5a). Compounds 1/1a−5/5a were named ialibinones A−E, respectively. Compounds 1/1a−4/4a showed antibacterial activity against Bacillus cereus, Staphylococcus epidermidis, and Micrococcus luteus.