title: Four new sesquiterpenes from the rhizomes of Curcuma phaeocaulis and their iNOS inhibitory activities.
abstract: Three new guaiane-type sesquiterpenes named phaeocaulisins K-M (1-3), and one germacrane-type sesquiterpenoid with new ring system of 1,5- and 1,8-ether groups named phagermadiol (4), were isolated from rhizomes of Curcuma phaeocaulis. Their structures were established based on extensive spectroscopic analysis. Compound 1, the first example of norsesquiterpene with tropone backbone, and compound 3 with a novel 1,2-dioxolane sesquiterpene alcohol were isolated from the genus Curcuma. All of the isolated compounds were tested for inhibitory activity against lipopolysaccharide-induced nitric oxide (NO) production in RAW 264.7 macrophages. Compound 3 inhibited NO production with IC50 value of 6.05 ± 0.43 μM. The plausible biosynthetic pathway for compounds 3 and 4 in C. phaeocaulis was also discussed.
authors.affiliation: a Key Laboratory of Structure-Based Drug Design & Discovery, Department of Natural Products Chemistry , School of Traditional Chinese Materia Medica, Ministry of Education, Shenyang Pharmaceutical University , Shenyang 110016 , China.
authors.forename: Jiang-Hao
authors.initials: JH
authors.lastname: Ma
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Yue
authors.initials: Y
authors.lastname: Liu
authors.forename: Su-Yu
authors.initials: SY
authors.lastname: Gao
authors.forename: Li-Qin
authors.initials: LQ
authors.lastname: Ding
authors.forename: Feng
authors.initials: F
authors.lastname: Zhao
authors.forename: Li-Xia
authors.initials: LX
authors.lastname: Chen
authors.forename: Feng
authors.initials: F
authors.lastname: Qiu
mesh_terms: D000818:Animals; D030024:Curcuma / Q000737:chemistry*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects; D051379:Mice; D015394:Molecular Structure; D009569:Nitric Oxide / Q000096:biosynthesis; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors*; D019906:Nuclear Magnetic Resonance, Biomolecular; D027343:Rhizome / Q000737:chemistry*; D045789:Sesquiterpenes, Guaiane / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*
chemical_list: D008070:Lipopolysaccharides; D045789:Sesquiterpenes, Guaiane; D009569:Nitric Oxide; C496319:NOS2 protein, human; D052247:Nitric Oxide Synthase Type II
keywords: Curcuma phaeocaulis; germacrane; guaiane; nitric oxide; sesquiterpenes