Studies on the Constituents and Bioactivity of Clausena lansium from Vietnam and Semisynthesis of Clausenaline A

  • 沈 德鍚

Student thesis: Doctoral Thesis

Abstract

Clausena lansium Skeels (Rutaceae) also known as “wampee” originates from southern mainland China Several parts of C lansium have been used in folk medicine in the People’s Republic of China Taiwan and Philippines Eight new carbazole alkaloids 1′-O-methylclaulamine B 1′-acetylclaulamine B and claulamine E and clausenalines B–F four new coumarins clausemarins A–D and 43 known compounds were isolated from the roots of Clausena lansium Two new glycosides clausenosides A and B and three new carbazole alkaloids clausenaline A claulamines A and B together with 50 known compounds were isolated from the stems of Clausena lansium Thirteen new amides 6′-O-methylneoclausenamide 6′-O-methyl-epi-neoclausenamide 6′-O-methyl-epi-cis-neoclausenamide lansamides 5–9 clausenalansamide C–G were characterized from the leaves of Clausena lansium In this work the methanolic extracts of root stem and leaf from C lansium were collected in Vietnam Carbazole alkaloids and coumarins were identified as the major components in the root and stem The composition of the methanolic extract obtained from the leaves was quite different The major component was cyclic amides; the other major components were acyclic amides Previously δ-lactam and γ-lactam isolated from the leaves were all racemates In this work we found the amides that including δ-lactam γ-lactam and acyclic amides were all optical active Since this plant was provided by Vietnam different origin than mainland China may cause differences in composition The results found that the compounds of carbazole type if there is a carbonyl group at C-3 position for example the compounds of 6 11 12 13 43 60 and 342 have significant anti-inflammatory activity Furthermore coumarin compounds which have double bond at the 2' 3' position such as compounds 137 140 201 334 335 and 359 also have significant anti-inflammatory effect The compound 96 had moderate inhibition against KBVIN cell line compared to compound 81 and 98 Compounds 388 and 417 exhibited statistically significant neuroprotective effects against Aβ25?35-induced neonatal cortical neurons death compared with the Aβ25?35-treated group A plausible biosynthetic pathway for the production of 76 81 96 and 98 from 87 was proposed To confirm the structure of clausenaline A (76) a partial synthesis from co-isolated 87 was performed
Date of Award2015 Feb 13
Original languageEnglish
SupervisorTian-Shung Wu (Supervisor)

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