A New Coumarin and Carbazole Alkaloid from Clausena vestita D. D. Tao

Abstract

Phytochemical investigation of the EtOH extract of Clausena vestita D. D. Tao led to the isolation of one new coumarin, clauslactone U (1), and one new carbazole alkaloid, clauszoline N (2), together with 28 known compounds. The structures of these compounds were established by using MS and 1D‐ and 2D‐NMR techniques, and by comparison with known analogues.

Synthesis and Structure–Activity Relationships of Lansine Analogues as Antileishmanial Agents

“…All compounds are nontoxic to VERO cells at 20 μg/mL (CC 50 >20 μg/mL). In addition, a previous report has indicated that lansine ( 6a ) and 5g are associated with CC values of >102 μg/mL in VERO cells, [15] which further support the favorable safety profile of this series of derivatives.…”

“…[15] To a stirred solution of 6a (70 mg, 0.29 mmol) in dry DCM (2 mL), BBr 3 (0.14 mL, 1.45 mmol) was added at 0°C, and the dark red solution was stirred for 30 minutes. The mixture was then washed with water.…”

“…Methylation of lansine ( 6a) with MeI using NaH as a base, resulted in the formation of compounds 8 [14] and 9 , while O -demethylation of lansine ( 6a ) with BBr 3 led to the first synthesis of the known natural product 7 . [15] …”

Palladium(II)‐Catalyzed Synthesis of the Formylcarbazole Alkaloids Murrayaline A–C, 7‐Methoxymukonal, and 7‐Methoxy‐O‐methylmukonal

“…F by Ito et al,3 from Clausena vestita D. D. Tao by Zhao et al,4 and from Clausena wallichii by Laphookhieo et al5 In 1990, Lange et al reported the first isolation of the corresponding methyl ether, 7‐methoxy‐ O ‐methylmukonal ( 2 ), from the roots of Murraya siamensis , which was collected in Thailand 6. Subsequently, compound 2 was also isolated from Clausena excavata by Wu et al,7 from Clausena vestita D. D. Tao by Zhao et al,4 and from the roots of Clausena wallichii by Laphookhieo and co‐workers 5. A variety of biological activities has been reported for 7‐methoxymukonal ( 1 ) and 7‐methoxy‐ O ‐methylmukonal ( 2 ).…”

Antibacterial carbazole alkaloids from Clausena harmandiana twigs

“…Many of carbazole alkaloids as well as coumarins were recognized as major compounds of C. harmandiana and some of them displayed interesting biological activities including antimalaria, anti-TB, cytotoxicity, and stimulate glucose uptake in L6 myotubes [1][2][3][4]. In a continuing search for bioactive metabolites from Clausena plants [5][6][7][8][9], we report herein the isolation and identification of three new carbazole alkaloids (1)(2)(3), harmandianamines A-C, along with fifteen known compounds including clausevatine D (4) [11], clausamine A (5) [12], clausamine B (6) [12], clausine S (7) [13], girinimbine (8) [14], O-demethylmurrayanine (9) [15], clauszoline I (10) [16], clausine Z (11) [17], clauszoline N (12) [18], clausine D (13) [19], clausine F (14) [19], clausemine D (15) [20], heptaphylline (16) [21], dectamine (17) [22], and γ-fagarine (18) [22] (Fig. 1) from C. harmandiana twigs.…”